From 3917d50590bbc2328d97e925d48d56c4b1af5104 Mon Sep 17 00:00:00 2001
From: Andreas Fertig <andy@cppinsights.io>
Date: Thu, 8 Feb 2024 14:18:28 +0100
Subject: [PATCH]  Code for 2nd edition

---
 .github/workflows/ci.yml                      | 48 +++++-----
 01.01-variadicTemplateSum2/CMakeLists.txt     |  2 +-
 01.02-variableTemplate0/CMakeLists.txt        |  2 +-
 01.05-variadicTemplateSum3/CMakeLists.txt     |  2 +-
 01.06-simpleRequirement0/CMakeLists.txt       |  2 +-
 01.06-simpleRequirement0/main.cpp             |  9 +-
 01.07-nestedRequirement0/CMakeLists.txt       |  2 +-
 01.08-compoundRequirement0/CMakeLists.txt     |  2 +-
 01.08-compoundRequirement0/main.cpp           |  2 +-
 01.09-typeRequirement0/CMakeLists.txt         |  2 +-
 01.09-typeRequirement0/main.cpp               |  3 +-
 01.10-compoundRequirement1/CMakeLists.txt     |  2 +-
 01.10-compoundRequirement1/main.cpp           |  2 +-
 01.11-compoundRequirement2/CMakeLists.txt     |  2 +-
 01.11-compoundRequirement2/main.cpp           |  2 +-
 01.12-testingRequirements0/CMakeLists.txt     |  2 +-
 01.12-testingRequirements0/main.cpp           | 16 ++--
 01.14-invocable0/CMakeLists.txt               |  2 +-
 01.14-invocable0/main.cpp                     |  2 +-
 01.15-invocable1/CMakeLists.txt               |  2 +-
 01.15-invocable1/main.cpp                     |  2 +-
 .../CMakeLists.txt                            |  2 +-
 01.18-vectorsSize0/CMakeLists.txt             |  2 +-
 01.21-vectorsSize1/CMakeLists.txt             |  2 +-
 .../CMakeLists.txt                            |  2 +-
 01.22-validateInDebugModeIfExists0/main.cpp   |  5 +-
 01.24-optional0/CMakeLists.txt                |  2 +-
 01.26-optional1/CMakeLists.txt                |  2 +-
 01.27-optional2/CMakeLists.txt                |  2 +-
 01.27-optional2/main.cpp                      |  8 +-
 01.28-optional3/CMakeLists.txt                |  2 +-
 01.28-optional3/main.cpp                      | 11 +--
 01.29-optional4/CMakeLists.txt                |  2 +-
 01.29-optional4/main.cpp                      | 18 ++--
 01.32-optional5/CMakeLists.txt                |  2 +-
 01.32-optional5/main.cpp                      | 33 +++----
 01.33-optional6/CMakeLists.txt                |  2 +-
 01.33-optional6/main.cpp                      | 37 ++++----
 01.34-isSameConcept0/CMakeLists.txt           |  2 +-
 01.34-isSameConcept0/main.cpp                 |  4 +-
 01.36-isSameConcept1/CMakeLists.txt           |  2 +-
 01.36-isSameConcept1/main.cpp                 |  4 +-
 01.37-isSameConcept2/CMakeLists.txt           |  2 +-
 01.37-isSameConcept2/main.cpp                 |  4 +-
 01.38-isSameConcept3/CMakeLists.txt           |  2 +-
 01.38-isSameConcept3/main.cpp                 |  8 +-
 01.40-printSorted0/CMakeLists.txt             |  2 +-
 01.42-printSorted1/CMakeLists.txt             |  2 +-
 01.42-printSorted1/main.cpp                   | 10 +--
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 02.08-parsingDataStream0/CMakeLists.txt       |  2 +-
 02.08-parsingDataStream0/main.cpp             |  2 +-
 .../CMakeLists.txt                            |  2 +-
 02.10-coroutineParsingDataStream0/main.cpp    |  1 +
 .../CMakeLists.txt                            |  2 +-
 02.18-coroutineParsingDataStream1/main.cpp    |  1 +
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  |  1 +
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  |  1 +
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  |  9 +-
 03.01-rangesMotivation0/CMakeLists.txt        |  2 +-
 03.02-rangesMotivation1/CMakeLists.txt        |  2 +-
 03.03-rangesMotivation2/CMakeLists.txt        |  2 +-
 03.03-rangesMotivation2/main.cpp              | 16 +---
 03.04-twoStepUsing0/CMakeLists.txt            |  2 +-
 03.04-twoStepUsing0/main.cpp                  |  4 +-
 03.05-twoStepUsing1/CMakeLists.txt            |  5 +-
 03.06-twoStepUsing2/CMakeLists.txt            |  5 +-
 03.07-rangesSafety0/CMakeLists.txt            |  2 +-
 03.08-rangesSafety1/CMakeLists.txt            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 03.09-rangesMotivationComposability0/main.cpp |  4 +-
 .../CMakeLists.txt                            |  2 +-
 03.10-rangesMotivationComposability1/main.cpp | 17 ++--
 03.11-aRange0/CMakeLists.txt                  |  2 +-
 03.13-rangesCommonView1/CMakeLists.txt        |  2 +-
 03.14-rangesCommonView2/CMakeLists.txt        |  2 +-
 03.14-rangesCommonView2/main.cpp              | 17 ++--
 03.15-rangesProjection0/CMakeLists.txt        |  2 +-
 03.17-rangesProjection1/CMakeLists.txt        |  2 +-
 03.17-rangesProjection1/main.cpp              | 22 ++---
 .../CMakeLists.txt                            |  2 +-
 03.18-rangesMotivationComposability2/main.cpp | 19 ++--
 03.19-rangesCustomAdaptor0/CMakeLists.txt     |  2 +-
 03.19-rangesCustomAdaptor0/main.cpp           | 22 ++---
 03.20-rangesCustomAdaptor1/CMakeLists.txt     |  2 +-
 03.20-rangesCustomAdaptor1/main.cpp           | 22 ++---
 03.22-rangesNamespaces0/CMakeLists.txt        |  2 +-
 03.22-rangesNamespaces0/main.cpp              |  8 +-
 03.23-rangesCustomTakeView0/CMakeLists.txt    |  2 +-
 03.23-rangesCustomTakeView0/main.cpp          | 32 +++----
 03.29-rangesCustomTakeView1/CMakeLists.txt    |  2 +-
 03.29-rangesCustomTakeView1/main.cpp          | 26 ++----
 04.01-includeHell0/CMakeLists.txt             |  2 +-
 04.03-moduleSkeleton0/CMakeLists.txt          |  2 +-
 04.04-namespaceDetails0/CMakeLists.txt        |  2 +-
 04.05-namespaceDetails1/CMakeLists.txt        |  2 +-
 04.06-downWithDebug0/CMakeLists.txt           |  2 +-
 04.10-downWithDebug1/CMakeLists.txt           |  2 +-
 04.11-inClassMemberFunction0/CMakeLists.txt   |  2 +-
 04.12-assertImpl0/CMakeLists.txt              |  2 +-
 05.01-stdFmtStockIndex0/CMakeLists.txt        |  2 +-
 05.01-stdFmtStockIndex0/main.cpp              | 24 ++---
 05.03-digitSeparator0/CMakeLists.txt          |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 05.10-stdFmtEscape0/CMakeLists.txt            |  2 +-
 05.10-stdFmtEscape0/main.cpp                  | 13 +--
 05.11-stdFmtLocale0/CMakeLists.txt            |  2 +-
 05.11-stdFmtLocale0/main.cpp                  | 20 ++---
 05.12-stdFmtFloatFormatting0/CMakeLists.txt   |  2 +-
 05.12-stdFmtFloatFormatting0/main.cpp         | 18 +---
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  | 29 ++----
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  | 28 +++---
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  | 28 +++---
 05.19-stdFmtFormattingShares0/CMakeLists.txt  |  2 +-
 05.19-stdFmtFormattingShares0/main.cpp        | 22 ++---
 05.21-stdFmtFormatTo0/CMakeLists.txt          |  2 +-
 05.21-stdFmtFormatTo0/main.cpp                | 20 ++---
 05.22-stdFmtFormatTo1/CMakeLists.txt          |  2 +-
 05.22-stdFmtFormatTo1/main.cpp                | 20 ++---
 05.23-stdFmtFormatTo2/CMakeLists.txt          |  2 +-
 05.23-stdFmtFormatTo2/main.cpp                | 20 ++---
 05.24-stdFmtFormatToN0/CMakeLists.txt         |  2 +-
 05.24-stdFmtFormatToN0/main.cpp               | 18 ++--
 05.25-stdFmtCustomLogger0/CMakeLists.txt      |  2 +-
 05.25-stdFmtCustomLogger0/main.cpp            | 42 ++++-----
 05.27-stdFmtCustomLogger1/CMakeLists.txt      |  2 +-
 05.27-stdFmtCustomLogger1/main.cpp            | 26 ++++--
 05.29-stdFmtCustomLogger2/CMakeLists.txt      |  2 +-
 05.29-stdFmtCustomLogger2/main.cpp            | 45 +++++-----
 05.32-stdFmtCustomLogger4/CMakeLists.txt      |  2 +-
 05.32-stdFmtCustomLogger4/main.cpp            | 60 +++++++------
 06.01-equalComparOfMRN0/CMakeLists.txt        |  2 +-
 06.02-equalComparOfMRN1/CMakeLists.txt        |  2 +-
 06.04-equalComparOfMRN2/CMakeLists.txt        |  2 +-
 06.05-equalComparOfMRN3/CMakeLists.txt        |  2 +-
 .../CMakeLists.txt                            |  2 +-
 06.06-orderingComparisonString0/main.cpp      | 10 +--
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 06.08-orderingComparisonString2/main.cpp      |  2 +-
 .../CMakeLists.txt                            |  2 +-
 06.09-orderingComparisonString4/main.cpp      | 64 +++++++++++++
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  |  0
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  |  0
 {06.12-bcd1 => 06.12-bcd0}/CMakeLists.txt     |  2 +-
 {06.11-bcd0 => 06.12-bcd0}/main.cpp           |  0
 06.13-bcd1/CMakeLists.txt                     | 90 +++++++++++++++++++
 {06.12-bcd1 => 06.13-bcd1}/main.cpp           |  0
 06.13-bcdConstexpr/CMakeLists.txt             | 90 -------------------
 06.14-bcdConstexpr/CMakeLists.txt             | 90 +++++++++++++++++++
 .../main.cpp                                  |  0
 06.14-customOrdering0/CMakeLists.txt          | 90 -------------------
 06.15-customOrdering0/CMakeLists.txt          | 90 +++++++++++++++++++
 .../main.cpp                                  | 13 +--
 06.15-customOrdering1/CMakeLists.txt          | 90 -------------------
 06.16-customOrdering1/CMakeLists.txt          | 90 +++++++++++++++++++
 .../main.cpp                                  | 14 +--
 06.16-spaceshipWithLegacyCode0/CMakeLists.txt | 90 -------------------
 06.17-spaceshipWithLegacyCode0/CMakeLists.txt | 90 +++++++++++++++++++
 .../main.cpp                                  |  0
 ...> 06.18-see-06.17-spaceshipWithLegacyCode0 |  0
 .../CMakeLists.txt                            | 90 -------------------
 .../CMakeLists.txt                            | 90 +++++++++++++++++++
 .../main.cpp                                  |  0
 07.01-captureByCopy0/CMakeLists.txt           |  2 +-
 07.02-captureByCopy1/CMakeLists.txt           |  2 +-
 07.03-captureByCopy1Insights/CMakeLists.txt   |  2 +-
 07.04-captureByCopy2/CMakeLists.txt           |  2 +-
 07.05-mapSortBooksByIsbn0/CMakeLists.txt      |  2 +-
 07.07-mapSortBooksByIsbn1/CMakeLists.txt      |  2 +-
 07.08-mapSortBooksByIsbn2/CMakeLists.txt      |  2 +-
 07.09-mapSortBooksByIsbn3/CMakeLists.txt      |  2 +-
 07.09-mapSortBooksByIsbn3/main.cpp            | 11 ++-
 07.13-mapSortBooksByIsbn4/CMakeLists.txt      |  2 +-
 07.14-printWithOrigin0/CMakeLists.txt         |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 07.19-lambdaInitCapture0/CMakeLists.txt       |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 07.25-genericLambdaVarArgsForward7/main.cpp   |  4 +-
 08.01-aggregateInit0/CMakeLists.txt           |  2 +-
 08.02-userProvidedVsDeclared0/CMakeLists.txt  |  2 +-
 08.03-designatedInitializers0/CMakeLists.txt  |  2 +-
 08.04-designatedInitializers1/CMakeLists.txt  |  2 +-
 08.05-mostVertexingParse0/CMakeLists.txt      |  2 +-
 08.06-designatedInitializers2/CMakeLists.txt  |  2 +-
 08.07-designatedInitializers3/CMakeLists.txt  |  2 +-
 08.09-designatedInitializers4/CMakeLists.txt  |  2 +-
 08.10-guaranteedCopyElision0/CMakeLists.txt   |  2 +-
 08.11-designatedInitializers5/CMakeLists.txt  |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  |  4 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 08.21-initializationForms0/CMakeLists.txt     |  2 +-
 08.21-initializationForms0/main.cpp           |  4 +-
 .../CMakeLists.txt                            |  2 +-
 08.25-ctad0/CMakeLists.txt                    |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 09.01-stdArray0/CMakeLists.txt                |  2 +-
 09.02-floatingPointNTTP0/CMakeLists.txt       |  2 +-
 09.03-fixedString0/CMakeLists.txt             |  2 +-
 09.04-fixedString1/CMakeLists.txt             |  2 +-
 09.04-fixedString1/main.cpp                   |  9 +-
 09.12-fixedString2/CMakeLists.txt             |  2 +-
 09.12-fixedString2/main.cpp                   |  9 +-
 09.13-fixedString3/CMakeLists.txt             |  2 +-
 09.13-fixedString3/main.cpp                   | 19 +---
 10.01-bitCastFloatToInt0/CMakeLists.txt       |  2 +-
 10.02-bitCastFloatToInt1/CMakeLists.txt       |  2 +-
 10.03-byteSwap0/CMakeLists.txt                |  2 +-
 10.03-byteSwap0/main.cpp                      |  6 +-
 10.04-stdArrayVsCArray0/CMakeLists.txt        |  2 +-
 10.05-stdArrayVsCArray1/CMakeLists.txt        |  2 +-
 10.06-stdArrayVsCArray2/CMakeLists.txt        |  2 +-
 10.07-lengthAndValue0/CMakeLists.txt          |  2 +-
 10.08-lengthAndValue1/CMakeLists.txt          |  2 +-
 10.09-lengthAndValue2/CMakeLists.txt          |  2 +-
 10.10-span0/CMakeLists.txt                    |  2 +-
 10.11-assert0/CMakeLists.txt                  |  2 +-
 10.13-assert1/CMakeLists.txt                  |  2 +-
 10.13-assert1/main.cpp                        | 15 +---
 10.14-logFunction0/CMakeLists.txt             |  2 +-
 10.14-logFunction0/main.cpp                   | 22 ++---
 10.15-logFunction1/CMakeLists.txt             |  2 +-
 10.15-logFunction1/main.cpp                   | 27 ++----
 10.16-logFunction2/CMakeLists.txt             |  2 +-
 10.16-logFunction2/main.cpp                   | 21 ++---
 10.17-mapContains0/CMakeLists.txt             |  2 +-
 10.18-mapContains1/CMakeLists.txt             |  2 +-
 10.19-startsWith0/CMakeLists.txt              |  2 +-
 10.19-startsWith0/main.cpp                    |  2 +-
 10.20-startsWith1/CMakeLists.txt              |  2 +-
 10.20-startsWith1/main.cpp                    |  4 +-
 11.01-rangeBaseForWithInit0/CMakeLists.txt    |  2 +-
 11.02-rangeBaseForWithInit1/CMakeLists.txt    |  2 +-
 11.03-rangeBaseForWithInit2/CMakeLists.txt    |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../main.cpp                                  | 13 ++-
 .../CMakeLists.txt                            |  2 +-
 11.06-likely0/CMakeLists.txt                  |  2 +-
 11.06-likely0/main.cpp                        |  6 +-
 11.07-likely1/CMakeLists.txt                  |  2 +-
 11.07-likely1/main.cpp                        |  6 +-
 11.08-notCopyable0/CMakeLists.txt             |  2 +-
 11.09-notCopyable1/CMakeLists.txt             |  2 +-
 11.10-usingEnum0/CMakeLists.txt               |  2 +-
 11.11-usingEnum1/CMakeLists.txt               |  2 +-
 11.12-conditionalExplicit0/CMakeLists.txt     |  2 +-
 11.13-conditionalExplicit1/CMakeLists.txt     |  2 +-
 11.14-conditionalExplicit2/CMakeLists.txt     |  2 +-
 11.15-conditionalExplicit5/CMakeLists.txt     |  2 +-
 12.01-constexprStrlenCpp110/CMakeLists.txt    |  2 +-
 12.02-constexprStrlenCpp111/CMakeLists.txt    |  2 +-
 12.03-constexprPoint0/CMakeLists.txt          |  2 +-
 12.04-constexprThrow0/CMakeLists.txt          |  2 +-
 12.05-throwAtCompileTime0/CMakeLists.txt      |  2 +-
 12.06-logStatementInConstexpr0/CMakeLists.txt |  2 +-
 12.08-byteSwap1/CMakeLists.txt                |  2 +-
 12.08-byteSwap1/main.cpp                      | 13 ++-
 .../CMakeLists.txt                            |  5 +-
 12.10-constexprAllocation0/CMakeLists.txt     |  2 +-
 12.12-constexprAllocation1/CMakeLists.txt     |  2 +-
 12.14-constexprAllocation2/CMakeLists.txt     |  4 +-
 12.14-constexprAllocation2/main.cpp           | 22 ++---
 12.15-asConstant0/CMakeLists.txt              |  5 +-
 12.16-asConstant1/CMakeLists.txt              |  5 +-
 12.16-asConstant1/main.cpp                    |  2 +-
 12.18-constevalParmCheck0/CMakeLists.txt      |  2 +-
 12.19-constevalParmCheck1/CMakeLists.txt      |  2 +-
 12.19-constevalParmCheck1/main.cpp            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 .../CMakeLists.txt                            |  2 +-
 CMakeLists.txt                                |  2 +-
 LICENSE.txt                                   |  2 +-
 Readme.md                                     | 12 +--
 302 files changed, 1251 insertions(+), 1381 deletions(-)
 rename {06.09-orderingComparisonString3 => 06.09-orderingComparisonString4}/CMakeLists.txt (97%)
 create mode 100644 06.09-orderingComparisonString4/main.cpp
 rename {06.10-spaceshipResultingType0 => 06.10-orderingComparisonString3}/CMakeLists.txt (97%)
 rename {06.09-orderingComparisonString3 => 06.10-orderingComparisonString3}/main.cpp (100%)
 rename {06.11-bcd0 => 06.11-spaceshipResultingType0}/CMakeLists.txt (97%)
 rename {06.10-spaceshipResultingType0 => 06.11-spaceshipResultingType0}/main.cpp (100%)
 rename {06.12-bcd1 => 06.12-bcd0}/CMakeLists.txt (97%)
 rename {06.11-bcd0 => 06.12-bcd0}/main.cpp (100%)
 create mode 100644 06.13-bcd1/CMakeLists.txt
 rename {06.12-bcd1 => 06.13-bcd1}/main.cpp (100%)
 delete mode 100644 06.13-bcdConstexpr/CMakeLists.txt
 create mode 100644 06.14-bcdConstexpr/CMakeLists.txt
 rename {06.13-bcdConstexpr => 06.14-bcdConstexpr}/main.cpp (100%)
 delete mode 100644 06.14-customOrdering0/CMakeLists.txt
 create mode 100644 06.15-customOrdering0/CMakeLists.txt
 rename {06.14-customOrdering0 => 06.15-customOrdering0}/main.cpp (80%)
 delete mode 100644 06.15-customOrdering1/CMakeLists.txt
 create mode 100644 06.16-customOrdering1/CMakeLists.txt
 rename {06.15-customOrdering1 => 06.16-customOrdering1}/main.cpp (88%)
 delete mode 100644 06.16-spaceshipWithLegacyCode0/CMakeLists.txt
 create mode 100644 06.17-spaceshipWithLegacyCode0/CMakeLists.txt
 rename {06.16-spaceshipWithLegacyCode0 => 06.17-spaceshipWithLegacyCode0}/main.cpp (100%)
 rename 06.17-see-06.16-spaceshipWithLegacyCode0 => 06.18-see-06.17-spaceshipWithLegacyCode0 (100%)
 delete mode 100644 06.18-spaceshipEqualityRewrite2/CMakeLists.txt
 create mode 100644 06.19-spaceshipEqualityRewrite2/CMakeLists.txt
 rename {06.18-spaceshipEqualityRewrite2 => 06.19-spaceshipEqualityRewrite2}/main.cpp (100%)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 747b0a1..b696cf0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -4,7 +4,7 @@ name: ci
 on: [push, pull_request]
 
 env:
-  CMAKE_VERSION: 3.16.2
+  CMAKE_VERSION: 3.28.2
   NINJA_VERSION: 1.10.0
 
 jobs:
@@ -15,22 +15,22 @@ jobs:
       fail-fast: false
       matrix:
         config:
-        # GCC-10
+        # GCC-13
         - {
-            name: "Linux GCC 11",
-            os: ubuntu-20.04,
+            name: "Linux GCC 13",
+            os: ubuntu-22.04,
             build_type: Release,
-            cxx: "g++-11",
-            gcc_version: 11,
+            cxx: "g++-13",
+            gcc_version: 13,
           }
 
-        # Clang-14
+        # Clang-17
         - {
-            name: "Linux Clang 14",
-            os: ubuntu-20.04,
+            name: "Linux Clang 17",
+            os: ubuntu-22.04,
             build_type: Release,
-            cxx: "clang++-14",
-            clang_version: 14,
+            cxx: "clang++-17",
+            clang_version: 17,
             libcxx: true
           }
 
@@ -52,7 +52,7 @@ jobs:
           }
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
       with:
         fetch-depth: 2
 
@@ -67,16 +67,16 @@ jobs:
 
         if ("${{ runner.os }}" STREQUAL "Windows")
           set(ninja_suffix "win.zip")
-          set(cmake_suffix "win64-x64.zip")
-          set(cmake_dir "cmake-${cmake_version}-win64-x64/bin")
+          set(cmake_suffix "windows-x86_64.zip")
+          set(cmake_dir "cmake-${cmake_version}-windows-x86_64/bin")
         elseif ("${{ runner.os }}" STREQUAL "Linux")
           set(ninja_suffix "linux.zip")
-          set(cmake_suffix "Linux-x86_64.tar.gz")
-          set(cmake_dir "cmake-${cmake_version}-Linux-x86_64/bin")
+          set(cmake_suffix "linux-x86_64.tar.gz")
+          set(cmake_dir "cmake-${cmake_version}-linux-x86_64/bin")
         elseif ("${{ runner.os }}" STREQUAL "macOS")
           set(ninja_suffix "mac.zip")
-          set(cmake_suffix "Darwin-x86_64.tar.gz")
-          set(cmake_dir "cmake-${cmake_version}-Darwin-x86_64/CMake.app/Contents/bin")
+          set(cmake_suffix "macos-universal.tar.gz")
+          set(cmake_dir "cmake-${cmake_version}-macos-universal/CMake.app/Contents/bin")
         endif()
 
         set(ninja_url "https://github.com/ninja-build/ninja/releases/download/v${ninja_version}/ninja-${ninja_suffix}")
@@ -98,8 +98,8 @@ jobs:
           )
         endif()
 
-    - name: Install Clang 14
-      id: install_clang_11
+    - name: Install Clang 17
+      id: install_clang_17
       if: startsWith(matrix.config.os, 'ubuntu') && startsWith(matrix.config.cxx, 'clang++-')
       shell: bash
       working-directory: ${{ env.HOME }}
@@ -109,9 +109,9 @@ jobs:
         sudo ./llvm.sh ${{ matrix.config.clang_version }}
         sudo apt-get install -y libunwind-${{ matrix.config.clang_version }}-dev libunwind-${{ matrix.config.clang_version }}
 
-    - name: Install g++ 11
-      id: install_gcc_11
-      if: startsWith(matrix.config.os, 'ubuntu') && ( matrix.config.cxx == 'g++-11' )
+    - name: Install g++ 13
+      id: install_gcc_13
+      if: startsWith(matrix.config.os, 'ubuntu') && ( matrix.config.cxx == 'g++-13' )
       shell: bash
       working-directory: ${{ env.HOME }}
       env:
@@ -121,7 +121,7 @@ jobs:
         sudo add-apt-repository ppa:ubuntu-toolchain-r/test
         sudo apt-get update
         sudo apt-get install g++-${{ matrix.config.gcc_version }}
-        sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-11 100
+        sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-13 100
 
     - name: Install libc++
       id: install_libcxx
diff --git a/01.01-variadicTemplateSum2/CMakeLists.txt b/01.01-variadicTemplateSum2/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/01.01-variadicTemplateSum2/CMakeLists.txt
+++ b/01.01-variadicTemplateSum2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/01.02-variableTemplate0/CMakeLists.txt b/01.02-variableTemplate0/CMakeLists.txt
index 14b1ad9..2811d7c 100644
--- a/01.02-variableTemplate0/CMakeLists.txt
+++ b/01.02-variableTemplate0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 14)
diff --git a/01.05-variadicTemplateSum3/CMakeLists.txt b/01.05-variadicTemplateSum3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.05-variadicTemplateSum3/CMakeLists.txt
+++ b/01.05-variadicTemplateSum3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.06-simpleRequirement0/CMakeLists.txt b/01.06-simpleRequirement0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.06-simpleRequirement0/CMakeLists.txt
+++ b/01.06-simpleRequirement0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.06-simpleRequirement0/main.cpp b/01.06-simpleRequirement0/main.cpp
index 97c4631..6b2e375 100644
--- a/01.06-simpleRequirement0/main.cpp
+++ b/01.06-simpleRequirement0/main.cpp
@@ -8,12 +8,11 @@ template<typename T, typename... Ts>
 constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;
 
 template<typename... Args>
-requires
+  requires
 
-  requires(Args... args)
-{
-  (... + args);  // #C SR: args  provides +
-}
+  requires(Args... args) {
+    (... + args);  // #C SR: args  provides +
+  }
 
 auto add(const Args&... args)
 {
diff --git a/01.07-nestedRequirement0/CMakeLists.txt b/01.07-nestedRequirement0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.07-nestedRequirement0/CMakeLists.txt
+++ b/01.07-nestedRequirement0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.08-compoundRequirement0/CMakeLists.txt b/01.08-compoundRequirement0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.08-compoundRequirement0/CMakeLists.txt
+++ b/01.08-compoundRequirement0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.08-compoundRequirement0/main.cpp b/01.08-compoundRequirement0/main.cpp
index 28a0f78..6c0d85e 100644
--- a/01.08-compoundRequirement0/main.cpp
+++ b/01.08-compoundRequirement0/main.cpp
@@ -34,7 +34,7 @@ requires(Args... args)
 }
 
 
-auto add(Args&&... args)
+auto add(Args&&... args) noexcept
 {
   return (... + args);
 }
diff --git a/01.09-typeRequirement0/CMakeLists.txt b/01.09-typeRequirement0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.09-typeRequirement0/CMakeLists.txt
+++ b/01.09-typeRequirement0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.09-typeRequirement0/main.cpp b/01.09-typeRequirement0/main.cpp
index 490bf54..a1c7cd3 100644
--- a/01.09-typeRequirement0/main.cpp
+++ b/01.09-typeRequirement0/main.cpp
@@ -5,8 +5,7 @@
 #include <vector>
 
 template<typename T>
-concept containerTypes = requires(T t)
-{  // #A Testing for various types in T
+concept containerTypes = requires(T t) {  // #A Testing for various types in T
   typename T::value_type;
   typename T::size_type;
   typename T::allocator_type;
diff --git a/01.10-compoundRequirement1/CMakeLists.txt b/01.10-compoundRequirement1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.10-compoundRequirement1/CMakeLists.txt
+++ b/01.10-compoundRequirement1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.10-compoundRequirement1/main.cpp b/01.10-compoundRequirement1/main.cpp
index 103acbf..475f89f 100644
--- a/01.10-compoundRequirement1/main.cpp
+++ b/01.10-compoundRequirement1/main.cpp
@@ -27,7 +27,7 @@ requires  requires(Args... args)
   requires sizeof...(Args) > 1;
   { (... + args) } noexcept -> same_as<first_arg_t<Args...>>;
 }
-auto Add(Args&&... args)
+auto Add(Args&&... args) noexcept
 {
   return (... + args);
 }
diff --git a/01.11-compoundRequirement2/CMakeLists.txt b/01.11-compoundRequirement2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.11-compoundRequirement2/CMakeLists.txt
+++ b/01.11-compoundRequirement2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.11-compoundRequirement2/main.cpp b/01.11-compoundRequirement2/main.cpp
index f168835..4eb9897 100644
--- a/01.11-compoundRequirement2/main.cpp
+++ b/01.11-compoundRequirement2/main.cpp
@@ -30,7 +30,7 @@ concept Addable = requires(Args... args)
 
 template<typename... Args> 
 requires Addable<Args...>
-auto Add(Args&&... args)
+auto Add(Args&&... args) noexcept
 {
   return (... + args);
 }
diff --git a/01.12-testingRequirements0/CMakeLists.txt b/01.12-testingRequirements0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.12-testingRequirements0/CMakeLists.txt
+++ b/01.12-testingRequirements0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.12-testingRequirements0/main.cpp b/01.12-testingRequirements0/main.cpp
index 0762fc2..5c3d4cc 100644
--- a/01.12-testingRequirements0/main.cpp
+++ b/01.12-testingRequirements0/main.cpp
@@ -21,19 +21,17 @@ template<typename... Args>
 using first_arg_t = typename first_arg<Args...>::type;
 
 template<typename... Args>
-concept Addable = requires(Args... args)
-{
+concept Addable = requires(Args... args) {
   (... + args);
   requires are_same_v<Args...>;
   requires sizeof...(Args) > 1;
   {
     (... + args)
-  }
-  noexcept->same_as<first_arg_t<Args...>>;
+  } noexcept -> same_as<first_arg_t<Args...>>;
 };
 
 template<typename... Args>
-requires Addable<Args...>
+  requires Addable<Args...>
 auto Add(Args&&... args)
 {
   return (... + args);
@@ -44,15 +42,15 @@ auto Add(Args&&... args)
 template<bool nexcept, bool operatorPlus, bool validReturnType>
 struct Stub {
   // #B Operator plus with controlled noexcept can be enabled
-  Stub& operator+(const Stub& rhs) noexcept(nexcept) requires(
-    operatorPlus&& validReturnType)
+  Stub& operator+(const Stub& rhs) noexcept(nexcept)
+    requires(operatorPlus && validReturnType)
   {
     return *this;
   }
 
   // #C Operator plus with invalid return type
-  int operator+(const Stub& rhs) noexcept(nexcept) requires(
-    operatorPlus && not validReturnType)
+  int operator+(const Stub& rhs) noexcept(nexcept)
+    requires(operatorPlus && not validReturnType)
   {
     return {};
   }
diff --git a/01.14-invocable0/CMakeLists.txt b/01.14-invocable0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.14-invocable0/CMakeLists.txt
+++ b/01.14-invocable0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.14-invocable0/main.cpp b/01.14-invocable0/main.cpp
index a55fed1..e54a854 100644
--- a/01.14-invocable0/main.cpp
+++ b/01.14-invocable0/main.cpp
@@ -18,5 +18,5 @@ void DoLocked(T&& f)
 
 int main()
 {
-  DoLocked([] { printf("hello\n"); });
+  DoLocked([] { puts("hello"); });
 }
\ No newline at end of file
diff --git a/01.15-invocable1/CMakeLists.txt b/01.15-invocable1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.15-invocable1/CMakeLists.txt
+++ b/01.15-invocable1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.15-invocable1/main.cpp b/01.15-invocable1/main.cpp
index f0d173f..c4776f5 100644
--- a/01.15-invocable1/main.cpp
+++ b/01.15-invocable1/main.cpp
@@ -19,5 +19,5 @@ void DoLocked(std::invocable auto&& f)
 
 int main()
 {
-  DoLocked([] { printf("hello\n"); });
+  DoLocked([] { puts("hello"); });
 }
\ No newline at end of file
diff --git a/01.16-constexprFunctionInConcept0/CMakeLists.txt b/01.16-constexprFunctionInConcept0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.16-constexprFunctionInConcept0/CMakeLists.txt
+++ b/01.16-constexprFunctionInConcept0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.18-vectorsSize0/CMakeLists.txt b/01.18-vectorsSize0/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/01.18-vectorsSize0/CMakeLists.txt
+++ b/01.18-vectorsSize0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/01.21-vectorsSize1/CMakeLists.txt b/01.21-vectorsSize1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.21-vectorsSize1/CMakeLists.txt
+++ b/01.21-vectorsSize1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.22-validateInDebugModeIfExists0/CMakeLists.txt b/01.22-validateInDebugModeIfExists0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.22-validateInDebugModeIfExists0/CMakeLists.txt
+++ b/01.22-validateInDebugModeIfExists0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.22-validateInDebugModeIfExists0/main.cpp b/01.22-validateInDebugModeIfExists0/main.cpp
index 7768dd4..33590b6 100644
--- a/01.22-validateInDebugModeIfExists0/main.cpp
+++ b/01.22-validateInDebugModeIfExists0/main.cpp
@@ -4,10 +4,7 @@
 #include <cstdio>
 
 template<typename T>
-concept SupportsValidation = requires(T t)
-{
-  t.validate();
-};
+concept SupportsValidation = requires(T t) { t.validate(); };
 
 template<typename T>
 void Send(const T& data)
diff --git a/01.24-optional0/CMakeLists.txt b/01.24-optional0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/01.24-optional0/CMakeLists.txt
+++ b/01.24-optional0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/01.26-optional1/CMakeLists.txt b/01.26-optional1/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/01.26-optional1/CMakeLists.txt
+++ b/01.26-optional1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/01.27-optional2/CMakeLists.txt b/01.27-optional2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.27-optional2/CMakeLists.txt
+++ b/01.27-optional2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.27-optional2/main.cpp b/01.27-optional2/main.cpp
index 0849dff..eb8c108 100644
--- a/01.27-optional2/main.cpp
+++ b/01.27-optional2/main.cpp
@@ -8,13 +8,13 @@ class optional {
 public:
   optional() = default;
 
-  optional(
-    const optional&) requires std::is_copy_constructible_v<T>;
+  optional(const optional&)
+    requires std::is_copy_constructible_v<T>;
 };
 
 template<typename T>
-optional<T>::optional(
-  const optional<T>&) requires std::is_copy_constructible_v<T>
+optional<T>::optional(const optional<T>&)
+  requires std::is_copy_constructible_v<T>
 {}
 
 struct NotCopyable {
diff --git a/01.28-optional3/CMakeLists.txt b/01.28-optional3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.28-optional3/CMakeLists.txt
+++ b/01.28-optional3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.28-optional3/main.cpp b/01.28-optional3/main.cpp
index 4b9f957..cc6dde0 100644
--- a/01.28-optional3/main.cpp
+++ b/01.28-optional3/main.cpp
@@ -23,15 +23,16 @@ class optional {
   // The real constructor is omitted here because it
   // doesn't matter
 
-  ~optional() requires(not std::is_trivially_destructible_v<T>)
+  ~optional()
+    requires(not std::is_trivially_destructible_v<T>)
   {
     if(has_value) { value.as()->~T(); }
   }
 
   ~optional() = default;
 
-  optional(
-    const optional&) requires std::is_copy_constructible_v<T>
+  optional(const optional&)
+    requires std::is_copy_constructible_v<T>
   = default;
 
 private:
@@ -56,7 +57,6 @@ static_assert(std::is_trivially_destructible_v<storage_t<int>>);
 
 int main()
 {
-#if not defined(__clang__)
   static_assert(
     not std::is_copy_constructible_v<optional<NotCopyable>>);
   static_assert(std::is_copy_constructible_v<optional<int>>);
@@ -65,7 +65,4 @@ int main()
                 optional<Not_TriviallyDestructible>>);
   static_assert(
     std::is_trivially_destructible_v<optional<int>>);
-#else
-#  pragma message("not supported")
-#endif
 }
\ No newline at end of file
diff --git a/01.29-optional4/CMakeLists.txt b/01.29-optional4/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.29-optional4/CMakeLists.txt
+++ b/01.29-optional4/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.29-optional4/main.cpp b/01.29-optional4/main.cpp
index 787807a..ba01251 100644
--- a/01.29-optional4/main.cpp
+++ b/01.29-optional4/main.cpp
@@ -13,14 +13,11 @@ struct COMLike {
 
 void COMLike::Release()
 {
-  printf("release\n");
+  puts("release");
 }
 
 template<typename T>
-concept HasRelease = requires(T t)
-{
-  t.Release();
-};
+concept HasRelease = requires(T t) { t.Release(); };
 
 #if not defined(_MSC_VER) && not defined(__clang__)
 template<typename T>
@@ -29,14 +26,16 @@ class optional {
   optional() = default;
 
   // #A Only if not trivially destructible
-  ~optional() requires(not std::is_trivially_destructible_v<T>)
+  ~optional()
+    requires(not std::is_trivially_destructible_v<T>)
   {
     if(has_value) { value.as()->~T(); }
   }
 
   // #B If not trivially destructible and has Release method
-  ~optional() requires(not std::is_trivially_destructible_v<T> and
-                       HasRelease<T>)
+  ~optional()
+    requires(not std::is_trivially_destructible_v<T> and
+             HasRelease<T>)
   {
     if(has_value) {
       value.as()->Release();
@@ -46,7 +45,8 @@ class optional {
 
   ~optional() = default;
 
-  optional(const optional&) requires std::is_copy_constructible_v<T>
+  optional(const optional&)
+    requires std::is_copy_constructible_v<T>
   = default;
 
 private:
diff --git a/01.32-optional5/CMakeLists.txt b/01.32-optional5/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.32-optional5/CMakeLists.txt
+++ b/01.32-optional5/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.32-optional5/main.cpp b/01.32-optional5/main.cpp
index b8ca6ac..1116cc1 100644
--- a/01.32-optional5/main.cpp
+++ b/01.32-optional5/main.cpp
@@ -13,16 +13,12 @@ struct COMLike {
 
 void COMLike::Release()
 {
-  printf("release\n");
+  puts("release");
 }
 
 template<typename T>
-concept HasRelease = requires(T t)
-{
-  t.Release();
-};
+concept HasRelease = requires(T t) { t.Release(); };
 
-#if not defined(__clang__)
 template<typename T>
 concept NotTriviallyDestructible =
   not std::is_trivially_destructible_v<T>;
@@ -33,16 +29,17 @@ class optional {
   optional() = default;
 
   // #A Only if not trivially destructible
-  ~optional() requires NotTriviallyDestructible<T>;
+  ~optional()
+    requires NotTriviallyDestructible<T>;
 
   // #B If not trivially destructible and has Release method
-  ~optional() requires NotTriviallyDestructible<T> and
-    HasRelease<T>;
+  ~optional()
+    requires NotTriviallyDestructible<T> and HasRelease<T>;
 
   ~optional() = default;
 
-  optional(
-    const optional&) requires std::is_copy_constructible_v<T>
+  optional(const optional&)
+    requires std::is_copy_constructible_v<T>
   = default;
 
 private:
@@ -66,14 +63,15 @@ class optional {
 };
 
 template<typename T>
-optional<T>::~optional() requires NotTriviallyDestructible<T>
+optional<T>::~optional()
+  requires NotTriviallyDestructible<T>
 {
   if(has_value) { value.as()->~T(); }
 }
 
 template<typename T>
-optional<T>::~optional() requires NotTriviallyDestructible<T> &&
-  HasRelease<T>
+optional<T>::~optional()
+  requires NotTriviallyDestructible<T> && HasRelease<T>
 {
   if(has_value) {
     value.as()->Release();
@@ -81,8 +79,6 @@ optional<T>::~optional() requires NotTriviallyDestructible<T> &&
   }
 }
 
-#endif
-
 struct NotCopyable {
   NotCopyable(const NotCopyable&)            = delete;
   NotCopyable& operator=(const NotCopyable&) = delete;
@@ -97,7 +93,6 @@ static_assert(not std::is_trivially_destructible_v<
 
 int main()
 {
-#if not defined(__clang__)
   static_assert(
     not std::is_copy_constructible_v<optional<NotCopyable>>);
   static_assert(std::is_copy_constructible_v<optional<int>>);
@@ -109,8 +104,4 @@ int main()
 
   optional<Not_TriviallyDestructible> no{};
   optional<COMLike>                   o{};
-
-#else
-#  pragma message("not supported")
-#endif
 }
\ No newline at end of file
diff --git a/01.33-optional6/CMakeLists.txt b/01.33-optional6/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.33-optional6/CMakeLists.txt
+++ b/01.33-optional6/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.33-optional6/main.cpp b/01.33-optional6/main.cpp
index 2ade93c..a6487e3 100644
--- a/01.33-optional6/main.cpp
+++ b/01.33-optional6/main.cpp
@@ -13,7 +13,7 @@ struct COMLike {
 
 void COMLike::Release()
 {
-  printf("release\n");
+  puts("release");
 }
 
 struct COMLikeTrivial {
@@ -24,16 +24,12 @@ struct COMLikeTrivial {
 
 void COMLikeTrivial::Release()
 {
-  printf("release trivial\n");
+  puts("release trivial");
 }
 
 template<typename T>
-concept HasRelease = requires(T t)
-{
-  t.Release();
-};
+concept HasRelease = requires(T t) { t.Release(); };
 
-#if not defined(__clang__)
 template<typename T>
 concept NotTriviallyDestructible =
   not std::is_trivially_destructible_v<T>;
@@ -44,22 +40,24 @@ class optional {
   optional() = default;
 
   // #A Only if not trivially destructible
-  ~optional() requires NotTriviallyDestructible<T>;
+  ~optional()
+    requires NotTriviallyDestructible<T>;
 
   // #B If not trivially destructible and has Release method
-  ~optional() requires NotTriviallyDestructible<T> and
-    HasRelease<T>;
+  ~optional()
+    requires NotTriviallyDestructible<T> and HasRelease<T>;
 
   // #C Trivial and has Release method
-  ~optional() requires HasRelease<T>
+  ~optional()
+    requires HasRelease<T>
   {
     if(has_value) { value.as()->Release(); }
   }
 
   ~optional() = default;
 
-  optional(
-    const optional&) requires std::is_copy_constructible_v<T>
+  optional(const optional&)
+    requires std::is_copy_constructible_v<T>
   = default;
 
 private:
@@ -83,21 +81,21 @@ class optional {
 };
 
 template<typename T>
-optional<T>::~optional() requires NotTriviallyDestructible<T>
+optional<T>::~optional()
+  requires NotTriviallyDestructible<T>
 {
   if(has_value) { value.as()->~T(); }
 }
 
 template<typename T>
-optional<T>::~optional() requires NotTriviallyDestructible<T> &&
-  HasRelease<T>
+optional<T>::~optional()
+  requires NotTriviallyDestructible<T> && HasRelease<T>
 {
   if(has_value) {
     value.as()->Release();
     value.as()->~T();
   }
 }
-#endif
 
 struct NotCopyable {
   NotCopyable(const NotCopyable&)            = delete;
@@ -115,7 +113,6 @@ static_assert(not std::is_trivially_destructible_v<
 
 int main()
 {
-#if not defined(__clang__)
   static_assert(
     not std::is_copy_constructible_v<optional<NotCopyable>>);
   static_assert(std::is_copy_constructible_v<optional<int>>);
@@ -131,8 +128,4 @@ int main()
   optional<COMLike>                   o{};
   optional<COMLikeTrivial>            ot{};
   optional<TriviallyDestructible>     otd{};
-
-#else
-#  pragma message("not supported")
-#endif
 }
\ No newline at end of file
diff --git a/01.34-isSameConcept0/CMakeLists.txt b/01.34-isSameConcept0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.34-isSameConcept0/CMakeLists.txt
+++ b/01.34-isSameConcept0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.34-isSameConcept0/main.cpp b/01.34-isSameConcept0/main.cpp
index 088fb98..256f1df 100644
--- a/01.34-isSameConcept0/main.cpp
+++ b/01.34-isSameConcept0/main.cpp
@@ -10,14 +10,14 @@ template<typename T>
 concept AlwaysTrue = true;
 
 template<typename T, typename U>
-requires IsSame<T, U>
+  requires IsSame<T, U>
 auto add(const T& t, const U& u)
 {
   return t + u;
 }
 
 template<typename T, typename U>
-requires IsSame<T, U> and AlwaysTrue<T>
+  requires IsSame<T, U> and AlwaysTrue<T>
 auto add(const T& t, const U& u)
 {
   return t + u;
diff --git a/01.36-isSameConcept1/CMakeLists.txt b/01.36-isSameConcept1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.36-isSameConcept1/CMakeLists.txt
+++ b/01.36-isSameConcept1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.36-isSameConcept1/main.cpp b/01.36-isSameConcept1/main.cpp
index 88bfe13..9bfc3ca 100644
--- a/01.36-isSameConcept1/main.cpp
+++ b/01.36-isSameConcept1/main.cpp
@@ -11,7 +11,7 @@ concept AlwaysTrue = true;
 
 template<typename T, typename U>
 // #A The arguments are swapped T, U vs U, T
-requires IsSame<U, T>
+  requires IsSame<U, T>
 auto add(const T& t, const U& u)
 {
   return t + u;
@@ -19,7 +19,7 @@ auto add(const T& t, const U& u)
 
 template<typename T, typename U>
 // #B The arguments remain unchanged
-requires IsSame<T, U> and AlwaysTrue<T>
+  requires IsSame<T, U> and AlwaysTrue<T>
 auto add(const T& t, const U& u)
 {
   return t + u;
diff --git a/01.37-isSameConcept2/CMakeLists.txt b/01.37-isSameConcept2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.37-isSameConcept2/CMakeLists.txt
+++ b/01.37-isSameConcept2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.37-isSameConcept2/main.cpp b/01.37-isSameConcept2/main.cpp
index b5493b2..f8c1dd8 100644
--- a/01.37-isSameConcept2/main.cpp
+++ b/01.37-isSameConcept2/main.cpp
@@ -14,7 +14,7 @@ concept AlwaysTrue = true;
 
 template<typename T, typename U>
 // #A The arguments are swapped T, U vs U, T
-requires IsSame<U, T>
+  requires IsSame<U, T>
 auto add(const T& t, const U& u)
 {
   return t + u;
@@ -22,7 +22,7 @@ auto add(const T& t, const U& u)
 
 template<typename T, typename U>
 // #B The arguments remain unchanged
-requires IsSame<T, U> and AlwaysTrue<T>
+  requires IsSame<T, U> and AlwaysTrue<T>
 auto add(const T& t, const U& u)
 {
   return t + u;
diff --git a/01.38-isSameConcept3/CMakeLists.txt b/01.38-isSameConcept3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.38-isSameConcept3/CMakeLists.txt
+++ b/01.38-isSameConcept3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.38-isSameConcept3/main.cpp b/01.38-isSameConcept3/main.cpp
index b04e0bc..8a8473b 100644
--- a/01.38-isSameConcept3/main.cpp
+++ b/01.38-isSameConcept3/main.cpp
@@ -14,16 +14,16 @@ concept AlwaysTrue = true;
 
 template<typename T, typename U>
 // #A Inverting IsSame with not
-requires(not IsSame<T, U>) auto add(const T& t, const U& u)
+  requires(not IsSame<T, U>)
+auto add(const T& t, const U& u)
 {
   return t + u;
 }
 
 template<typename T, typename U>
 // #B Inverting IsSame with not
-requires((not IsSame<T, U>)and AlwaysTrue<T>) auto add(
-  const T& t,
-  const U& u)
+  requires((not IsSame<T, U>) and AlwaysTrue<T>)
+auto add(const T& t, const U& u)
 {
   return t + u;
 }
diff --git a/01.40-printSorted0/CMakeLists.txt b/01.40-printSorted0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/01.40-printSorted0/CMakeLists.txt
+++ b/01.40-printSorted0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/01.42-printSorted1/CMakeLists.txt b/01.42-printSorted1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/01.42-printSorted1/CMakeLists.txt
+++ b/01.42-printSorted1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/01.42-printSorted1/main.cpp b/01.42-printSorted1/main.cpp
index 2476be7..ee09499 100644
--- a/01.42-printSorted1/main.cpp
+++ b/01.42-printSorted1/main.cpp
@@ -9,10 +9,7 @@
 #include <vector>
 
 template<class I>
-concept random_access_iterator = not requires(I t)
-{
-  t.sort();
-};
+concept random_access_iterator = not requires(I t) { t.sort(); };
 
 template<random_access_iterator T>
 void PrintSorted(T c)
@@ -32,10 +29,7 @@ void sortedVector()
 }
 
 template<typename T>
-concept HasSortMethod = requires(T t)
-{
-  t.sort();
-};
+concept HasSortMethod = requires(T t) { t.sort(); };
 
 template<HasSortMethod T>
 void PrintSorted(T c)
diff --git a/02.01-limitlessSequenceWithoutCoroutines0/CMakeLists.txt b/02.01-limitlessSequenceWithoutCoroutines0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/02.01-limitlessSequenceWithoutCoroutines0/CMakeLists.txt
+++ b/02.01-limitlessSequenceWithoutCoroutines0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/02.03-limitlessSequenceWithFunctionTemplate0/CMakeLists.txt b/02.03-limitlessSequenceWithFunctionTemplate0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/02.03-limitlessSequenceWithFunctionTemplate0/CMakeLists.txt
+++ b/02.03-limitlessSequenceWithFunctionTemplate0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/02.04-coroutineLimitlessSequence0/CMakeLists.txt b/02.04-coroutineLimitlessSequence0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/02.04-coroutineLimitlessSequence0/CMakeLists.txt
+++ b/02.04-coroutineLimitlessSequence0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/02.08-parsingDataStream0/CMakeLists.txt b/02.08-parsingDataStream0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/02.08-parsingDataStream0/CMakeLists.txt
+++ b/02.08-parsingDataStream0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/02.08-parsingDataStream0/main.cpp b/02.08-parsingDataStream0/main.cpp
index 248107c..947d1ad 100644
--- a/02.08-parsingDataStream0/main.cpp
+++ b/02.08-parsingDataStream0/main.cpp
@@ -68,7 +68,7 @@ int main()
   auto frameCompleteHandler = [](std::string& res) { printf("CCCB: %s\n", res.c_str()); };
   for(const auto& b : fakeBytes1) { ProcessNextByte(b, frameCompleteHandler); }
 
-  printf("----------\n");
+  puts("----------");
 
   const std::vector<byte> fakeBytes2{
     byte{'W'}, byte{'o'}, byte{'r'}, byte{'l'}, byte{'d'}, ESC, SOF, byte{0x99}};
diff --git a/02.10-coroutineParsingDataStream0/CMakeLists.txt b/02.10-coroutineParsingDataStream0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/02.10-coroutineParsingDataStream0/CMakeLists.txt
+++ b/02.10-coroutineParsingDataStream0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/02.10-coroutineParsingDataStream0/main.cpp b/02.10-coroutineParsingDataStream0/main.cpp
index 2581a1c..45f9fb0 100644
--- a/02.10-coroutineParsingDataStream0/main.cpp
+++ b/02.10-coroutineParsingDataStream0/main.cpp
@@ -8,6 +8,7 @@
 #include <optional>
 #include <string>
 #include <type_traits>
+#include <utility>
 #include <vector>
 #include <version>
 
diff --git a/02.18-coroutineParsingDataStream1/CMakeLists.txt b/02.18-coroutineParsingDataStream1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/02.18-coroutineParsingDataStream1/CMakeLists.txt
+++ b/02.18-coroutineParsingDataStream1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/02.18-coroutineParsingDataStream1/main.cpp b/02.18-coroutineParsingDataStream1/main.cpp
index 32b435c..8ecf8c2 100644
--- a/02.18-coroutineParsingDataStream1/main.cpp
+++ b/02.18-coroutineParsingDataStream1/main.cpp
@@ -8,6 +8,7 @@
 #include <optional>
 #include <string>
 #include <type_traits>
+#include <utility>
 #include <vector>
 #include <version>
 
diff --git a/02.24-coroutineParsingDataStreamCustomAllocator0/CMakeLists.txt b/02.24-coroutineParsingDataStreamCustomAllocator0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/02.24-coroutineParsingDataStreamCustomAllocator0/CMakeLists.txt
+++ b/02.24-coroutineParsingDataStreamCustomAllocator0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/02.24-coroutineParsingDataStreamCustomAllocator0/main.cpp b/02.24-coroutineParsingDataStreamCustomAllocator0/main.cpp
index 7c8ee00..b9d6344 100644
--- a/02.24-coroutineParsingDataStreamCustomAllocator0/main.cpp
+++ b/02.24-coroutineParsingDataStreamCustomAllocator0/main.cpp
@@ -8,6 +8,7 @@
 #include <optional>
 #include <string>
 #include <type_traits>
+#include <utility>
 #include <vector>
 #include <version>
 
diff --git a/02.25-coroutineParsingDataStreamCustomAllocator1/CMakeLists.txt b/02.25-coroutineParsingDataStreamCustomAllocator1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/02.25-coroutineParsingDataStreamCustomAllocator1/CMakeLists.txt
+++ b/02.25-coroutineParsingDataStreamCustomAllocator1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/02.25-coroutineParsingDataStreamCustomAllocator1/main.cpp b/02.25-coroutineParsingDataStreamCustomAllocator1/main.cpp
index 186f5e0..3116467 100644
--- a/02.25-coroutineParsingDataStreamCustomAllocator1/main.cpp
+++ b/02.25-coroutineParsingDataStreamCustomAllocator1/main.cpp
@@ -8,6 +8,7 @@
 #include <optional>
 #include <string>
 #include <type_traits>
+#include <utility>
 #include <vector>
 #include <version>
 
diff --git a/02.27-coroutineParsingDataStreamException0/CMakeLists.txt b/02.27-coroutineParsingDataStreamException0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/02.27-coroutineParsingDataStreamException0/CMakeLists.txt
+++ b/02.27-coroutineParsingDataStreamException0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/02.27-coroutineParsingDataStreamException0/main.cpp b/02.27-coroutineParsingDataStreamException0/main.cpp
index f42dc33..2208195 100644
--- a/02.27-coroutineParsingDataStreamException0/main.cpp
+++ b/02.27-coroutineParsingDataStreamException0/main.cpp
@@ -9,6 +9,7 @@
 #include <optional>
 #include <string>
 #include <type_traits>
+#include <utility>
 #include <vector>
 #include <version>
 
@@ -64,12 +65,12 @@ struct promise_type_base {
 
   std::suspend_always final_suspend() noexcept
   {
-    printf("final_suspend\n");
+    puts("final_suspend");
     return {};
   }
   G get_return_object()
   {
-    printf("get_return_object\n");
+    puts("get_return_object");
     ThrowIf(Ex::GetReturnObject, "get_return_object");
 
     return G{this};
@@ -77,7 +78,7 @@ struct promise_type_base {
 
   void unhandled_exception()
   {
-    printf("unhandled_exception\n");
+    puts("unhandled_exception");
     if(rethrow) {
       if(2 == rethrow) {
         auto exceptionPtr = std::current_exception();
@@ -93,7 +94,7 @@ struct promise_type_base {
         throw;
       }
     } else {
-      printf("do nothing\n");
+      puts("do nothing");
     }
   }
 
diff --git a/03.01-rangesMotivation0/CMakeLists.txt b/03.01-rangesMotivation0/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/03.01-rangesMotivation0/CMakeLists.txt
+++ b/03.01-rangesMotivation0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/03.02-rangesMotivation1/CMakeLists.txt b/03.02-rangesMotivation1/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/03.02-rangesMotivation1/CMakeLists.txt
+++ b/03.02-rangesMotivation1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/03.03-rangesMotivation2/CMakeLists.txt b/03.03-rangesMotivation2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.03-rangesMotivation2/CMakeLists.txt
+++ b/03.03-rangesMotivation2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.03-rangesMotivation2/main.cpp b/03.03-rangesMotivation2/main.cpp
index e156fec..39ac2a8 100644
--- a/03.03-rangesMotivation2/main.cpp
+++ b/03.03-rangesMotivation2/main.cpp
@@ -1,10 +1,9 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <algorithm>
-#  include <ranges>
-#  include <string>
+#include <algorithm>
+#include <ranges>
+#include <string>
 
 int main()
 {
@@ -12,11 +11,4 @@ int main()
   const std::string secondText{"Bello"};
 
   const bool equal = std::ranges::equal(firstText, secondText);
-}
-#else
-int main()
-{
-
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/03.04-twoStepUsing0/CMakeLists.txt b/03.04-twoStepUsing0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.04-twoStepUsing0/CMakeLists.txt
+++ b/03.04-twoStepUsing0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.04-twoStepUsing0/main.cpp b/03.04-twoStepUsing0/main.cpp
index 8f0f616..f87a5ef 100644
--- a/03.04-twoStepUsing0/main.cpp
+++ b/03.04-twoStepUsing0/main.cpp
@@ -4,8 +4,8 @@
 #include <iostream>
 
 #ifdef WILL_NOT_COMPILE
-struct Container {};    // #A Container without begin
-int* begin(Container);  // #B Free-function begin for Container
+struct Container {};     // #A Container without begin
+int* begin(Container);   // #B Free-function begin for Container
 
 struct OtherContainer {  // #C Container with begin
   int* begin();
diff --git a/03.05-twoStepUsing1/CMakeLists.txt b/03.05-twoStepUsing1/CMakeLists.txt
index 6c3ef8c..7a3382d 100644
--- a/03.05-twoStepUsing1/CMakeLists.txt
+++ b/03.05-twoStepUsing1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
@@ -83,7 +83,8 @@ else()
       
     else()
       add_definitions(-fcoroutines) # required for GCC-10    
-      
+      add_definitions(-Wno-unused-result)
+
     endif()
 endif()
 
diff --git a/03.06-twoStepUsing2/CMakeLists.txt b/03.06-twoStepUsing2/CMakeLists.txt
index 6c3ef8c..7a3382d 100644
--- a/03.06-twoStepUsing2/CMakeLists.txt
+++ b/03.06-twoStepUsing2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
@@ -83,7 +83,8 @@ else()
       
     else()
       add_definitions(-fcoroutines) # required for GCC-10    
-      
+      add_definitions(-Wno-unused-result)
+
     endif()
 endif()
 
diff --git a/03.07-rangesSafety0/CMakeLists.txt b/03.07-rangesSafety0/CMakeLists.txt
index 6c1466a..9a169de 100644
--- a/03.07-rangesSafety0/CMakeLists.txt
+++ b/03.07-rangesSafety0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/03.08-rangesSafety1/CMakeLists.txt b/03.08-rangesSafety1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.08-rangesSafety1/CMakeLists.txt
+++ b/03.08-rangesSafety1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.09-rangesMotivationComposability0/CMakeLists.txt b/03.09-rangesMotivationComposability0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/03.09-rangesMotivationComposability0/CMakeLists.txt
+++ b/03.09-rangesMotivationComposability0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/03.09-rangesMotivationComposability0/main.cpp b/03.09-rangesMotivationComposability0/main.cpp
index 971478f..4f9e1a6 100644
--- a/03.09-rangesMotivationComposability0/main.cpp
+++ b/03.09-rangesMotivationComposability0/main.cpp
@@ -14,8 +14,8 @@ void stl()
 {
   std::vector<int> numbers{2, 3, 4, 5, 6};  // #A
 
-  std::vector<int> oddNumbers{};  // #B
-  std::copy_if(begin(numbers),    // #C
+  std::vector<int> oddNumbers{};            // #B
+  std::copy_if(begin(numbers),              // #C
                end(numbers),
                std::back_inserter(oddNumbers),
                is_odd);
diff --git a/03.10-rangesMotivationComposability1/CMakeLists.txt b/03.10-rangesMotivationComposability1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.10-rangesMotivationComposability1/CMakeLists.txt
+++ b/03.10-rangesMotivationComposability1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.10-rangesMotivationComposability1/main.cpp b/03.10-rangesMotivationComposability1/main.cpp
index eb869da..3666680 100644
--- a/03.10-rangesMotivationComposability1/main.cpp
+++ b/03.10-rangesMotivationComposability1/main.cpp
@@ -1,11 +1,10 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <algorithm>
-#  include <iostream>
-#  include <ranges>
-#  include <vector>
+#include <algorithm>
+#include <iostream>
+#include <ranges>
+#include <vector>
 
 bool is_odd(int num)
 {
@@ -30,10 +29,4 @@ void ranges()
 int main()
 {
   ranges();
-}
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/03.11-aRange0/CMakeLists.txt b/03.11-aRange0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.11-aRange0/CMakeLists.txt
+++ b/03.11-aRange0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.13-rangesCommonView1/CMakeLists.txt b/03.13-rangesCommonView1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.13-rangesCommonView1/CMakeLists.txt
+++ b/03.13-rangesCommonView1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.14-rangesCommonView2/CMakeLists.txt b/03.14-rangesCommonView2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.14-rangesCommonView2/CMakeLists.txt
+++ b/03.14-rangesCommonView2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.14-rangesCommonView2/main.cpp b/03.14-rangesCommonView2/main.cpp
index 1c2a341..076ec98 100644
--- a/03.14-rangesCommonView2/main.cpp
+++ b/03.14-rangesCommonView2/main.cpp
@@ -1,11 +1,10 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <iostream>
-#  include <numeric>
-#  include <ranges>
-#  include <vector>
+#include <iostream>
+#include <numeric>
+#include <ranges>
+#include <vector>
 
 int main()
 {
@@ -17,10 +16,4 @@ int main()
 
   auto res = std::accumulate(rng.begin(), rng.end(), 0);
   std::cout << res << '\n';
-}
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/03.15-rangesProjection0/CMakeLists.txt b/03.15-rangesProjection0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/03.15-rangesProjection0/CMakeLists.txt
+++ b/03.15-rangesProjection0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/03.17-rangesProjection1/CMakeLists.txt b/03.17-rangesProjection1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.17-rangesProjection1/CMakeLists.txt
+++ b/03.17-rangesProjection1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.17-rangesProjection1/main.cpp b/03.17-rangesProjection1/main.cpp
index 16b2372..53c9348 100644
--- a/03.17-rangesProjection1/main.cpp
+++ b/03.17-rangesProjection1/main.cpp
@@ -1,12 +1,11 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <algorithm>
-#  include <iostream>
-#  include <ranges>
-#  include <string>
-#  include <vector>
+#include <algorithm>
+#include <iostream>
+#include <ranges>
+#include <string>
+#include <vector>
 
 int main()
 {
@@ -22,13 +21,4 @@ int main()
   std::ranges::sort(books, {}, &Book::title);
 
   for(const auto& book : books) { std::cout << book.title << '\n'; }
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/03.18-rangesMotivationComposability2/CMakeLists.txt b/03.18-rangesMotivationComposability2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.18-rangesMotivationComposability2/CMakeLists.txt
+++ b/03.18-rangesMotivationComposability2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.18-rangesMotivationComposability2/main.cpp b/03.18-rangesMotivationComposability2/main.cpp
index 197c28c..7465b24 100644
--- a/03.18-rangesMotivationComposability2/main.cpp
+++ b/03.18-rangesMotivationComposability2/main.cpp
@@ -1,11 +1,10 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <algorithm>
-#  include <iostream>
-#  include <ranges>
-#  include <vector>
+#include <algorithm>
+#include <iostream>
+#include <ranges>
+#include <vector>
 
 bool is_odd(int num)
 {
@@ -14,7 +13,7 @@ bool is_odd(int num)
 
 void ranges()
 {
-  std::vector<int> numbers{2, 3, 4, 5, 6};  // #A
+  std::vector<int> numbers{2, 3, 4, 5, 6};            // #A
 
   auto filter = std::views::filter(numbers, is_odd);  // #A
 
@@ -33,10 +32,4 @@ void ranges()
 int main()
 {
   ranges();
-}
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/03.19-rangesCustomAdaptor0/CMakeLists.txt b/03.19-rangesCustomAdaptor0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.19-rangesCustomAdaptor0/CMakeLists.txt
+++ b/03.19-rangesCustomAdaptor0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.19-rangesCustomAdaptor0/main.cpp b/03.19-rangesCustomAdaptor0/main.cpp
index 9c434d4..f411657 100644
--- a/03.19-rangesCustomAdaptor0/main.cpp
+++ b/03.19-rangesCustomAdaptor0/main.cpp
@@ -1,12 +1,11 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <algorithm>
-#  include <iostream>
-#  include <ranges>
-#  include <string>
-#  include <vector>
+#include <algorithm>
+#include <iostream>
+#include <ranges>
+#include <string>
+#include <vector>
 
 int main()
 {
@@ -20,13 +19,4 @@ int main()
       [suffix](auto i) { return std::to_string(i) + suffix; });
 
   for(const auto& e : subView) { std::cout << e << '\n'; }
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/03.20-rangesCustomAdaptor1/CMakeLists.txt b/03.20-rangesCustomAdaptor1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.20-rangesCustomAdaptor1/CMakeLists.txt
+++ b/03.20-rangesCustomAdaptor1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.20-rangesCustomAdaptor1/main.cpp b/03.20-rangesCustomAdaptor1/main.cpp
index d21fb6d..a1a482f 100644
--- a/03.20-rangesCustomAdaptor1/main.cpp
+++ b/03.20-rangesCustomAdaptor1/main.cpp
@@ -1,12 +1,11 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <algorithm>
-#  include <iostream>
-#  include <ranges>
-#  include <string>
-#  include <vector>
+#include <algorithm>
+#include <iostream>
+#include <ranges>
+#include <string>
+#include <vector>
 
 // #B A function returning a callable
 auto addCurrency(const std::string& suffix)
@@ -27,13 +26,4 @@ int main()
     | addCurrency(" €");
 
   for(const auto& e : subView) { std::cout << e << '\n'; }
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/03.22-rangesNamespaces0/CMakeLists.txt b/03.22-rangesNamespaces0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/03.22-rangesNamespaces0/CMakeLists.txt
+++ b/03.22-rangesNamespaces0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/03.22-rangesNamespaces0/main.cpp b/03.22-rangesNamespaces0/main.cpp
index 87dc431..90f771a 100644
--- a/03.22-rangesNamespaces0/main.cpp
+++ b/03.22-rangesNamespaces0/main.cpp
@@ -2,10 +2,10 @@
 // SPDX-License-Identifier: MIT
 
 namespace std {
-  namespace ranges { /* ... */  // improved algorithms and views
-    namespace views {           /* ... */
-    }                           // namespace views
-  }                             // namespace ranges
+  namespace ranges { /* ... */      // improved algorithms and views
+    namespace views {               /* ... */
+    }                               // namespace views
+  }                                 // namespace ranges
 
   namespace views = ranges::views;  // shortcut for the adaptors
 }  // namespace std
diff --git a/03.23-rangesCustomTakeView0/CMakeLists.txt b/03.23-rangesCustomTakeView0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.23-rangesCustomTakeView0/CMakeLists.txt
+++ b/03.23-rangesCustomTakeView0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.23-rangesCustomTakeView0/main.cpp b/03.23-rangesCustomTakeView0/main.cpp
index 270ed7b..c31b807 100644
--- a/03.23-rangesCustomTakeView0/main.cpp
+++ b/03.23-rangesCustomTakeView0/main.cpp
@@ -1,16 +1,15 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <algorithm>
-#  include <ranges>
-#  include <string>
+#include <algorithm>
+#include <ranges>
+#include <string>
 
-#  include <algorithm>
-#  include <cassert>
-#  include <iostream>
-#  include <ranges>
-#  include <vector>
+#include <algorithm>
+#include <cassert>
+#include <iostream>
+#include <ranges>
+#include <vector>
 
 namespace rv = std::ranges::views;
 
@@ -47,12 +46,12 @@ class custom_take_view
 
 template<std::ranges::range R>  // #G Deduction guide
 custom_take_view(R&& base, std::ranges::range_difference_t<R>)
-  ->custom_take_view<std::ranges::views::all_t<R>>;
+  -> custom_take_view<std::ranges::views::all_t<R>>;
 
 namespace details {
   template<std::integral T>  // #A Only integrals
   struct custom_take_range_adaptor_closure {
-    T count_;  // #B Store the count
+    T count_;                // #B Store the count
     constexpr custom_take_range_adaptor_closure(T count)
     : count_{count}
     {}
@@ -99,13 +98,4 @@ int main()
   auto v = n | rv::filter(is_even) | views::custom_take(2);
   std::ranges::copy(v,
                     std::ostream_iterator<int>(std::cout, " "));
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/03.29-rangesCustomTakeView1/CMakeLists.txt b/03.29-rangesCustomTakeView1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/03.29-rangesCustomTakeView1/CMakeLists.txt
+++ b/03.29-rangesCustomTakeView1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/03.29-rangesCustomTakeView1/main.cpp b/03.29-rangesCustomTakeView1/main.cpp
index 4ea09a1..ade2236 100644
--- a/03.29-rangesCustomTakeView1/main.cpp
+++ b/03.29-rangesCustomTakeView1/main.cpp
@@ -1,18 +1,17 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<ranges>) and not defined(__clang__)
-#  include <algorithm>
-#  include <cassert>
-#  include <iostream>
-#  include <ranges>
-#  include <string>
-#  include <vector>
+#include <algorithm>
+#include <cassert>
+#include <iostream>
+#include <ranges>
+#include <string>
+#include <vector>
 
 namespace rv = std::ranges::views;
 
 template<std::ranges::view R>
-requires std::ranges::view<R>
+  requires std::ranges::view<R>
 class custom_take_view
 : public std::ranges::view_interface<custom_take_view<R>> {
 private:
@@ -91,13 +90,4 @@ int main()
   auto v = n | rv::filter(is_even) | views::custom_take(2);
   std::ranges::copy(v,
                     std::ostream_iterator<int>(std::cout, " "));
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/04.01-includeHell0/CMakeLists.txt b/04.01-includeHell0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/04.01-includeHell0/CMakeLists.txt
+++ b/04.01-includeHell0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/04.03-moduleSkeleton0/CMakeLists.txt b/04.03-moduleSkeleton0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/04.03-moduleSkeleton0/CMakeLists.txt
+++ b/04.03-moduleSkeleton0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/04.04-namespaceDetails0/CMakeLists.txt b/04.04-namespaceDetails0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/04.04-namespaceDetails0/CMakeLists.txt
+++ b/04.04-namespaceDetails0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/04.05-namespaceDetails1/CMakeLists.txt b/04.05-namespaceDetails1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/04.05-namespaceDetails1/CMakeLists.txt
+++ b/04.05-namespaceDetails1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/04.06-downWithDebug0/CMakeLists.txt b/04.06-downWithDebug0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/04.06-downWithDebug0/CMakeLists.txt
+++ b/04.06-downWithDebug0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/04.10-downWithDebug1/CMakeLists.txt b/04.10-downWithDebug1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/04.10-downWithDebug1/CMakeLists.txt
+++ b/04.10-downWithDebug1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/04.11-inClassMemberFunction0/CMakeLists.txt b/04.11-inClassMemberFunction0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/04.11-inClassMemberFunction0/CMakeLists.txt
+++ b/04.11-inClassMemberFunction0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/04.12-assertImpl0/CMakeLists.txt b/04.12-assertImpl0/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/04.12-assertImpl0/CMakeLists.txt
+++ b/04.12-assertImpl0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/05.01-stdFmtStockIndex0/CMakeLists.txt b/05.01-stdFmtStockIndex0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.01-stdFmtStockIndex0/CMakeLists.txt
+++ b/05.01-stdFmtStockIndex0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.01-stdFmtStockIndex0/main.cpp b/05.01-stdFmtStockIndex0/main.cpp
index eea7ff1..0976c70 100644
--- a/05.01-stdFmtStockIndex0/main.cpp
+++ b/05.01-stdFmtStockIndex0/main.cpp
@@ -1,13 +1,12 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <format>
-#  include <iomanip>
-#  include <iostream>
-#  include <locale>
-#  include <string>
-#  include <vector>
+#include <format>
+#include <iomanip>
+#include <iostream>
+#include <locale>
+#include <string>
+#include <vector>
 
 class StockIndex {
   std::string mName{};
@@ -101,7 +100,7 @@ void WithIostreamOperator()
 }
 
 namespace withLocale {
-  //#  include "withIostreamOperatorLocale.cpp"
+  // #  include "withIostreamOperatorLocale.cpp"
 }
 
 void WithStdFormat()
@@ -130,11 +129,4 @@ int main()
 
   std::cout << '\n';
   WithStdFormat();
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.03-digitSeparator0/CMakeLists.txt b/05.03-digitSeparator0/CMakeLists.txt
index 14b1ad9..2811d7c 100644
--- a/05.03-digitSeparator0/CMakeLists.txt
+++ b/05.03-digitSeparator0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 14)
diff --git a/05.04-stdFmtStockIndexIostream0/CMakeLists.txt b/05.04-stdFmtStockIndexIostream0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/05.04-stdFmtStockIndexIostream0/CMakeLists.txt
+++ b/05.04-stdFmtStockIndexIostream0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/05.07-stdFmtStockIndexIostreamLocalized0/CMakeLists.txt b/05.07-stdFmtStockIndexIostreamLocalized0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/05.07-stdFmtStockIndexIostreamLocalized0/CMakeLists.txt
+++ b/05.07-stdFmtStockIndexIostreamLocalized0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/05.10-stdFmtEscape0/CMakeLists.txt b/05.10-stdFmtEscape0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.10-stdFmtEscape0/CMakeLists.txt
+++ b/05.10-stdFmtEscape0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.10-stdFmtEscape0/main.cpp b/05.10-stdFmtEscape0/main.cpp
index f5770b5..d962051 100644
--- a/05.10-stdFmtEscape0/main.cpp
+++ b/05.10-stdFmtEscape0/main.cpp
@@ -1,18 +1,13 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <format>
-#  include <iostream>
-#  include <string>
+#include <format>
+#include <iostream>
+#include <string>
 
 int main()
 {
   std::cout << std::format("Having the }} in a {}.", "string");
 
   std::cout << '\n';
-}
-
-#else
-int main() {}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.11-stdFmtLocale0/CMakeLists.txt b/05.11-stdFmtLocale0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.11-stdFmtLocale0/CMakeLists.txt
+++ b/05.11-stdFmtLocale0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.11-stdFmtLocale0/main.cpp b/05.11-stdFmtLocale0/main.cpp
index 8017fde..8a770a0 100644
--- a/05.11-stdFmtLocale0/main.cpp
+++ b/05.11-stdFmtLocale0/main.cpp
@@ -1,18 +1,16 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <clocale>
-#  include <format>
-#  include <iostream>
-#  include <locale>
-#  include <string>
+#include <clocale>
+#include <format>
+#include <iostream>
+#include <locale>
+#include <string>
 
 using namespace std::literals;
 
 int main()
 {
-#  if not(defined(__GNUC__) && !defined(__clang__))
   const double pi = 3.14;
   const int    i  = 1'024;
 
@@ -34,10 +32,4 @@ int main()
   std::cout
     << "\nint with format(...) after setting global loc\n";
   std::cout << std::format("1'024 in US: {:L}\n", i);
-
-#  endif
-}
-
-#else
-int main() {}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.12-stdFmtFloatFormatting0/CMakeLists.txt b/05.12-stdFmtFloatFormatting0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.12-stdFmtFloatFormatting0/CMakeLists.txt
+++ b/05.12-stdFmtFloatFormatting0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.12-stdFmtFloatFormatting0/main.cpp b/05.12-stdFmtFloatFormatting0/main.cpp
index df65e9f..d889249 100644
--- a/05.12-stdFmtFloatFormatting0/main.cpp
+++ b/05.12-stdFmtFloatFormatting0/main.cpp
@@ -1,10 +1,9 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <format>
-#  include <iostream>
-#  include <string>
+#include <format>
+#include <iostream>
+#include <string>
 
 std::string Use()
 {
@@ -21,13 +20,4 @@ int main()
   auto s = Use();
 
   std::cout << s << '\n';
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.13-stdFmtStockIndexCustomFormatter0/CMakeLists.txt b/05.13-stdFmtStockIndexCustomFormatter0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.13-stdFmtStockIndexCustomFormatter0/CMakeLists.txt
+++ b/05.13-stdFmtStockIndexCustomFormatter0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.13-stdFmtStockIndexCustomFormatter0/main.cpp b/05.13-stdFmtStockIndexCustomFormatter0/main.cpp
index def06db..7514247 100644
--- a/05.13-stdFmtStockIndexCustomFormatter0/main.cpp
+++ b/05.13-stdFmtStockIndexCustomFormatter0/main.cpp
@@ -1,13 +1,12 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <format>
-#  include <iomanip>
-#  include <iostream>
-#  include <locale>
-#  include <string>
-#  include <vector>
+#include <format>
+#include <iomanip>
+#include <iostream>
+#include <locale>
+#include <string>
+#include <vector>
 
 class StockIndex {
   std::string mName{};
@@ -57,12 +56,9 @@ std::vector<StockIndex> GetIndices()
 
 template<>
 struct std::formatter<StockIndex> {
-  constexpr auto parse(std::format_parse_context& ctx)
-  {
-    return ctx.begin();
-  }
+  constexpr auto parse(auto& ctx) { return ctx.begin(); }
 
-  auto format(const StockIndex& index, std::format_context& ctx)
+  auto format(const StockIndex& index, auto& ctx) const
   {
     return std::format_to(ctx.out(),
                           "{:10}  {:>8.2f}  {:>6.2f} {:.2f}%",
@@ -78,11 +74,4 @@ int main()
   for(const auto& index : GetIndices()) {
     std::cout << std::format("{}\n", index);
   }
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.15-stdFmtStockIndexCustomFormatter1/CMakeLists.txt b/05.15-stdFmtStockIndexCustomFormatter1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.15-stdFmtStockIndexCustomFormatter1/CMakeLists.txt
+++ b/05.15-stdFmtStockIndexCustomFormatter1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.15-stdFmtStockIndexCustomFormatter1/main.cpp b/05.15-stdFmtStockIndexCustomFormatter1/main.cpp
index 22301a2..35d94dc 100644
--- a/05.15-stdFmtStockIndexCustomFormatter1/main.cpp
+++ b/05.15-stdFmtStockIndexCustomFormatter1/main.cpp
@@ -1,14 +1,13 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <format>
-#  include <iomanip>
-#  include <iostream>
-#  include <locale>
-#  include <string>
-#  include <string_view>
-#  include <vector>
+#include <format>
+#include <iomanip>
+#include <iostream>
+#include <locale>
+#include <string>
+#include <string_view>
+#include <vector>
 
 using namespace std::literals;
 
@@ -64,7 +63,7 @@ struct std::formatter<StockIndex> {
 
   IndexFormat indexFormat{IndexFormat::Normal};
 
-  constexpr auto parse(format_parse_context& ctx)
+  constexpr auto parse(auto& ctx)
   {
     auto it  = ctx.begin();
     auto end = ctx.end();
@@ -86,7 +85,7 @@ struct std::formatter<StockIndex> {
     return it;
   }
 
-  auto format(const StockIndex& index, std::format_context& ctx)
+  auto format(const StockIndex& index, auto& ctx) const
   {
     if(IndexFormat::Short == indexFormat) {
       return std::format_to(ctx.out(),
@@ -123,11 +122,4 @@ int main()
   for(const auto& index : GetIndices()) {
     std::cout << std::format("{:p}\n", index);
   }
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.17-stdFmtStockIndexCustomFormatter2/CMakeLists.txt b/05.17-stdFmtStockIndexCustomFormatter2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.17-stdFmtStockIndexCustomFormatter2/CMakeLists.txt
+++ b/05.17-stdFmtStockIndexCustomFormatter2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.17-stdFmtStockIndexCustomFormatter2/main.cpp b/05.17-stdFmtStockIndexCustomFormatter2/main.cpp
index 5e43431..eff51bc 100644
--- a/05.17-stdFmtStockIndexCustomFormatter2/main.cpp
+++ b/05.17-stdFmtStockIndexCustomFormatter2/main.cpp
@@ -3,14 +3,13 @@
 
 // use with LC_ALL=de_DE.UTF-8 ./a.out
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <format>
-#  include <iomanip>
-#  include <iostream>
-#  include <locale>
-#  include <string>
-#  include <string_view>
-#  include <vector>
+#include <format>
+#include <iomanip>
+#include <iostream>
+#include <locale>
+#include <string>
+#include <string_view>
+#include <vector>
 
 using namespace std::literals;
 
@@ -67,7 +66,7 @@ struct std::formatter<StockIndex> {
   // #A New member to track whether the formatting is  localized
   bool localized = false;
 
-  constexpr auto parse(std::format_parse_context& ctx)
+  constexpr auto parse(auto& ctx)
   {
     auto it = ctx.begin();
 
@@ -97,7 +96,7 @@ struct std::formatter<StockIndex> {
     return it;
   }
 
-  auto format(const StockIndex& index, std::format_context& ctx)
+  auto format(const StockIndex& index, auto& ctx) const
   {
     // #D Add localized
     const auto locFloat{localized ? "L"s : ""s};
@@ -140,11 +139,4 @@ int main()
   for(const auto& index : GetIndices()) {
     std::cout << std::format("{:Lp}\n", index);
   }
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.19-stdFmtFormattingShares0/CMakeLists.txt b/05.19-stdFmtFormattingShares0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.19-stdFmtFormattingShares0/CMakeLists.txt
+++ b/05.19-stdFmtFormattingShares0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.19-stdFmtFormattingShares0/main.cpp b/05.19-stdFmtFormattingShares0/main.cpp
index a2930ea..5b3ec92 100644
--- a/05.19-stdFmtFormattingShares0/main.cpp
+++ b/05.19-stdFmtFormattingShares0/main.cpp
@@ -1,13 +1,12 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <format>
-#  include <iomanip>
-#  include <iostream>
-#  include <locale>
-#  include <string>
-#  include <vector>
+#include <format>
+#include <iomanip>
+#include <iostream>
+#include <locale>
+#include <string>
+#include <vector>
 
 class Share {
   std::string mName;
@@ -60,11 +59,4 @@ int main()
 {
   WithStdFormat();
   WithStdFormatUseArgumentIndex();
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.21-stdFmtFormatTo0/CMakeLists.txt b/05.21-stdFmtFormatTo0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.21-stdFmtFormatTo0/CMakeLists.txt
+++ b/05.21-stdFmtFormatTo0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.21-stdFmtFormatTo0/main.cpp b/05.21-stdFmtFormatTo0/main.cpp
index 6141b45..858de3f 100644
--- a/05.21-stdFmtFormatTo0/main.cpp
+++ b/05.21-stdFmtFormatTo0/main.cpp
@@ -1,12 +1,11 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <array>
-#  include <format>
-#  include <iostream>
-#  include <string_view>
-#  include <vector>
+#include <array>
+#include <format>
+#include <iostream>
+#include <string_view>
+#include <vector>
 
 int main()
 {
@@ -17,11 +16,4 @@ int main()
   for(const auto& c : buffer) { std::cout << c; }
 
   std::cout << '\n';
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.22-stdFmtFormatTo1/CMakeLists.txt b/05.22-stdFmtFormatTo1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.22-stdFmtFormatTo1/CMakeLists.txt
+++ b/05.22-stdFmtFormatTo1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.22-stdFmtFormatTo1/main.cpp b/05.22-stdFmtFormatTo1/main.cpp
index 096395e..117f12c 100644
--- a/05.22-stdFmtFormatTo1/main.cpp
+++ b/05.22-stdFmtFormatTo1/main.cpp
@@ -1,12 +1,11 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <array>
-#  include <format>
-#  include <iostream>
-#  include <string_view>
-#  include <vector>
+#include <array>
+#include <format>
+#include <iostream>
+#include <string_view>
+#include <vector>
 
 using namespace std::literals;
 
@@ -23,11 +22,4 @@ int main()
   for(const auto& c : buffer) { std::cout << c; }
 
   std::cout << '\n';
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.23-stdFmtFormatTo2/CMakeLists.txt b/05.23-stdFmtFormatTo2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.23-stdFmtFormatTo2/CMakeLists.txt
+++ b/05.23-stdFmtFormatTo2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.23-stdFmtFormatTo2/main.cpp b/05.23-stdFmtFormatTo2/main.cpp
index 7b3e1ee..5b40804 100644
--- a/05.23-stdFmtFormatTo2/main.cpp
+++ b/05.23-stdFmtFormatTo2/main.cpp
@@ -1,12 +1,11 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <array>
-#  include <format>
-#  include <iostream>
-#  include <string_view>
-#  include <vector>
+#include <array>
+#include <format>
+#include <iostream>
+#include <string_view>
+#include <vector>
 
 int main()
 {
@@ -16,11 +15,4 @@ int main()
   for(const auto& c : buffer) { std::cout << c; }
 
   std::cout << '\n';
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.24-stdFmtFormatToN0/CMakeLists.txt b/05.24-stdFmtFormatToN0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.24-stdFmtFormatToN0/CMakeLists.txt
+++ b/05.24-stdFmtFormatToN0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.24-stdFmtFormatToN0/main.cpp b/05.24-stdFmtFormatToN0/main.cpp
index 870853f..763eb41 100644
--- a/05.24-stdFmtFormatToN0/main.cpp
+++ b/05.24-stdFmtFormatToN0/main.cpp
@@ -1,11 +1,10 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <array>
-#  include <format>
-#  include <iostream>
-#  include <string_view>
+#include <array>
+#include <format>
+#include <iostream>
+#include <string_view>
 
 int main()
 {
@@ -14,11 +13,4 @@ int main()
     buffer.data(), buffer.size() - 1, "{}, {}", "Hello", "World");
 
   std::cout << buffer.data() << '\n';
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.25-stdFmtCustomLogger0/CMakeLists.txt b/05.25-stdFmtCustomLogger0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.25-stdFmtCustomLogger0/CMakeLists.txt
+++ b/05.25-stdFmtCustomLogger0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.25-stdFmtCustomLogger0/main.cpp b/05.25-stdFmtCustomLogger0/main.cpp
index b7b0814..82cd85c 100644
--- a/05.25-stdFmtCustomLogger0/main.cpp
+++ b/05.25-stdFmtCustomLogger0/main.cpp
@@ -1,26 +1,33 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <array>
-#  include <format>
-#  include <iostream>
-#  include <string_view>
+#include <array>
+#include <format>
+#include <iostream>
+#include <string_view>
 
 using namespace std::literals;
 
-enum LogLevel { Info, Warning, Error };
+enum class LogLevel { Info, Warning, Error };
+
+// Part of C++23's STL
+template<typename T>
+constexpr std::underlying_type_t<T> to_underlying(T value)
+{
+  return static_cast<std::underlying_type_t<T>>(value);
+}
 
 template<>
-struct std::formatter<LogLevel> : std::formatter<const char*> {
-  inline static const char* LEVEL_NAMES[] = {"Info",
-                                             "Warning",
-                                             "Error"};
+struct std::formatter<LogLevel>
+: std::formatter<std::string_view> {
+  inline static std::array levelNames{"Info"sv,
+                                      "Warning"sv,
+                                      "Error"sv};
 
-  auto format(LogLevel c, format_context& ctx)
+  auto format(LogLevel c, auto& ctx) const
   {
-    return std::formatter<const char*>::format(LEVEL_NAMES[c],
-                                               ctx);
+    return std::formatter<std::string_view>::format(
+      levelNames.at(to_underlying(c)), ctx);
   }
 };
 
@@ -43,11 +50,4 @@ int main()
 
   errno = 4;
   log(LogLevel::Error, "Unknown stock, errno {}", errno);
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.27-stdFmtCustomLogger1/CMakeLists.txt b/05.27-stdFmtCustomLogger1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.27-stdFmtCustomLogger1/CMakeLists.txt
+++ b/05.27-stdFmtCustomLogger1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.27-stdFmtCustomLogger1/main.cpp b/05.27-stdFmtCustomLogger1/main.cpp
index 3a227d7..02c0812 100644
--- a/05.27-stdFmtCustomLogger1/main.cpp
+++ b/05.27-stdFmtCustomLogger1/main.cpp
@@ -1,24 +1,32 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
+#if __has_include(<format>)
 #  include <array>
 #  include <format>
 #  include <iostream>
 #  include <string_view>
 
+// Part of C++23's STL
+template<typename T>
+constexpr std::underlying_type_t<T> to_underlying(T value)
+{
+  return static_cast<std::underlying_type_t<T>>(value);
+}
+
 enum LogLevel { Info, Warning, Error };
 
 template<>
-struct std::formatter<LogLevel> : std::formatter<const char*> {
-  inline static const char* LEVEL_NAMES[] = {"Info",
-                                             "Warning",
-                                             "Error"};
+struct std::formatter<LogLevel>
+: std::formatter<std::string_view> {
+  inline static std::array levelNames{"Info"sv,
+                                      "Warning"sv,
+                                      "Error"sv};
 
-  auto format(LogLevel c, format_context& ctx)
+  auto format(LogLevel c, auto& ctx) const
   {
-    return std::formatter<const char*>::format(LEVEL_NAMES[c],
-                                               ctx);
+    return std::formatter<std::string_view>::format(
+      levelNames.at(to_underlying(c)), ctx);
   }
 };
 
@@ -51,8 +59,10 @@ int main()
 }
 
 #else
+
 int main()
 {
 #  pragma message("not supported")
 }
+
 #endif
\ No newline at end of file
diff --git a/05.29-stdFmtCustomLogger2/CMakeLists.txt b/05.29-stdFmtCustomLogger2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.29-stdFmtCustomLogger2/CMakeLists.txt
+++ b/05.29-stdFmtCustomLogger2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.29-stdFmtCustomLogger2/main.cpp b/05.29-stdFmtCustomLogger2/main.cpp
index a7f2804..217e666 100644
--- a/05.29-stdFmtCustomLogger2/main.cpp
+++ b/05.29-stdFmtCustomLogger2/main.cpp
@@ -1,26 +1,32 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(                                             \
-  <format>) and not defined(__clang__) && not (defined(__GNUC__) && !defined(__clang__))
-#  include <algorithm>
-#  include <array>
-#  include <format>
-#  include <iostream>
-#  include <string_view>
+#include <algorithm>
+#include <array>
+#include <format>
+#include <iostream>
+#include <string_view>
+
+// Part of C++23's STL
+template<typename T>
+constexpr std::underlying_type_t<T> to_underlying(T value)
+{
+  return static_cast<std::underlying_type_t<T>>(value);
+}
 
 enum LogLevel { Info, Warning, Error };
 
 template<>
-struct std::formatter<LogLevel> : std::formatter<const char*> {
-  inline static const char* level_names[] = {"Info",
-                                             "Warning",
-                                             "Error"};
+struct std::formatter<LogLevel>
+: std::formatter<std::string_view> {
+  inline static std::array levelNames{"Info"sv,
+                                      "Warning"sv,
+                                      "Error"sv};
 
-  auto format(LogLevel c, format_context& ctx)
+  auto format(LogLevel c, auto& ctx) const
   {
-    return std::formatter<const char*>::format(level_names[c],
-                                               ctx);
+    return std::formatter<std::string_view>::format(
+      levelNames.at(to_underlying(c)), ctx);
   }
 };
 
@@ -81,13 +87,4 @@ int main()
 
   errno = 4;
   log(LogLevel::Error, "Unknown stock, errno:", errno);
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/05.32-stdFmtCustomLogger4/CMakeLists.txt b/05.32-stdFmtCustomLogger4/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/05.32-stdFmtCustomLogger4/CMakeLists.txt
+++ b/05.32-stdFmtCustomLogger4/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/05.32-stdFmtCustomLogger4/main.cpp b/05.32-stdFmtCustomLogger4/main.cpp
index 6aa4258..d1ab8a7 100644
--- a/05.32-stdFmtCustomLogger4/main.cpp
+++ b/05.32-stdFmtCustomLogger4/main.cpp
@@ -1,25 +1,34 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(                                                   \
-  <format>) and not defined(__clang__) && not defined(_MSC_VER)
-#  include <array>
-#  include <chrono>
-#  include <format>
-#  include <iostream>
-#  include <string_view>
+#include <array>
+#include <chrono>
+#include <format>
+#include <iostream>
+#include <string_view>
+
+using namespace std::string_view_literals;
+using namespace std::string_literals;
+
+// Part of C++23's STL
+template<typename T>
+constexpr std::underlying_type_t<T> to_underlying(T value)
+{
+  return static_cast<std::underlying_type_t<T>>(value);
+}
 
 enum LogLevel { Info, Warning, Error };
 
 template<>
-struct std::formatter<LogLevel> : std::formatter<const char*> {
-  inline static const char* level_names[] = {"Info",
-                                             "Warning",
-                                             "Error"};
+struct std::formatter<LogLevel> : std::formatter<std::string_view> {
+  inline static std::array levelNames{"Info"sv,
+                                      "Warning"sv,
+                                      "Error"sv};
 
-  auto format(LogLevel c, format_context& ctx)
+  auto format(LogLevel c, auto& ctx) const
   {
-    return std::formatter<const char*>::format(level_names[c], ctx);
+    return std::formatter<std::string_view>::format(
+      levelNames.at(to_underlying(c)), ctx);
   }
 };
 
@@ -38,17 +47,17 @@ constexpr auto makeBraces()
   return braces;
 }
 
-std::time_t GetTime()
+std::chrono::time_point<std::chrono::system_clock> GetTime()
 {
   //  return std::time(nullptr);
-  return 1605722947;
+  //  return 1605722947;
+  return std::chrono::system_clock::now();
 }
 
 void vlog(std::string_view fmt, std::format_args&& args)
 {
-  const std::time_t t = GetTime();
-  std::clog << std::format("[{:%Y-%m-%d-%H:%M:%S}] ",
-                           *std::localtime(&t))
+  const auto t = GetTime();
+  std::clog << std::format("[{:%Y-%m-%d-%H:%M:%S}] "sv, t)
             << std::vformat(fmt, args);
 }
 
@@ -64,18 +73,11 @@ constexpr void log(LogLevel level, const auto&... args)
 int main()
 {
   int         x{4};
-  std::string share{"Amazon"};
+  std::string share{"Amazon"s};
   double      d{3'117.02};
 
-  log(LogLevel::Info, "Share price", share, "very high:", d);
+  log(LogLevel::Info, "Share price"sv, share, "very high:"sv, d);
 
   errno = 4;
-  log(LogLevel::Error, "Unknown stock, errno", errno);
-}
-
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+  log(LogLevel::Error, "Unknown stock, errno"sv, errno);
+}
\ No newline at end of file
diff --git a/06.01-equalComparOfMRN0/CMakeLists.txt b/06.01-equalComparOfMRN0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/06.01-equalComparOfMRN0/CMakeLists.txt
+++ b/06.01-equalComparOfMRN0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/06.02-equalComparOfMRN1/CMakeLists.txt b/06.02-equalComparOfMRN1/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/06.02-equalComparOfMRN1/CMakeLists.txt
+++ b/06.02-equalComparOfMRN1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/06.04-equalComparOfMRN2/CMakeLists.txt b/06.04-equalComparOfMRN2/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/06.04-equalComparOfMRN2/CMakeLists.txt
+++ b/06.04-equalComparOfMRN2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/06.05-equalComparOfMRN3/CMakeLists.txt b/06.05-equalComparOfMRN3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/06.05-equalComparOfMRN3/CMakeLists.txt
+++ b/06.05-equalComparOfMRN3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/06.06-orderingComparisonString0/CMakeLists.txt b/06.06-orderingComparisonString0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/06.06-orderingComparisonString0/CMakeLists.txt
+++ b/06.06-orderingComparisonString0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/06.06-orderingComparisonString0/main.cpp b/06.06-orderingComparisonString0/main.cpp
index aea2088..88556c9 100644
--- a/06.06-orderingComparisonString0/main.cpp
+++ b/06.06-orderingComparisonString0/main.cpp
@@ -41,22 +41,22 @@ class String {
 
   friend bool operator>(const String& a, const String& b)
   {
-    return Ordering::GreaterThan == Compare(a, b);
+    return (b < a);
   }
 
   friend bool operator<=(const String& a, const String& b)
   {
-    return Ordering::GreaterThan != Compare(a, b);
+    return !(b < a);
   }
 
   friend bool operator>=(const String& a, const String& b)
   {
-    return Ordering::LessThan != Compare(a, b);
+    return !(a < b);
   }
 
 private:
-  const char*  mData;
-  const size_t mLen;
+  const char*  mData{};
+  const size_t mLen{};
 
   // #E The compare function which does the actual comparison.
   static Ordering Compare(const String& a, const String& b);
diff --git a/06.07-orderingComparisonString1/CMakeLists.txt b/06.07-orderingComparisonString1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/06.07-orderingComparisonString1/CMakeLists.txt
+++ b/06.07-orderingComparisonString1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/06.08-orderingComparisonString2/CMakeLists.txt b/06.08-orderingComparisonString2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/06.08-orderingComparisonString2/CMakeLists.txt
+++ b/06.08-orderingComparisonString2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/06.08-orderingComparisonString2/main.cpp b/06.08-orderingComparisonString2/main.cpp
index 6380a81..c9b59d2 100644
--- a/06.08-orderingComparisonString2/main.cpp
+++ b/06.08-orderingComparisonString2/main.cpp
@@ -25,7 +25,7 @@ class String {
   {
     if(mLen != other.mLen) { return false; }  // #B We already had this
 
-    return Compare(*this, other) == 0;  // #C Compare does the work
+    return Compare(*this, other) == 0;        // #C Compare does the work
   }
 
 private:
diff --git a/06.09-orderingComparisonString3/CMakeLists.txt b/06.09-orderingComparisonString4/CMakeLists.txt
similarity index 97%
rename from 06.09-orderingComparisonString3/CMakeLists.txt
rename to 06.09-orderingComparisonString4/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/06.09-orderingComparisonString3/CMakeLists.txt
+++ b/06.09-orderingComparisonString4/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/06.09-orderingComparisonString4/main.cpp b/06.09-orderingComparisonString4/main.cpp
new file mode 100644
index 0000000..7bae787
--- /dev/null
+++ b/06.09-orderingComparisonString4/main.cpp
@@ -0,0 +1,64 @@
+// Copyright (c) Andreas Fertig.
+// SPDX-License-Identifier: MIT
+
+#include <algorithm>
+#include <cassert>
+#include <compare>
+#include <utility>
+
+class String {
+public:
+  template<size_t N>
+  explicit String(const char (&src)[N])
+  : mData{src}
+  , mLen{N}
+  {}
+
+  const char* begin() const { return mData; }
+  const char* end() const { return mData + mLen; }
+
+  auto operator<=>(const String& other) const
+  {
+    return std::lexicographical_compare_three_way(
+      begin(), end(), other.begin(), other.end());
+  }
+
+  bool operator==(const String& other) const
+  {
+    return std::strong_ordering::equal == operator<=>(other);
+  }
+
+private:
+  const char*  mData{};
+  const size_t mLen{};
+};
+
+#define CMP_PRINT(op, expected)                                                \
+  {                                                                            \
+    const bool res = (op);                                                     \
+    assert(res == expected);                                                   \
+  }
+
+int main()
+{
+  const char bufa[]{"Hello"};
+  const char bufc[]{"Hello"};
+
+  String a{bufa};
+  String b{"C++20"};
+
+  String c{bufc};
+  String d{"HellO"};
+  String e{"s"};
+
+  CMP_PRINT(a == b, false);
+  CMP_PRINT(a == c, true);
+  CMP_PRINT(a == d, false);
+
+  CMP_PRINT(a > b, true);
+  CMP_PRINT(a < b, false);
+  CMP_PRINT(a > c, false);
+  CMP_PRINT(a > d, true);
+  CMP_PRINT(a > e, false);
+  CMP_PRINT(a < e, true);
+}
\ No newline at end of file
diff --git a/06.10-spaceshipResultingType0/CMakeLists.txt b/06.10-orderingComparisonString3/CMakeLists.txt
similarity index 97%
rename from 06.10-spaceshipResultingType0/CMakeLists.txt
rename to 06.10-orderingComparisonString3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/06.10-spaceshipResultingType0/CMakeLists.txt
+++ b/06.10-orderingComparisonString3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/06.09-orderingComparisonString3/main.cpp b/06.10-orderingComparisonString3/main.cpp
similarity index 100%
rename from 06.09-orderingComparisonString3/main.cpp
rename to 06.10-orderingComparisonString3/main.cpp
diff --git a/06.11-bcd0/CMakeLists.txt b/06.11-spaceshipResultingType0/CMakeLists.txt
similarity index 97%
rename from 06.11-bcd0/CMakeLists.txt
rename to 06.11-spaceshipResultingType0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/06.11-bcd0/CMakeLists.txt
+++ b/06.11-spaceshipResultingType0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/06.10-spaceshipResultingType0/main.cpp b/06.11-spaceshipResultingType0/main.cpp
similarity index 100%
rename from 06.10-spaceshipResultingType0/main.cpp
rename to 06.11-spaceshipResultingType0/main.cpp
diff --git a/06.12-bcd1/CMakeLists.txt b/06.12-bcd0/CMakeLists.txt
similarity index 97%
rename from 06.12-bcd1/CMakeLists.txt
rename to 06.12-bcd0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/06.12-bcd1/CMakeLists.txt
+++ b/06.12-bcd0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/06.11-bcd0/main.cpp b/06.12-bcd0/main.cpp
similarity index 100%
rename from 06.11-bcd0/main.cpp
rename to 06.12-bcd0/main.cpp
diff --git a/06.13-bcd1/CMakeLists.txt b/06.13-bcd1/CMakeLists.txt
new file mode 100644
index 0000000..03d498a
--- /dev/null
+++ b/06.13-bcd1/CMakeLists.txt
@@ -0,0 +1,90 @@
+# Copyright (c) Andreas Fertig.
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
+
+set(CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_STANDARD 20)
+
+set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
+
+project(${EXEC_NAME} CXX)
+
+# build the filename
+get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
+
+function(check_compiler COMPILER version)
+    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
+        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
+            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
+        endif()
+
+        set(HAVE_COMPILER On PARENT_SCOPE)
+    endif()
+endfunction(check_compiler)
+
+check_compiler("GNU" 10.2)
+check_compiler("Clang" 12.0)
+check_compiler("MSVC" 19.28.29914.0)
+
+
+if(NOT HAVE_COMPILER)
+    message(ERROR "You are using an unsupported compiler!")
+endif()
+
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+    set(IS_GNU On)
+    add_definitions(-DIS_GCC=true)
+else()
+    set(IS_GNU Off)
+    add_definitions(-DIS_GCC=false)
+endif()
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
+    set(IS_CLANG On)
+    add_definitions(-DIS_CLANG=true)
+else()
+    set(IS_CLANG Off)
+    add_definitions(-DIS_CLANG=false)
+endif()
+
+if(MSVC)
+    add_definitions(-DIS_MSVC=true)
+    add_definitions(/WX)
+    add_definitions(/W4)
+    add_definitions(/wd4189)
+    add_definitions(/wd4100)
+    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
+    add_definitions(/wd4267)
+    add_definitions(/wd4505)
+
+    # Use sane and nice C++ for MSVC.
+    # This makes alternative tokens (not, and, ...) as actual keywords and
+    # enables more conformant C++ in general
+    add_definitions(/permissive-)
+
+    
+else()
+    add_definitions(-DIS_MSVC=false)
+    add_definitions(-Werror)
+    add_definitions(-Wall)
+    add_definitions(-Wextra)
+    add_definitions(-Wold-style-cast)
+    add_definitions(-Wno-unused-variable)
+    add_definitions(-Wno-unused-parameter)
+    add_definitions(-Wno-unused-value)
+    add_definitions(-Wno-cpp)
+
+    if(IS_CLANG)
+      add_definitions(-Wno-unused-private-field)
+      add_definitions(-Wno-unneeded-internal-declaration)
+      
+    else()
+      add_definitions(-fcoroutines) # required for GCC-10    
+      
+    endif()
+endif()
+
+add_executable(${EXEC_NAME} main.cpp)
+
diff --git a/06.12-bcd1/main.cpp b/06.13-bcd1/main.cpp
similarity index 100%
rename from 06.12-bcd1/main.cpp
rename to 06.13-bcd1/main.cpp
diff --git a/06.13-bcdConstexpr/CMakeLists.txt b/06.13-bcdConstexpr/CMakeLists.txt
deleted file mode 100644
index ed3d91e..0000000
--- a/06.13-bcdConstexpr/CMakeLists.txt
+++ /dev/null
@@ -1,90 +0,0 @@
-# Copyright (c) Andreas Fertig.
-# SPDX-License-Identifier: MIT
-
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
-
-set(CXX_STANDARD_REQUIRED ON)
-set(CMAKE_CXX_STANDARD 20)
-
-set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
-
-project(${EXEC_NAME} CXX)
-
-# build the filename
-get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
-
-function(check_compiler COMPILER version)
-    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
-        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
-            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
-        endif()
-
-        set(HAVE_COMPILER On PARENT_SCOPE)
-    endif()
-endfunction(check_compiler)
-
-check_compiler("GNU" 10.2)
-check_compiler("Clang" 12.0)
-check_compiler("MSVC" 19.28.29914.0)
-
-
-if(NOT HAVE_COMPILER)
-    message(ERROR "You are using an unsupported compiler!")
-endif()
-
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-    set(IS_GNU On)
-    add_definitions(-DIS_GCC=true)
-else()
-    set(IS_GNU Off)
-    add_definitions(-DIS_GCC=false)
-endif()
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
-    set(IS_CLANG On)
-    add_definitions(-DIS_CLANG=true)
-else()
-    set(IS_CLANG Off)
-    add_definitions(-DIS_CLANG=false)
-endif()
-
-if(MSVC)
-    add_definitions(-DIS_MSVC=true)
-    add_definitions(/WX)
-    add_definitions(/W4)
-    add_definitions(/wd4189)
-    add_definitions(/wd4100)
-    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
-    add_definitions(/wd4267)
-    add_definitions(/wd4505)
-
-    # Use sane and nice C++ for MSVC.
-    # This makes alternative tokens (not, and, ...) as actual keywords and
-    # enables more conformant C++ in general
-    add_definitions(/permissive-)
-
-    
-else()
-    add_definitions(-DIS_MSVC=false)
-    add_definitions(-Werror)
-    add_definitions(-Wall)
-    add_definitions(-Wextra)
-    add_definitions(-Wold-style-cast)
-    add_definitions(-Wno-unused-variable)
-    add_definitions(-Wno-unused-parameter)
-    add_definitions(-Wno-unused-value)
-    add_definitions(-Wno-cpp)
-
-    if(IS_CLANG)
-      add_definitions(-Wno-unused-private-field)
-      add_definitions(-Wno-unneeded-internal-declaration)
-      
-    else()
-      add_definitions(-fcoroutines) # required for GCC-10    
-      
-    endif()
-endif()
-
-add_executable(${EXEC_NAME} main.cpp)
-
diff --git a/06.14-bcdConstexpr/CMakeLists.txt b/06.14-bcdConstexpr/CMakeLists.txt
new file mode 100644
index 0000000..03d498a
--- /dev/null
+++ b/06.14-bcdConstexpr/CMakeLists.txt
@@ -0,0 +1,90 @@
+# Copyright (c) Andreas Fertig.
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
+
+set(CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_STANDARD 20)
+
+set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
+
+project(${EXEC_NAME} CXX)
+
+# build the filename
+get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
+
+function(check_compiler COMPILER version)
+    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
+        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
+            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
+        endif()
+
+        set(HAVE_COMPILER On PARENT_SCOPE)
+    endif()
+endfunction(check_compiler)
+
+check_compiler("GNU" 10.2)
+check_compiler("Clang" 12.0)
+check_compiler("MSVC" 19.28.29914.0)
+
+
+if(NOT HAVE_COMPILER)
+    message(ERROR "You are using an unsupported compiler!")
+endif()
+
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+    set(IS_GNU On)
+    add_definitions(-DIS_GCC=true)
+else()
+    set(IS_GNU Off)
+    add_definitions(-DIS_GCC=false)
+endif()
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
+    set(IS_CLANG On)
+    add_definitions(-DIS_CLANG=true)
+else()
+    set(IS_CLANG Off)
+    add_definitions(-DIS_CLANG=false)
+endif()
+
+if(MSVC)
+    add_definitions(-DIS_MSVC=true)
+    add_definitions(/WX)
+    add_definitions(/W4)
+    add_definitions(/wd4189)
+    add_definitions(/wd4100)
+    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
+    add_definitions(/wd4267)
+    add_definitions(/wd4505)
+
+    # Use sane and nice C++ for MSVC.
+    # This makes alternative tokens (not, and, ...) as actual keywords and
+    # enables more conformant C++ in general
+    add_definitions(/permissive-)
+
+    
+else()
+    add_definitions(-DIS_MSVC=false)
+    add_definitions(-Werror)
+    add_definitions(-Wall)
+    add_definitions(-Wextra)
+    add_definitions(-Wold-style-cast)
+    add_definitions(-Wno-unused-variable)
+    add_definitions(-Wno-unused-parameter)
+    add_definitions(-Wno-unused-value)
+    add_definitions(-Wno-cpp)
+
+    if(IS_CLANG)
+      add_definitions(-Wno-unused-private-field)
+      add_definitions(-Wno-unneeded-internal-declaration)
+      
+    else()
+      add_definitions(-fcoroutines) # required for GCC-10    
+      
+    endif()
+endif()
+
+add_executable(${EXEC_NAME} main.cpp)
+
diff --git a/06.13-bcdConstexpr/main.cpp b/06.14-bcdConstexpr/main.cpp
similarity index 100%
rename from 06.13-bcdConstexpr/main.cpp
rename to 06.14-bcdConstexpr/main.cpp
diff --git a/06.14-customOrdering0/CMakeLists.txt b/06.14-customOrdering0/CMakeLists.txt
deleted file mode 100644
index ed3d91e..0000000
--- a/06.14-customOrdering0/CMakeLists.txt
+++ /dev/null
@@ -1,90 +0,0 @@
-# Copyright (c) Andreas Fertig.
-# SPDX-License-Identifier: MIT
-
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
-
-set(CXX_STANDARD_REQUIRED ON)
-set(CMAKE_CXX_STANDARD 20)
-
-set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
-
-project(${EXEC_NAME} CXX)
-
-# build the filename
-get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
-
-function(check_compiler COMPILER version)
-    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
-        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
-            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
-        endif()
-
-        set(HAVE_COMPILER On PARENT_SCOPE)
-    endif()
-endfunction(check_compiler)
-
-check_compiler("GNU" 10.2)
-check_compiler("Clang" 12.0)
-check_compiler("MSVC" 19.28.29914.0)
-
-
-if(NOT HAVE_COMPILER)
-    message(ERROR "You are using an unsupported compiler!")
-endif()
-
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-    set(IS_GNU On)
-    add_definitions(-DIS_GCC=true)
-else()
-    set(IS_GNU Off)
-    add_definitions(-DIS_GCC=false)
-endif()
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
-    set(IS_CLANG On)
-    add_definitions(-DIS_CLANG=true)
-else()
-    set(IS_CLANG Off)
-    add_definitions(-DIS_CLANG=false)
-endif()
-
-if(MSVC)
-    add_definitions(-DIS_MSVC=true)
-    add_definitions(/WX)
-    add_definitions(/W4)
-    add_definitions(/wd4189)
-    add_definitions(/wd4100)
-    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
-    add_definitions(/wd4267)
-    add_definitions(/wd4505)
-
-    # Use sane and nice C++ for MSVC.
-    # This makes alternative tokens (not, and, ...) as actual keywords and
-    # enables more conformant C++ in general
-    add_definitions(/permissive-)
-
-    
-else()
-    add_definitions(-DIS_MSVC=false)
-    add_definitions(-Werror)
-    add_definitions(-Wall)
-    add_definitions(-Wextra)
-    add_definitions(-Wold-style-cast)
-    add_definitions(-Wno-unused-variable)
-    add_definitions(-Wno-unused-parameter)
-    add_definitions(-Wno-unused-value)
-    add_definitions(-Wno-cpp)
-
-    if(IS_CLANG)
-      add_definitions(-Wno-unused-private-field)
-      add_definitions(-Wno-unneeded-internal-declaration)
-      
-    else()
-      add_definitions(-fcoroutines) # required for GCC-10    
-      
-    endif()
-endif()
-
-add_executable(${EXEC_NAME} main.cpp)
-
diff --git a/06.15-customOrdering0/CMakeLists.txt b/06.15-customOrdering0/CMakeLists.txt
new file mode 100644
index 0000000..03d498a
--- /dev/null
+++ b/06.15-customOrdering0/CMakeLists.txt
@@ -0,0 +1,90 @@
+# Copyright (c) Andreas Fertig.
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
+
+set(CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_STANDARD 20)
+
+set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
+
+project(${EXEC_NAME} CXX)
+
+# build the filename
+get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
+
+function(check_compiler COMPILER version)
+    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
+        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
+            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
+        endif()
+
+        set(HAVE_COMPILER On PARENT_SCOPE)
+    endif()
+endfunction(check_compiler)
+
+check_compiler("GNU" 10.2)
+check_compiler("Clang" 12.0)
+check_compiler("MSVC" 19.28.29914.0)
+
+
+if(NOT HAVE_COMPILER)
+    message(ERROR "You are using an unsupported compiler!")
+endif()
+
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+    set(IS_GNU On)
+    add_definitions(-DIS_GCC=true)
+else()
+    set(IS_GNU Off)
+    add_definitions(-DIS_GCC=false)
+endif()
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
+    set(IS_CLANG On)
+    add_definitions(-DIS_CLANG=true)
+else()
+    set(IS_CLANG Off)
+    add_definitions(-DIS_CLANG=false)
+endif()
+
+if(MSVC)
+    add_definitions(-DIS_MSVC=true)
+    add_definitions(/WX)
+    add_definitions(/W4)
+    add_definitions(/wd4189)
+    add_definitions(/wd4100)
+    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
+    add_definitions(/wd4267)
+    add_definitions(/wd4505)
+
+    # Use sane and nice C++ for MSVC.
+    # This makes alternative tokens (not, and, ...) as actual keywords and
+    # enables more conformant C++ in general
+    add_definitions(/permissive-)
+
+    
+else()
+    add_definitions(-DIS_MSVC=false)
+    add_definitions(-Werror)
+    add_definitions(-Wall)
+    add_definitions(-Wextra)
+    add_definitions(-Wold-style-cast)
+    add_definitions(-Wno-unused-variable)
+    add_definitions(-Wno-unused-parameter)
+    add_definitions(-Wno-unused-value)
+    add_definitions(-Wno-cpp)
+
+    if(IS_CLANG)
+      add_definitions(-Wno-unused-private-field)
+      add_definitions(-Wno-unneeded-internal-declaration)
+      
+    else()
+      add_definitions(-fcoroutines) # required for GCC-10    
+      
+    endif()
+endif()
+
+add_executable(${EXEC_NAME} main.cpp)
+
diff --git a/06.14-customOrdering0/main.cpp b/06.15-customOrdering0/main.cpp
similarity index 80%
rename from 06.14-customOrdering0/main.cpp
rename to 06.15-customOrdering0/main.cpp
index f0d80a8..de594eb 100644
--- a/06.14-customOrdering0/main.cpp
+++ b/06.15-customOrdering0/main.cpp
@@ -2,10 +2,10 @@
 // SPDX-License-Identifier: MIT
 
 #include <compare>
+#include <cstdint>
 #include <cstdio>
 #include <string>
 
-#if not defined(__clang__)
 struct Address {
   std::string city;
   std::string street;
@@ -20,13 +20,4 @@ int main()
   Address a2{"Heidelberg", "Hauptstrasse", 22};
 
   printf("%d\n", a1 > a2);
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/06.15-customOrdering1/CMakeLists.txt b/06.15-customOrdering1/CMakeLists.txt
deleted file mode 100644
index ed3d91e..0000000
--- a/06.15-customOrdering1/CMakeLists.txt
+++ /dev/null
@@ -1,90 +0,0 @@
-# Copyright (c) Andreas Fertig.
-# SPDX-License-Identifier: MIT
-
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
-
-set(CXX_STANDARD_REQUIRED ON)
-set(CMAKE_CXX_STANDARD 20)
-
-set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
-
-project(${EXEC_NAME} CXX)
-
-# build the filename
-get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
-
-function(check_compiler COMPILER version)
-    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
-        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
-            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
-        endif()
-
-        set(HAVE_COMPILER On PARENT_SCOPE)
-    endif()
-endfunction(check_compiler)
-
-check_compiler("GNU" 10.2)
-check_compiler("Clang" 12.0)
-check_compiler("MSVC" 19.28.29914.0)
-
-
-if(NOT HAVE_COMPILER)
-    message(ERROR "You are using an unsupported compiler!")
-endif()
-
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-    set(IS_GNU On)
-    add_definitions(-DIS_GCC=true)
-else()
-    set(IS_GNU Off)
-    add_definitions(-DIS_GCC=false)
-endif()
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
-    set(IS_CLANG On)
-    add_definitions(-DIS_CLANG=true)
-else()
-    set(IS_CLANG Off)
-    add_definitions(-DIS_CLANG=false)
-endif()
-
-if(MSVC)
-    add_definitions(-DIS_MSVC=true)
-    add_definitions(/WX)
-    add_definitions(/W4)
-    add_definitions(/wd4189)
-    add_definitions(/wd4100)
-    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
-    add_definitions(/wd4267)
-    add_definitions(/wd4505)
-
-    # Use sane and nice C++ for MSVC.
-    # This makes alternative tokens (not, and, ...) as actual keywords and
-    # enables more conformant C++ in general
-    add_definitions(/permissive-)
-
-    
-else()
-    add_definitions(-DIS_MSVC=false)
-    add_definitions(-Werror)
-    add_definitions(-Wall)
-    add_definitions(-Wextra)
-    add_definitions(-Wold-style-cast)
-    add_definitions(-Wno-unused-variable)
-    add_definitions(-Wno-unused-parameter)
-    add_definitions(-Wno-unused-value)
-    add_definitions(-Wno-cpp)
-
-    if(IS_CLANG)
-      add_definitions(-Wno-unused-private-field)
-      add_definitions(-Wno-unneeded-internal-declaration)
-      
-    else()
-      add_definitions(-fcoroutines) # required for GCC-10    
-      
-    endif()
-endif()
-
-add_executable(${EXEC_NAME} main.cpp)
-
diff --git a/06.16-customOrdering1/CMakeLists.txt b/06.16-customOrdering1/CMakeLists.txt
new file mode 100644
index 0000000..03d498a
--- /dev/null
+++ b/06.16-customOrdering1/CMakeLists.txt
@@ -0,0 +1,90 @@
+# Copyright (c) Andreas Fertig.
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
+
+set(CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_STANDARD 20)
+
+set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
+
+project(${EXEC_NAME} CXX)
+
+# build the filename
+get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
+
+function(check_compiler COMPILER version)
+    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
+        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
+            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
+        endif()
+
+        set(HAVE_COMPILER On PARENT_SCOPE)
+    endif()
+endfunction(check_compiler)
+
+check_compiler("GNU" 10.2)
+check_compiler("Clang" 12.0)
+check_compiler("MSVC" 19.28.29914.0)
+
+
+if(NOT HAVE_COMPILER)
+    message(ERROR "You are using an unsupported compiler!")
+endif()
+
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+    set(IS_GNU On)
+    add_definitions(-DIS_GCC=true)
+else()
+    set(IS_GNU Off)
+    add_definitions(-DIS_GCC=false)
+endif()
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
+    set(IS_CLANG On)
+    add_definitions(-DIS_CLANG=true)
+else()
+    set(IS_CLANG Off)
+    add_definitions(-DIS_CLANG=false)
+endif()
+
+if(MSVC)
+    add_definitions(-DIS_MSVC=true)
+    add_definitions(/WX)
+    add_definitions(/W4)
+    add_definitions(/wd4189)
+    add_definitions(/wd4100)
+    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
+    add_definitions(/wd4267)
+    add_definitions(/wd4505)
+
+    # Use sane and nice C++ for MSVC.
+    # This makes alternative tokens (not, and, ...) as actual keywords and
+    # enables more conformant C++ in general
+    add_definitions(/permissive-)
+
+    
+else()
+    add_definitions(-DIS_MSVC=false)
+    add_definitions(-Werror)
+    add_definitions(-Wall)
+    add_definitions(-Wextra)
+    add_definitions(-Wold-style-cast)
+    add_definitions(-Wno-unused-variable)
+    add_definitions(-Wno-unused-parameter)
+    add_definitions(-Wno-unused-value)
+    add_definitions(-Wno-cpp)
+
+    if(IS_CLANG)
+      add_definitions(-Wno-unused-private-field)
+      add_definitions(-Wno-unneeded-internal-declaration)
+      
+    else()
+      add_definitions(-fcoroutines) # required for GCC-10    
+      
+    endif()
+endif()
+
+add_executable(${EXEC_NAME} main.cpp)
+
diff --git a/06.15-customOrdering1/main.cpp b/06.16-customOrdering1/main.cpp
similarity index 88%
rename from 06.15-customOrdering1/main.cpp
rename to 06.16-customOrdering1/main.cpp
index 612a1bf..4072237 100644
--- a/06.15-customOrdering1/main.cpp
+++ b/06.16-customOrdering1/main.cpp
@@ -2,10 +2,10 @@
 // SPDX-License-Identifier: MIT
 
 #include <compare>
+#include <cstdint>
 #include <cstdio>
 #include <string>
 
-#if not defined(__clang__)
 struct Address {
   std::string city;
   std::string street;
@@ -35,14 +35,4 @@ int main()
   Address a2{"Heidelberg", "Hauptstrasse", 22};
 
   printf("%d\n", a1 > a2);
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-  return 1;
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/06.16-spaceshipWithLegacyCode0/CMakeLists.txt b/06.16-spaceshipWithLegacyCode0/CMakeLists.txt
deleted file mode 100644
index ed3d91e..0000000
--- a/06.16-spaceshipWithLegacyCode0/CMakeLists.txt
+++ /dev/null
@@ -1,90 +0,0 @@
-# Copyright (c) Andreas Fertig.
-# SPDX-License-Identifier: MIT
-
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
-
-set(CXX_STANDARD_REQUIRED ON)
-set(CMAKE_CXX_STANDARD 20)
-
-set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
-
-project(${EXEC_NAME} CXX)
-
-# build the filename
-get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
-
-function(check_compiler COMPILER version)
-    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
-        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
-            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
-        endif()
-
-        set(HAVE_COMPILER On PARENT_SCOPE)
-    endif()
-endfunction(check_compiler)
-
-check_compiler("GNU" 10.2)
-check_compiler("Clang" 12.0)
-check_compiler("MSVC" 19.28.29914.0)
-
-
-if(NOT HAVE_COMPILER)
-    message(ERROR "You are using an unsupported compiler!")
-endif()
-
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-    set(IS_GNU On)
-    add_definitions(-DIS_GCC=true)
-else()
-    set(IS_GNU Off)
-    add_definitions(-DIS_GCC=false)
-endif()
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
-    set(IS_CLANG On)
-    add_definitions(-DIS_CLANG=true)
-else()
-    set(IS_CLANG Off)
-    add_definitions(-DIS_CLANG=false)
-endif()
-
-if(MSVC)
-    add_definitions(-DIS_MSVC=true)
-    add_definitions(/WX)
-    add_definitions(/W4)
-    add_definitions(/wd4189)
-    add_definitions(/wd4100)
-    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
-    add_definitions(/wd4267)
-    add_definitions(/wd4505)
-
-    # Use sane and nice C++ for MSVC.
-    # This makes alternative tokens (not, and, ...) as actual keywords and
-    # enables more conformant C++ in general
-    add_definitions(/permissive-)
-
-    
-else()
-    add_definitions(-DIS_MSVC=false)
-    add_definitions(-Werror)
-    add_definitions(-Wall)
-    add_definitions(-Wextra)
-    add_definitions(-Wold-style-cast)
-    add_definitions(-Wno-unused-variable)
-    add_definitions(-Wno-unused-parameter)
-    add_definitions(-Wno-unused-value)
-    add_definitions(-Wno-cpp)
-
-    if(IS_CLANG)
-      add_definitions(-Wno-unused-private-field)
-      add_definitions(-Wno-unneeded-internal-declaration)
-      
-    else()
-      add_definitions(-fcoroutines) # required for GCC-10    
-      
-    endif()
-endif()
-
-add_executable(${EXEC_NAME} main.cpp)
-
diff --git a/06.17-spaceshipWithLegacyCode0/CMakeLists.txt b/06.17-spaceshipWithLegacyCode0/CMakeLists.txt
new file mode 100644
index 0000000..03d498a
--- /dev/null
+++ b/06.17-spaceshipWithLegacyCode0/CMakeLists.txt
@@ -0,0 +1,90 @@
+# Copyright (c) Andreas Fertig.
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
+
+set(CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_STANDARD 20)
+
+set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
+
+project(${EXEC_NAME} CXX)
+
+# build the filename
+get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
+
+function(check_compiler COMPILER version)
+    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
+        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
+            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
+        endif()
+
+        set(HAVE_COMPILER On PARENT_SCOPE)
+    endif()
+endfunction(check_compiler)
+
+check_compiler("GNU" 10.2)
+check_compiler("Clang" 12.0)
+check_compiler("MSVC" 19.28.29914.0)
+
+
+if(NOT HAVE_COMPILER)
+    message(ERROR "You are using an unsupported compiler!")
+endif()
+
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+    set(IS_GNU On)
+    add_definitions(-DIS_GCC=true)
+else()
+    set(IS_GNU Off)
+    add_definitions(-DIS_GCC=false)
+endif()
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
+    set(IS_CLANG On)
+    add_definitions(-DIS_CLANG=true)
+else()
+    set(IS_CLANG Off)
+    add_definitions(-DIS_CLANG=false)
+endif()
+
+if(MSVC)
+    add_definitions(-DIS_MSVC=true)
+    add_definitions(/WX)
+    add_definitions(/W4)
+    add_definitions(/wd4189)
+    add_definitions(/wd4100)
+    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
+    add_definitions(/wd4267)
+    add_definitions(/wd4505)
+
+    # Use sane and nice C++ for MSVC.
+    # This makes alternative tokens (not, and, ...) as actual keywords and
+    # enables more conformant C++ in general
+    add_definitions(/permissive-)
+
+    
+else()
+    add_definitions(-DIS_MSVC=false)
+    add_definitions(-Werror)
+    add_definitions(-Wall)
+    add_definitions(-Wextra)
+    add_definitions(-Wold-style-cast)
+    add_definitions(-Wno-unused-variable)
+    add_definitions(-Wno-unused-parameter)
+    add_definitions(-Wno-unused-value)
+    add_definitions(-Wno-cpp)
+
+    if(IS_CLANG)
+      add_definitions(-Wno-unused-private-field)
+      add_definitions(-Wno-unneeded-internal-declaration)
+      
+    else()
+      add_definitions(-fcoroutines) # required for GCC-10    
+      
+    endif()
+endif()
+
+add_executable(${EXEC_NAME} main.cpp)
+
diff --git a/06.16-spaceshipWithLegacyCode0/main.cpp b/06.17-spaceshipWithLegacyCode0/main.cpp
similarity index 100%
rename from 06.16-spaceshipWithLegacyCode0/main.cpp
rename to 06.17-spaceshipWithLegacyCode0/main.cpp
diff --git a/06.17-see-06.16-spaceshipWithLegacyCode0 b/06.18-see-06.17-spaceshipWithLegacyCode0
similarity index 100%
rename from 06.17-see-06.16-spaceshipWithLegacyCode0
rename to 06.18-see-06.17-spaceshipWithLegacyCode0
diff --git a/06.18-spaceshipEqualityRewrite2/CMakeLists.txt b/06.18-spaceshipEqualityRewrite2/CMakeLists.txt
deleted file mode 100644
index ed3d91e..0000000
--- a/06.18-spaceshipEqualityRewrite2/CMakeLists.txt
+++ /dev/null
@@ -1,90 +0,0 @@
-# Copyright (c) Andreas Fertig.
-# SPDX-License-Identifier: MIT
-
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
-
-set(CXX_STANDARD_REQUIRED ON)
-set(CMAKE_CXX_STANDARD 20)
-
-set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
-
-project(${EXEC_NAME} CXX)
-
-# build the filename
-get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
-
-function(check_compiler COMPILER version)
-    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
-        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
-            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
-        endif()
-
-        set(HAVE_COMPILER On PARENT_SCOPE)
-    endif()
-endfunction(check_compiler)
-
-check_compiler("GNU" 10.2)
-check_compiler("Clang" 12.0)
-check_compiler("MSVC" 19.28.29914.0)
-
-
-if(NOT HAVE_COMPILER)
-    message(ERROR "You are using an unsupported compiler!")
-endif()
-
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-    set(IS_GNU On)
-    add_definitions(-DIS_GCC=true)
-else()
-    set(IS_GNU Off)
-    add_definitions(-DIS_GCC=false)
-endif()
-
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
-    set(IS_CLANG On)
-    add_definitions(-DIS_CLANG=true)
-else()
-    set(IS_CLANG Off)
-    add_definitions(-DIS_CLANG=false)
-endif()
-
-if(MSVC)
-    add_definitions(-DIS_MSVC=true)
-    add_definitions(/WX)
-    add_definitions(/W4)
-    add_definitions(/wd4189)
-    add_definitions(/wd4100)
-    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
-    add_definitions(/wd4267)
-    add_definitions(/wd4505)
-
-    # Use sane and nice C++ for MSVC.
-    # This makes alternative tokens (not, and, ...) as actual keywords and
-    # enables more conformant C++ in general
-    add_definitions(/permissive-)
-
-    
-else()
-    add_definitions(-DIS_MSVC=false)
-    add_definitions(-Werror)
-    add_definitions(-Wall)
-    add_definitions(-Wextra)
-    add_definitions(-Wold-style-cast)
-    add_definitions(-Wno-unused-variable)
-    add_definitions(-Wno-unused-parameter)
-    add_definitions(-Wno-unused-value)
-    add_definitions(-Wno-cpp)
-
-    if(IS_CLANG)
-      add_definitions(-Wno-unused-private-field)
-      add_definitions(-Wno-unneeded-internal-declaration)
-      
-    else()
-      add_definitions(-fcoroutines) # required for GCC-10    
-      
-    endif()
-endif()
-
-add_executable(${EXEC_NAME} main.cpp)
-
diff --git a/06.19-spaceshipEqualityRewrite2/CMakeLists.txt b/06.19-spaceshipEqualityRewrite2/CMakeLists.txt
new file mode 100644
index 0000000..03d498a
--- /dev/null
+++ b/06.19-spaceshipEqualityRewrite2/CMakeLists.txt
@@ -0,0 +1,90 @@
+# Copyright (c) Andreas Fertig.
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
+
+set(CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_STANDARD 20)
+
+set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
+
+project(${EXEC_NAME} CXX)
+
+# build the filename
+get_filename_component(EXEC_NAME "${EXEC_NAME}" NAME)
+
+function(check_compiler COMPILER version)
+    if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "${COMPILER}")
+        if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS ${version})
+            message(FATAL_ERROR "${COMPILER} version must be at least ${version}!")
+        endif()
+
+        set(HAVE_COMPILER On PARENT_SCOPE)
+    endif()
+endfunction(check_compiler)
+
+check_compiler("GNU" 10.2)
+check_compiler("Clang" 12.0)
+check_compiler("MSVC" 19.28.29914.0)
+
+
+if(NOT HAVE_COMPILER)
+    message(ERROR "You are using an unsupported compiler!")
+endif()
+
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+    set(IS_GNU On)
+    add_definitions(-DIS_GCC=true)
+else()
+    set(IS_GNU Off)
+    add_definitions(-DIS_GCC=false)
+endif()
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang")
+    set(IS_CLANG On)
+    add_definitions(-DIS_CLANG=true)
+else()
+    set(IS_CLANG Off)
+    add_definitions(-DIS_CLANG=false)
+endif()
+
+if(MSVC)
+    add_definitions(-DIS_MSVC=true)
+    add_definitions(/WX)
+    add_definitions(/W4)
+    add_definitions(/wd4189)
+    add_definitions(/wd4100)
+    add_definitions(/wd4996) # 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS.
+    add_definitions(/wd4267)
+    add_definitions(/wd4505)
+
+    # Use sane and nice C++ for MSVC.
+    # This makes alternative tokens (not, and, ...) as actual keywords and
+    # enables more conformant C++ in general
+    add_definitions(/permissive-)
+
+    
+else()
+    add_definitions(-DIS_MSVC=false)
+    add_definitions(-Werror)
+    add_definitions(-Wall)
+    add_definitions(-Wextra)
+    add_definitions(-Wold-style-cast)
+    add_definitions(-Wno-unused-variable)
+    add_definitions(-Wno-unused-parameter)
+    add_definitions(-Wno-unused-value)
+    add_definitions(-Wno-cpp)
+
+    if(IS_CLANG)
+      add_definitions(-Wno-unused-private-field)
+      add_definitions(-Wno-unneeded-internal-declaration)
+      
+    else()
+      add_definitions(-fcoroutines) # required for GCC-10    
+      
+    endif()
+endif()
+
+add_executable(${EXEC_NAME} main.cpp)
+
diff --git a/06.18-spaceshipEqualityRewrite2/main.cpp b/06.19-spaceshipEqualityRewrite2/main.cpp
similarity index 100%
rename from 06.18-spaceshipEqualityRewrite2/main.cpp
rename to 06.19-spaceshipEqualityRewrite2/main.cpp
diff --git a/07.01-captureByCopy0/CMakeLists.txt b/07.01-captureByCopy0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/07.01-captureByCopy0/CMakeLists.txt
+++ b/07.01-captureByCopy0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/07.02-captureByCopy1/CMakeLists.txt b/07.02-captureByCopy1/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/07.02-captureByCopy1/CMakeLists.txt
+++ b/07.02-captureByCopy1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/07.03-captureByCopy1Insights/CMakeLists.txt b/07.03-captureByCopy1Insights/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/07.03-captureByCopy1Insights/CMakeLists.txt
+++ b/07.03-captureByCopy1Insights/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/07.04-captureByCopy2/CMakeLists.txt b/07.04-captureByCopy2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.04-captureByCopy2/CMakeLists.txt
+++ b/07.04-captureByCopy2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.05-mapSortBooksByIsbn0/CMakeLists.txt b/07.05-mapSortBooksByIsbn0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/07.05-mapSortBooksByIsbn0/CMakeLists.txt
+++ b/07.05-mapSortBooksByIsbn0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/07.07-mapSortBooksByIsbn1/CMakeLists.txt b/07.07-mapSortBooksByIsbn1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.07-mapSortBooksByIsbn1/CMakeLists.txt
+++ b/07.07-mapSortBooksByIsbn1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.08-mapSortBooksByIsbn2/CMakeLists.txt b/07.08-mapSortBooksByIsbn2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.08-mapSortBooksByIsbn2/CMakeLists.txt
+++ b/07.08-mapSortBooksByIsbn2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.09-mapSortBooksByIsbn3/CMakeLists.txt b/07.09-mapSortBooksByIsbn3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.09-mapSortBooksByIsbn3/CMakeLists.txt
+++ b/07.09-mapSortBooksByIsbn3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.09-mapSortBooksByIsbn3/main.cpp b/07.09-mapSortBooksByIsbn3/main.cpp
index 787e533..34b638e 100644
--- a/07.09-mapSortBooksByIsbn3/main.cpp
+++ b/07.09-mapSortBooksByIsbn3/main.cpp
@@ -22,12 +22,11 @@ struct Price {
 
 #if(__cpp_generic_lambdas >= 201707)
 template<typename KEY, typename VALUE>
-using MapSortedByIsbn =
-  std::map<KEY,
-           VALUE,
-           decltype(
-             [](const auto& a,  // #A Using a generic lambda
-                const auto& b) { return a.isbn > b.isbn; })>;
+using MapSortedByIsbn = std::map<
+  KEY,
+  VALUE,
+  decltype([](const auto& a,  // #A Using a generic lambda
+              const auto& b) { return a.isbn > b.isbn; })>;
 
 namespace usingAliasVersion {
   // #A Define a using alias with the compare lambda which can
diff --git a/07.13-mapSortBooksByIsbn4/CMakeLists.txt b/07.13-mapSortBooksByIsbn4/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.13-mapSortBooksByIsbn4/CMakeLists.txt
+++ b/07.13-mapSortBooksByIsbn4/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.14-printWithOrigin0/CMakeLists.txt b/07.14-printWithOrigin0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/07.14-printWithOrigin0/CMakeLists.txt
+++ b/07.14-printWithOrigin0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/07.15-genericLambdaVarArgsForward0/CMakeLists.txt b/07.15-genericLambdaVarArgsForward0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/07.15-genericLambdaVarArgsForward0/CMakeLists.txt
+++ b/07.15-genericLambdaVarArgsForward0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/07.17-genericLambdaVarArgsForward1/CMakeLists.txt b/07.17-genericLambdaVarArgsForward1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.17-genericLambdaVarArgsForward1/CMakeLists.txt
+++ b/07.17-genericLambdaVarArgsForward1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.18-genericLambdaVarArgsForward2/CMakeLists.txt b/07.18-genericLambdaVarArgsForward2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.18-genericLambdaVarArgsForward2/CMakeLists.txt
+++ b/07.18-genericLambdaVarArgsForward2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.19-lambdaInitCapture0/CMakeLists.txt b/07.19-lambdaInitCapture0/CMakeLists.txt
index df94d21..5ce5e14 100644
--- a/07.19-lambdaInitCapture0/CMakeLists.txt
+++ b/07.19-lambdaInitCapture0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 14)
diff --git a/07.20-genericLambdaVarArgsForward3/CMakeLists.txt b/07.20-genericLambdaVarArgsForward3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.20-genericLambdaVarArgsForward3/CMakeLists.txt
+++ b/07.20-genericLambdaVarArgsForward3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.21-genericLambdaVarArgsForward4/CMakeLists.txt b/07.21-genericLambdaVarArgsForward4/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.21-genericLambdaVarArgsForward4/CMakeLists.txt
+++ b/07.21-genericLambdaVarArgsForward4/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.23-genericLambdaVarArgsForward5/CMakeLists.txt b/07.23-genericLambdaVarArgsForward5/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.23-genericLambdaVarArgsForward5/CMakeLists.txt
+++ b/07.23-genericLambdaVarArgsForward5/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.24-genericLambdaVarArgsForward6/CMakeLists.txt b/07.24-genericLambdaVarArgsForward6/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.24-genericLambdaVarArgsForward6/CMakeLists.txt
+++ b/07.24-genericLambdaVarArgsForward6/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.25-genericLambdaVarArgsForward7/CMakeLists.txt b/07.25-genericLambdaVarArgsForward7/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/07.25-genericLambdaVarArgsForward7/CMakeLists.txt
+++ b/07.25-genericLambdaVarArgsForward7/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/07.25-genericLambdaVarArgsForward7/main.cpp b/07.25-genericLambdaVarArgsForward7/main.cpp
index 350b38a..c0df4bd 100644
--- a/07.25-genericLambdaVarArgsForward7/main.cpp
+++ b/07.25-genericLambdaVarArgsForward7/main.cpp
@@ -28,8 +28,8 @@ auto getNamedLogger(Origins&&... origins)
 {
   return [... _origins = std::forward<Origins>(origins)]
     // #A Type-constraint NotFloatingPoint to restrict all parameters not to be floats
-    <NotFloatingPoint... Ts>(Ts && ... args) requires(
-      not std::disjunction_v<std::is_pointer<Origins>...>)
+    <NotFloatingPoint... Ts>(Ts && ... args)
+    requires(not std::disjunction_v<std::is_pointer<Origins>...>)
   {
     print(_origins..., std::forward<Ts>(args)...);
   };
diff --git a/08.01-aggregateInit0/CMakeLists.txt b/08.01-aggregateInit0/CMakeLists.txt
index 14b1ad9..2811d7c 100644
--- a/08.01-aggregateInit0/CMakeLists.txt
+++ b/08.01-aggregateInit0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 14)
diff --git a/08.02-userProvidedVsDeclared0/CMakeLists.txt b/08.02-userProvidedVsDeclared0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/08.02-userProvidedVsDeclared0/CMakeLists.txt
+++ b/08.02-userProvidedVsDeclared0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.03-designatedInitializers0/CMakeLists.txt b/08.03-designatedInitializers0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.03-designatedInitializers0/CMakeLists.txt
+++ b/08.03-designatedInitializers0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.04-designatedInitializers1/CMakeLists.txt b/08.04-designatedInitializers1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/08.04-designatedInitializers1/CMakeLists.txt
+++ b/08.04-designatedInitializers1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.05-mostVertexingParse0/CMakeLists.txt b/08.05-mostVertexingParse0/CMakeLists.txt
index 6b6ab12..a5a3beb 100644
--- a/08.05-mostVertexingParse0/CMakeLists.txt
+++ b/08.05-mostVertexingParse0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.06-designatedInitializers2/CMakeLists.txt b/08.06-designatedInitializers2/CMakeLists.txt
index 134ea0d..39b115d 100644
--- a/08.06-designatedInitializers2/CMakeLists.txt
+++ b/08.06-designatedInitializers2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.07-designatedInitializers3/CMakeLists.txt b/08.07-designatedInitializers3/CMakeLists.txt
index d1c753e..bd9f88f 100644
--- a/08.07-designatedInitializers3/CMakeLists.txt
+++ b/08.07-designatedInitializers3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.09-designatedInitializers4/CMakeLists.txt b/08.09-designatedInitializers4/CMakeLists.txt
index a23742e..22f0d81 100644
--- a/08.09-designatedInitializers4/CMakeLists.txt
+++ b/08.09-designatedInitializers4/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.10-guaranteedCopyElision0/CMakeLists.txt b/08.10-guaranteedCopyElision0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.10-guaranteedCopyElision0/CMakeLists.txt
+++ b/08.10-guaranteedCopyElision0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.11-designatedInitializers5/CMakeLists.txt b/08.11-designatedInitializers5/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/08.11-designatedInitializers5/CMakeLists.txt
+++ b/08.11-designatedInitializers5/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.13-designatedInitializersAndFunctionParameters0/CMakeLists.txt b/08.13-designatedInitializersAndFunctionParameters0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.13-designatedInitializersAndFunctionParameters0/CMakeLists.txt
+++ b/08.13-designatedInitializersAndFunctionParameters0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.15-designatedInitializersAndFunctionParameters1/CMakeLists.txt b/08.15-designatedInitializersAndFunctionParameters1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/08.15-designatedInitializersAndFunctionParameters1/CMakeLists.txt
+++ b/08.15-designatedInitializersAndFunctionParameters1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.17-designatedInitializersOverloadResolution0/CMakeLists.txt b/08.17-designatedInitializersOverloadResolution0/CMakeLists.txt
index a23742e..22f0d81 100644
--- a/08.17-designatedInitializersOverloadResolution0/CMakeLists.txt
+++ b/08.17-designatedInitializersOverloadResolution0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.17-designatedInitializersOverloadResolution0/main.cpp b/08.17-designatedInitializersOverloadResolution0/main.cpp
index b3910a3..598ea60 100644
--- a/08.17-designatedInitializersOverloadResolution0/main.cpp
+++ b/08.17-designatedInitializersOverloadResolution0/main.cpp
@@ -20,12 +20,12 @@ void Add(const Point2D& p, int v);
 
 void Add(const Point& p, int v)
 {
-  printf("Point\n");
+  puts("Point");
 }
 
 void Add(const Point2D& p, int v)
 {
-  printf("Point2D\n");
+  puts("Point2D");
 }
 
 int main()
diff --git a/08.18-bracedInitVsParensWithStdVector0/CMakeLists.txt b/08.18-bracedInitVsParensWithStdVector0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.18-bracedInitVsParensWithStdVector0/CMakeLists.txt
+++ b/08.18-bracedInitVsParensWithStdVector0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.19-makeUniqueWithAnAggregate0/CMakeLists.txt b/08.19-makeUniqueWithAnAggregate0/CMakeLists.txt
index 796c1c2..d7a7550 100644
--- a/08.19-makeUniqueWithAnAggregate0/CMakeLists.txt
+++ b/08.19-makeUniqueWithAnAggregate0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.21-initializationForms0/CMakeLists.txt b/08.21-initializationForms0/CMakeLists.txt
index 1dc0d59..daf86f8 100644
--- a/08.21-initializationForms0/CMakeLists.txt
+++ b/08.21-initializationForms0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/08.21-initializationForms0/main.cpp b/08.21-initializationForms0/main.cpp
index 2c4400b..9da6d9a 100644
--- a/08.21-initializationForms0/main.cpp
+++ b/08.21-initializationForms0/main.cpp
@@ -41,8 +41,8 @@ int main()
   // Point bNarrowing{3.5};// #J Does not allow narrowing
   Point pNarrowing(3.5);  // #K Allows narrowing
 
-  Point bValueInit{};  // #L Default or zero initialization
-  Point pValueInit();  // #M Still a function declaration
+  Point bValueInit{};     // #L Default or zero initialization
+  Point pValueInit();     // #M Still a function declaration
 
   // #N Initialization of a built-in type
   int bBuiltIn{4};
diff --git a/08.22-aggregateWithUserDeclaredConstructor0/CMakeLists.txt b/08.22-aggregateWithUserDeclaredConstructor0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.22-aggregateWithUserDeclaredConstructor0/CMakeLists.txt
+++ b/08.22-aggregateWithUserDeclaredConstructor0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.25-ctad0/CMakeLists.txt b/08.25-ctad0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.25-ctad0/CMakeLists.txt
+++ b/08.25-ctad0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.26-structuredBindingsPOSIXError0/CMakeLists.txt b/08.26-structuredBindingsPOSIXError0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.26-structuredBindingsPOSIXError0/CMakeLists.txt
+++ b/08.26-structuredBindingsPOSIXError0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.27-structuredBindingsPOSIXError1/CMakeLists.txt b/08.27-structuredBindingsPOSIXError1/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.27-structuredBindingsPOSIXError1/CMakeLists.txt
+++ b/08.27-structuredBindingsPOSIXError1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.28-structuredBindingsPOSIXError2/CMakeLists.txt b/08.28-structuredBindingsPOSIXError2/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.28-structuredBindingsPOSIXError2/CMakeLists.txt
+++ b/08.28-structuredBindingsPOSIXError2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.29-structuredBindingsPOSIXError3/CMakeLists.txt b/08.29-structuredBindingsPOSIXError3/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/08.29-structuredBindingsPOSIXError3/CMakeLists.txt
+++ b/08.29-structuredBindingsPOSIXError3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/08.30-structuredBindingsPOSIXError4/CMakeLists.txt b/08.30-structuredBindingsPOSIXError4/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/08.30-structuredBindingsPOSIXError4/CMakeLists.txt
+++ b/08.30-structuredBindingsPOSIXError4/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/09.01-stdArray0/CMakeLists.txt b/09.01-stdArray0/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/09.01-stdArray0/CMakeLists.txt
+++ b/09.01-stdArray0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/09.02-floatingPointNTTP0/CMakeLists.txt b/09.02-floatingPointNTTP0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/09.02-floatingPointNTTP0/CMakeLists.txt
+++ b/09.02-floatingPointNTTP0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/09.03-fixedString0/CMakeLists.txt b/09.03-fixedString0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/09.03-fixedString0/CMakeLists.txt
+++ b/09.03-fixedString0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/09.04-fixedString1/CMakeLists.txt b/09.04-fixedString1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/09.04-fixedString1/CMakeLists.txt
+++ b/09.04-fixedString1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/09.04-fixedString1/main.cpp b/09.04-fixedString1/main.cpp
index ab92d3c..01a542f 100644
--- a/09.04-fixedString1/main.cpp
+++ b/09.04-fixedString1/main.cpp
@@ -6,7 +6,6 @@
 #include <iostream>
 #include <version>
 
-#if not defined(__clang__)
 template<typename CharT, std::size_t N>
 struct fixed_string {
   CharT data[N]{};
@@ -61,10 +60,4 @@ int main()
   FixedStringContainer<"Hello, C++"> fc{};
   fc.print();  // #D For those who believe it only if they see
                // it
-}
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/09.12-fixedString2/CMakeLists.txt b/09.12-fixedString2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/09.12-fixedString2/CMakeLists.txt
+++ b/09.12-fixedString2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/09.12-fixedString2/main.cpp b/09.12-fixedString2/main.cpp
index 0ed0bb6..cd09487 100644
--- a/09.12-fixedString2/main.cpp
+++ b/09.12-fixedString2/main.cpp
@@ -7,7 +7,6 @@
 #include <cstddef>
 #include <iostream>
 
-#if __has_include(<ranges>) and not defined(__clang__)
 template<typename CharT, std::size_t N>
 struct fixed_string {
   CharT data[N]{};
@@ -52,10 +51,4 @@ int main()
   print(FormatString<"%s, %s">{}, "Hello", "C++20");
 
   print("%s, %s"_fs, "Hello", "C++20");
-}
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/09.13-fixedString3/CMakeLists.txt b/09.13-fixedString3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/09.13-fixedString3/CMakeLists.txt
+++ b/09.13-fixedString3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/09.13-fixedString3/main.cpp b/09.13-fixedString3/main.cpp
index 500756e..c635c91 100644
--- a/09.13-fixedString3/main.cpp
+++ b/09.13-fixedString3/main.cpp
@@ -5,10 +5,9 @@
 
 #include <algorithm>
 #include <cstddef>
+#include <cstdio>
 #include <span>
 
-#if __has_include(<ranges>) and not defined(__clang__)
-
 template<typename CharT, std::size_t N>
 struct fixed_string {
   CharT data[N]{};
@@ -80,11 +79,9 @@ constexpr auto get(const std::span<const CharT>& str)
 template<typename CharT, typename... Ts>
 constexpr bool IsMatching(std::span<const CharT> str)
 {
-  return [&]<size_t... I>(std::index_sequence<I...>)
-  {
+  return [&]<size_t... I>(std::index_sequence<I...>) {
     return ((match<Ts>(get<I>(str))) && ...);
-  }
-  (std::make_index_sequence<sizeof...(Ts)>{});
+  }(std::make_index_sequence<sizeof...(Ts)>{});
 }
 
 template<typename... Args>
@@ -127,12 +124,4 @@ int main()
 
   char fmt[]{"Hello, %s"};
   print(fmt, "C++20");
-
-  // fmt("test");
-}
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/10.01-bitCastFloatToInt0/CMakeLists.txt b/10.01-bitCastFloatToInt0/CMakeLists.txt
index a5353cc..b228ac0 100644
--- a/10.01-bitCastFloatToInt0/CMakeLists.txt
+++ b/10.01-bitCastFloatToInt0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/10.02-bitCastFloatToInt1/CMakeLists.txt b/10.02-bitCastFloatToInt1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.02-bitCastFloatToInt1/CMakeLists.txt
+++ b/10.02-bitCastFloatToInt1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.03-byteSwap0/CMakeLists.txt b/10.03-byteSwap0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.03-byteSwap0/CMakeLists.txt
+++ b/10.03-byteSwap0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.03-byteSwap0/main.cpp b/10.03-byteSwap0/main.cpp
index e13264b..bb7fbd7 100644
--- a/10.03-byteSwap0/main.cpp
+++ b/10.03-byteSwap0/main.cpp
@@ -11,13 +11,11 @@
 
 constexpr auto ReverseBytes(std::integral auto value)
 {
-  return [&]<size_t... I>(std::index_sequence<I...>)->decltype(value)
-  {
+  return [&]<size_t... I>(std::index_sequence<I...>) -> decltype(value) {
     return (
       (((value >> I * 8) & 0xff) << ((8 * sizeof(value)) - ((1 + I) * 8))) |
       ...);
-  }
-  (std::make_index_sequence<sizeof(value)>{});
+  }(std::make_index_sequence<sizeof(value)>{});
 }
 
 constexpr auto ByteSwap(std::integral auto value)
diff --git a/10.04-stdArrayVsCArray0/CMakeLists.txt b/10.04-stdArrayVsCArray0/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/10.04-stdArrayVsCArray0/CMakeLists.txt
+++ b/10.04-stdArrayVsCArray0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/10.05-stdArrayVsCArray1/CMakeLists.txt b/10.05-stdArrayVsCArray1/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/10.05-stdArrayVsCArray1/CMakeLists.txt
+++ b/10.05-stdArrayVsCArray1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/10.06-stdArrayVsCArray2/CMakeLists.txt b/10.06-stdArrayVsCArray2/CMakeLists.txt
index d1c753e..bd9f88f 100644
--- a/10.06-stdArrayVsCArray2/CMakeLists.txt
+++ b/10.06-stdArrayVsCArray2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.07-lengthAndValue0/CMakeLists.txt b/10.07-lengthAndValue0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/10.07-lengthAndValue0/CMakeLists.txt
+++ b/10.07-lengthAndValue0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/10.08-lengthAndValue1/CMakeLists.txt b/10.08-lengthAndValue1/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/10.08-lengthAndValue1/CMakeLists.txt
+++ b/10.08-lengthAndValue1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/10.09-lengthAndValue2/CMakeLists.txt b/10.09-lengthAndValue2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.09-lengthAndValue2/CMakeLists.txt
+++ b/10.09-lengthAndValue2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.10-span0/CMakeLists.txt b/10.10-span0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.10-span0/CMakeLists.txt
+++ b/10.10-span0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.11-assert0/CMakeLists.txt b/10.11-assert0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/10.11-assert0/CMakeLists.txt
+++ b/10.11-assert0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/10.13-assert1/CMakeLists.txt b/10.13-assert1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.13-assert1/CMakeLists.txt
+++ b/10.13-assert1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.13-assert1/main.cpp b/10.13-assert1/main.cpp
index 68ad5be..8e8ccc4 100644
--- a/10.13-assert1/main.cpp
+++ b/10.13-assert1/main.cpp
@@ -1,10 +1,9 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<source_location>) && not defined(__clang__)
-#  include <iostream>
-#  include <source_location>
-#  include <string_view>
+#include <iostream>
+#include <source_location>
+#include <string_view>
 
 // #A Assert function taking condition, message, and source
 // location
@@ -24,10 +23,4 @@ int main()
 {
   // #C A call to Assert with  information of Use
   Assert(1 != 2, "Not met");
-}
-#else
-int main()
-{
-#  pragma message("not supported")
-}
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/10.14-logFunction0/CMakeLists.txt b/10.14-logFunction0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.14-logFunction0/CMakeLists.txt
+++ b/10.14-logFunction0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.14-logFunction0/main.cpp b/10.14-logFunction0/main.cpp
index 407235e..9f0b892 100644
--- a/10.14-logFunction0/main.cpp
+++ b/10.14-logFunction0/main.cpp
@@ -1,10 +1,9 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__)
-#  include <format>
-#  include <iostream>
-#  include <string_view>
+#include <format>
+#include <iostream>
+#include <string_view>
 
 enum LogLevel { Info, Warning, Error };
 
@@ -24,19 +23,10 @@ void Log(LogLevel         level,
 }
 
 // #B Macro wrapper to call Log
-#  define LOG(level, fmt, ...)                                 \
-    Log(level, __FUNCTION__, __LINE__, fmt, __VA_ARGS__)
+#define LOG(level, fmt, ...)                                   \
+  Log(level, __FUNCTION__, __LINE__, fmt, __VA_ARGS__)
 
 int main()
 {
   LOG(LogLevel::Info, "hello {} {} {}", 2, 3, 4);
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/10.15-logFunction1/CMakeLists.txt b/10.15-logFunction1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.15-logFunction1/CMakeLists.txt
+++ b/10.15-logFunction1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.15-logFunction1/main.cpp b/10.15-logFunction1/main.cpp
index ffabae6..52929c4 100644
--- a/10.15-logFunction1/main.cpp
+++ b/10.15-logFunction1/main.cpp
@@ -1,11 +1,10 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(<format>) and not defined(__clang__) && __has_include(<source_location>)
-#  include <format>
-#  include <iostream>
-#  include <source_location>
-#  include <string_view>
+#include <format>
+#include <iostream>
+#include <source_location>
+#include <string_view>
 
 enum LogLevel { Info, Warning, Error };
 
@@ -24,22 +23,10 @@ void Log(LogLevel             level,
 }
 
 // #B Macro wrapper to call Log
-#  define LOG(level, fmt, ...)                                 \
-    Log(level,                                                 \
-        std::source_location::current(),                       \
-        fmt,                                                   \
-        __VA_ARGS__)
+#define LOG(level, fmt, ...)                                   \
+  Log(level, std::source_location::current(), fmt, __VA_ARGS__)
 
 int main()
 {
   LOG(LogLevel::Info, "hello {} {} {}", 2, 3, 4);
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/10.16-logFunction2/CMakeLists.txt b/10.16-logFunction2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.16-logFunction2/CMakeLists.txt
+++ b/10.16-logFunction2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.16-logFunction2/main.cpp b/10.16-logFunction2/main.cpp
index 3b65de7..0729741 100644
--- a/10.16-logFunction2/main.cpp
+++ b/10.16-logFunction2/main.cpp
@@ -1,12 +1,10 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#if __has_include(                                             \
-  <format>) and not defined(__clang__) && __has_include(<source_location>) && not defined(__clang__)
-#  include <format>
-#  include <iostream>
-#  include <source_location>
-#  include <string_view>
+#include <format>
+#include <iostream>
+#include <source_location>
+#include <string_view>
 
 enum LogLevel { Info, Warning, Error };
 
@@ -39,13 +37,4 @@ void Log(LogLevel level, Format fmt, const auto&... args)
 int main()
 {
   Log(LogLevel::Info, "hello {} {} {}", 2, 3, 4);
-}
-
-#else
-
-int main()
-{
-#  pragma message("not supported")
-}
-
-#endif
\ No newline at end of file
+}
\ No newline at end of file
diff --git a/10.17-mapContains0/CMakeLists.txt b/10.17-mapContains0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/10.17-mapContains0/CMakeLists.txt
+++ b/10.17-mapContains0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/10.18-mapContains1/CMakeLists.txt b/10.18-mapContains1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.18-mapContains1/CMakeLists.txt
+++ b/10.18-mapContains1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.19-startsWith0/CMakeLists.txt b/10.19-startsWith0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/10.19-startsWith0/CMakeLists.txt
+++ b/10.19-startsWith0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/10.19-startsWith0/main.cpp b/10.19-startsWith0/main.cpp
index c6fcc50..764ed2e 100644
--- a/10.19-startsWith0/main.cpp
+++ b/10.19-startsWith0/main.cpp
@@ -7,5 +7,5 @@ int main()
 {
   const std::string s{"Hello, C++20"};
 
-  if(s.find("Hello") != std::string::npos) { printf("Found!\n"); }
+  if(s.find("Hello") != std::string::npos) { puts("Found!"); }
 }
\ No newline at end of file
diff --git a/10.20-startsWith1/CMakeLists.txt b/10.20-startsWith1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/10.20-startsWith1/CMakeLists.txt
+++ b/10.20-startsWith1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/10.20-startsWith1/main.cpp b/10.20-startsWith1/main.cpp
index ac4e9db..5906484 100644
--- a/10.20-startsWith1/main.cpp
+++ b/10.20-startsWith1/main.cpp
@@ -7,7 +7,7 @@ int main()
 {
   const std::string s{"Hello, C++20"};
 
-  if(s.starts_with("Hello")) { printf("Found!\n"); }
+  if(s.starts_with("Hello")) { puts("Found!"); }
 
-  if(s.ends_with("C++20")) { printf("Found!\n"); }
+  if(s.ends_with("C++20")) { puts("Found!"); }
 }
\ No newline at end of file
diff --git a/11.01-rangeBaseForWithInit0/CMakeLists.txt b/11.01-rangeBaseForWithInit0/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/11.01-rangeBaseForWithInit0/CMakeLists.txt
+++ b/11.01-rangeBaseForWithInit0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/11.02-rangeBaseForWithInit1/CMakeLists.txt b/11.02-rangeBaseForWithInit1/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/11.02-rangeBaseForWithInit1/CMakeLists.txt
+++ b/11.02-rangeBaseForWithInit1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/11.03-rangeBaseForWithInit2/CMakeLists.txt b/11.03-rangeBaseForWithInit2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/11.03-rangeBaseForWithInit2/CMakeLists.txt
+++ b/11.03-rangeBaseForWithInit2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/11.04-rangeBasedForLoopWithTemporary0/CMakeLists.txt b/11.04-rangeBasedForLoopWithTemporary0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/11.04-rangeBasedForLoopWithTemporary0/CMakeLists.txt
+++ b/11.04-rangeBasedForLoopWithTemporary0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/11.04-rangeBasedForLoopWithTemporary0/main.cpp b/11.04-rangeBasedForLoopWithTemporary0/main.cpp
index 4dcf77e..1afb4ba 100644
--- a/11.04-rangeBasedForLoopWithTemporary0/main.cpp
+++ b/11.04-rangeBasedForLoopWithTemporary0/main.cpp
@@ -1,8 +1,9 @@
 // Copyright (c) Andreas Fertig.
 // SPDX-License-Identifier: MIT
 
-#include <iostream>
-#include <vector>
+#if not(defined(__GNUC__) && !defined(__clang__))
+#  include <iostream>
+#  include <vector>
 
 class Keeper {  // #A
   std::vector<int> data{2, 3, 4};
@@ -25,4 +26,10 @@ int main()
   for(auto& item : GetKeeper().items()) {
     std::cout << item << '\n';
   }
-}
\ No newline at end of file
+}
+#else
+int main()
+{
+#  pragma message("GCC detects the error")
+}
+#endif
\ No newline at end of file
diff --git a/11.05-rangeBasedForLoopWithTemporary1/CMakeLists.txt b/11.05-rangeBasedForLoopWithTemporary1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/11.05-rangeBasedForLoopWithTemporary1/CMakeLists.txt
+++ b/11.05-rangeBasedForLoopWithTemporary1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/11.06-likely0/CMakeLists.txt b/11.06-likely0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/11.06-likely0/CMakeLists.txt
+++ b/11.06-likely0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/11.06-likely0/main.cpp b/11.06-likely0/main.cpp
index a1dcd28..e6773ee 100644
--- a/11.06-likely0/main.cpp
+++ b/11.06-likely0/main.cpp
@@ -6,8 +6,8 @@
 int main(int value, const char*[])
 {
   switch(value) {
-    case 0: printf("Hello\n"); break;
-    case 1: printf("World\n"); break;
-    case 2: printf("C++\n"); break;
+    case 0: puts("Hello"); break;
+    case 1: puts("World"); break;
+    case 2: puts("C++"); break;
   }
 }
\ No newline at end of file
diff --git a/11.07-likely1/CMakeLists.txt b/11.07-likely1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/11.07-likely1/CMakeLists.txt
+++ b/11.07-likely1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/11.07-likely1/main.cpp b/11.07-likely1/main.cpp
index 4a1a027..933d232 100644
--- a/11.07-likely1/main.cpp
+++ b/11.07-likely1/main.cpp
@@ -6,9 +6,9 @@
 int main(int value, const char*[])
 {
 switch(value) {
-             case 0: printf("Hello\n"); break;
-  [[likely]] case 1: printf("World\n"); break;
-             case 2: printf("C++\n"); break;
+             case 0: puts("Hello"); break;
+  [[likely]] case 1: puts("World"); break;
+             case 2: puts("C++"); break;
 }
 
 }
\ No newline at end of file
diff --git a/11.08-notCopyable0/CMakeLists.txt b/11.08-notCopyable0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/11.08-notCopyable0/CMakeLists.txt
+++ b/11.08-notCopyable0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/11.09-notCopyable1/CMakeLists.txt b/11.09-notCopyable1/CMakeLists.txt
index 4d5f8f8..fb7aa9d 100644
--- a/11.09-notCopyable1/CMakeLists.txt
+++ b/11.09-notCopyable1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/11.10-usingEnum0/CMakeLists.txt b/11.10-usingEnum0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/11.10-usingEnum0/CMakeLists.txt
+++ b/11.10-usingEnum0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/11.11-usingEnum1/CMakeLists.txt b/11.11-usingEnum1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/11.11-usingEnum1/CMakeLists.txt
+++ b/11.11-usingEnum1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/11.12-conditionalExplicit0/CMakeLists.txt b/11.12-conditionalExplicit0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/11.12-conditionalExplicit0/CMakeLists.txt
+++ b/11.12-conditionalExplicit0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/11.13-conditionalExplicit1/CMakeLists.txt b/11.13-conditionalExplicit1/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/11.13-conditionalExplicit1/CMakeLists.txt
+++ b/11.13-conditionalExplicit1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/11.14-conditionalExplicit2/CMakeLists.txt b/11.14-conditionalExplicit2/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/11.14-conditionalExplicit2/CMakeLists.txt
+++ b/11.14-conditionalExplicit2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/11.15-conditionalExplicit5/CMakeLists.txt b/11.15-conditionalExplicit5/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/11.15-conditionalExplicit5/CMakeLists.txt
+++ b/11.15-conditionalExplicit5/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/12.01-constexprStrlenCpp110/CMakeLists.txt b/12.01-constexprStrlenCpp110/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/12.01-constexprStrlenCpp110/CMakeLists.txt
+++ b/12.01-constexprStrlenCpp110/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/12.02-constexprStrlenCpp111/CMakeLists.txt b/12.02-constexprStrlenCpp111/CMakeLists.txt
index 9566747..47b1d42 100644
--- a/12.02-constexprStrlenCpp111/CMakeLists.txt
+++ b/12.02-constexprStrlenCpp111/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 11)
diff --git a/12.03-constexprPoint0/CMakeLists.txt b/12.03-constexprPoint0/CMakeLists.txt
index 14b1ad9..2811d7c 100644
--- a/12.03-constexprPoint0/CMakeLists.txt
+++ b/12.03-constexprPoint0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 14)
diff --git a/12.04-constexprThrow0/CMakeLists.txt b/12.04-constexprThrow0/CMakeLists.txt
index 14b1ad9..2811d7c 100644
--- a/12.04-constexprThrow0/CMakeLists.txt
+++ b/12.04-constexprThrow0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 14)
diff --git a/12.05-throwAtCompileTime0/CMakeLists.txt b/12.05-throwAtCompileTime0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/12.05-throwAtCompileTime0/CMakeLists.txt
+++ b/12.05-throwAtCompileTime0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/12.06-logStatementInConstexpr0/CMakeLists.txt b/12.06-logStatementInConstexpr0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/12.06-logStatementInConstexpr0/CMakeLists.txt
+++ b/12.06-logStatementInConstexpr0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/12.08-byteSwap1/CMakeLists.txt b/12.08-byteSwap1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/12.08-byteSwap1/CMakeLists.txt
+++ b/12.08-byteSwap1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/12.08-byteSwap1/main.cpp b/12.08-byteSwap1/main.cpp
index fd84cc6..8db82ed 100644
--- a/12.08-byteSwap1/main.cpp
+++ b/12.08-byteSwap1/main.cpp
@@ -18,13 +18,12 @@
 
 constexpr auto ReverseBytes(std::integral auto value)
 {
-  return [&]<size_t... I>(std::index_sequence<I...>)->decltype(value)
-  {
-    return ((((value >> I * 8) & 0xff)
-             << ((8 * sizeof(value)) - ((1 + I) * 8))) |
-            ...);
-  }
-  (std::make_index_sequence<sizeof(value)>{});
+  return
+    [&]<size_t... I>(std::index_sequence<I...>) -> decltype(value) {
+      return ((((value >> I * 8) & 0xff)
+               << ((8 * sizeof(value)) - ((1 + I) * 8))) |
+              ...);
+    }(std::make_index_sequence<sizeof(value)>{});
 }
 
 template<std::integral T>
diff --git a/12.09-constantEvalutedAndConstexprIf0/CMakeLists.txt b/12.09-constantEvalutedAndConstexprIf0/CMakeLists.txt
index 2d1f52d..b54edd9 100644
--- a/12.09-constantEvalutedAndConstexprIf0/CMakeLists.txt
+++ b/12.09-constantEvalutedAndConstexprIf0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
@@ -84,7 +84,8 @@ else()
 
     else()
       add_definitions(-fcoroutines) # required for GCC-10    
-      
+      add_definitions(-Wno-tautological-compare)
+
     endif()
 endif()
 
diff --git a/12.10-constexprAllocation0/CMakeLists.txt b/12.10-constexprAllocation0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/12.10-constexprAllocation0/CMakeLists.txt
+++ b/12.10-constexprAllocation0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/12.12-constexprAllocation1/CMakeLists.txt b/12.12-constexprAllocation1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/12.12-constexprAllocation1/CMakeLists.txt
+++ b/12.12-constexprAllocation1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/12.14-constexprAllocation2/CMakeLists.txt b/12.14-constexprAllocation2/CMakeLists.txt
index ed3d91e..fb85410 100644
--- a/12.14-constexprAllocation2/CMakeLists.txt
+++ b/12.14-constexprAllocation2/CMakeLists.txt
@@ -1,10 +1,10 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
-set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD 23)
 
 set(EXEC_NAME ${CMAKE_CURRENT_SOURCE_DIR})
 
diff --git a/12.14-constexprAllocation2/main.cpp b/12.14-constexprAllocation2/main.cpp
index 5151cde..93573fb 100644
--- a/12.14-constexprAllocation2/main.cpp
+++ b/12.14-constexprAllocation2/main.cpp
@@ -3,19 +3,7 @@
 
 #if not(defined(__GNUC__) && !defined(__clang__))
 
-template<typename T>
-class unique_ptr {
-public:
-  constexpr unique_ptr(T* data) noexcept
-  : _data{data}
-  {}
-  constexpr ~unique_ptr() noexcept { delete _data; }
-
-  constexpr T* operator->() const noexcept { return _data; }
-
-private:
-  T* _data{};
-};
+#  include <memory>
 
 struct Car {  // #A Base class for all cars
   virtual ~Car()                      = default;
@@ -33,12 +21,12 @@ struct Tesla : Car {
   constexpr int speed() const override { return 9; }
 };
 
-constexpr unique_ptr<Car> CreateCar(int i)
+constexpr std::unique_ptr<Car> CreateCar(int i)
 {
   switch(i) {
-    case 0: return new Mercedes{};
-    case 1: return new Toyota{};
-    case 2: return new Tesla{};
+    case 0: return std::make_unique<Mercedes>();
+    case 1: return std::make_unique<Toyota>();
+    case 2: return std::make_unique<Tesla>();
   }
 
   return nullptr;
diff --git a/12.15-asConstant0/CMakeLists.txt b/12.15-asConstant0/CMakeLists.txt
index 114d0a0..09feead 100644
--- a/12.15-asConstant0/CMakeLists.txt
+++ b/12.15-asConstant0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
@@ -79,7 +79,8 @@ else()
     if(IS_CLANG)
       add_definitions(-Wno-unused-private-field)
       add_definitions(-Wno-unneeded-internal-declaration)
-      
+      add_definitions(-Wno-unused-but-set-variable)
+
     else()
       add_definitions(-fcoroutines) # required for GCC-10    
       
diff --git a/12.16-asConstant1/CMakeLists.txt b/12.16-asConstant1/CMakeLists.txt
index ed3d91e..fc89c11 100644
--- a/12.16-asConstant1/CMakeLists.txt
+++ b/12.16-asConstant1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
@@ -79,7 +79,8 @@ else()
     if(IS_CLANG)
       add_definitions(-Wno-unused-private-field)
       add_definitions(-Wno-unneeded-internal-declaration)
-      
+      add_definitions(-Wno-unused-but-set-variable)
+
     else()
       add_definitions(-fcoroutines) # required for GCC-10    
       
diff --git a/12.16-asConstant1/main.cpp b/12.16-asConstant1/main.cpp
index 04e3d54..e2443f5 100644
--- a/12.16-asConstant1/main.cpp
+++ b/12.16-asConstant1/main.cpp
@@ -15,5 +15,5 @@ int main()
 {
   auto value2 = as_constant(ExpensiveCalculation(2));  // #B compile-time
 
-  ++value2;  // #C Compiles
+  ++value2;                                            // #C Compiles
 }
\ No newline at end of file
diff --git a/12.18-constevalParmCheck0/CMakeLists.txt b/12.18-constevalParmCheck0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/12.18-constevalParmCheck0/CMakeLists.txt
+++ b/12.18-constevalParmCheck0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/12.19-constevalParmCheck1/CMakeLists.txt b/12.19-constevalParmCheck1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/12.19-constevalParmCheck1/CMakeLists.txt
+++ b/12.19-constevalParmCheck1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/12.19-constevalParmCheck1/main.cpp b/12.19-constevalParmCheck1/main.cpp
index f512ddc..68a51fa 100644
--- a/12.19-constevalParmCheck1/main.cpp
+++ b/12.19-constevalParmCheck1/main.cpp
@@ -150,7 +150,7 @@ struct basic_format_string {
   std::string_view str;  // #A Holds the actual format string
 
   template<class T>
-  requires std::is_convertible_v<const T&, std::string_view>
+    requires std::is_convertible_v<const T&, std::string_view>
   consteval basic_format_string(
     const T& s)  // #B A consteval constructor
   : str{s}
diff --git a/12.21-constantEvalutedAndConsteval0/CMakeLists.txt b/12.21-constantEvalutedAndConsteval0/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/12.21-constantEvalutedAndConsteval0/CMakeLists.txt
+++ b/12.21-constantEvalutedAndConsteval0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/12.22-constantEvalutedAndConsteval1/CMakeLists.txt b/12.22-constantEvalutedAndConsteval1/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/12.22-constantEvalutedAndConsteval1/CMakeLists.txt
+++ b/12.22-constantEvalutedAndConsteval1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/12.23-constexprStaticInitFiasco0/CMakeLists.txt b/12.23-constexprStaticInitFiasco0/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/12.23-constexprStaticInitFiasco0/CMakeLists.txt
+++ b/12.23-constexprStaticInitFiasco0/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/12.24-constexprStaticInitFiasco1/CMakeLists.txt b/12.24-constexprStaticInitFiasco1/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/12.24-constexprStaticInitFiasco1/CMakeLists.txt
+++ b/12.24-constexprStaticInitFiasco1/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/12.25-constexprStaticInitFiasco2/CMakeLists.txt b/12.25-constexprStaticInitFiasco2/CMakeLists.txt
index 114d0a0..bdeed93 100644
--- a/12.25-constexprStaticInitFiasco2/CMakeLists.txt
+++ b/12.25-constexprStaticInitFiasco2/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 17)
diff --git a/12.26-constexprStaticInitFiasco3/CMakeLists.txt b/12.26-constexprStaticInitFiasco3/CMakeLists.txt
index ed3d91e..03d498a 100644
--- a/12.26-constexprStaticInitFiasco3/CMakeLists.txt
+++ b/12.26-constexprStaticInitFiasco3/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 set(CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_STANDARD 20)
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 93f781a..a2b239a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,7 +1,7 @@
 # Copyright (c) Andreas Fertig.
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 3.16.2 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.28.2 FATAL_ERROR)
 
 project("Programming with C++20 - Concepts, Coroutines, Ranges, and more" CXX)
 
diff --git a/LICENSE.txt b/LICENSE.txt
index 1792830..cdad4ec 100644
--- a/LICENSE.txt
+++ b/LICENSE.txt
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2021 Andreas Fertig
+Copyright (c) 2024 Andreas Fertig
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/Readme.md b/Readme.md
index a367a36..a3bee8e 100644
--- a/Readme.md
+++ b/Readme.md
@@ -1,4 +1,4 @@
-# Companion Source Code for "Programming with C++20 - Concepts, Coroutines, Ranges, and more" 1. Edition
+# Companion Source Code for "Programming with C++20 - Concepts, Coroutines, Ranges, and more" 2. Edition
 
 [![Build Status](https://github.com/andreasfertig/programming-with-cpp20/workflows/ci/badge.svg)](https://github.com/andreasfertig/programming-with-cpp20/actions/) [![License](https://img.shields.io/badge/license-MIT-blue.svg)](/LICENSE.txt)
 
@@ -6,7 +6,7 @@
 
 ## Code examples
 
-This repository contains runnable source code examples from the 1. edition of [Programming with C++20 - Concepts, Coroutines, Ranges, and more](https://andreasfertig.com/books/programming-with-cpp20/), by [Andreas Fertig](https://andreasfertig.com).
+This repository contains runnable source code examples from the 2. edition of [Programming with C++20 - Concepts, Coroutines, Ranges, and more](https://andreasfertig.com/books/programming-with-cpp20/), by [Andreas Fertig](https://andreasfertig.com).
 
 ### The layout of the examples
 
@@ -14,8 +14,8 @@ The examples are separated into different directories based on how they appear i
 
 ### Running the examples
 
-The examples are contained in a single `.cpp` file that can be easily executed in any IDE. There is also an `CMakeLists.txt` which can generate IDE projects or used to compile the example in a terminal.
-This repo contains a top-level `CMakeLists.txt` which does build all the examples.
+The examples are in a single `.cpp` file that can be easily executed in any IDE. There is also an `CMakeLists.txt` which can generate IDE projects or be used to compile the example in a terminal.
+This repo contains a top-level `CMakeLists.txt`, which does build all the examples.
 
 ### Building the examples
 
@@ -31,9 +31,9 @@ cmake ../
 cmake --build . -j
 ```
 
-After that you find all the executables in `programming-with-cpp20/build/bin`.
+After that, you find all the executables in `programming-with-cpp20/build/bin`.
 
-Some of these examples use the latest C++ standard, so you will need a modern compiler in order to compile them. The latest stable versions of GCC or [Clang](https://releases.llvm.org/) are recommended. The code is not tested, but expected to work, with MSVC as well.
+Some examples use the latest C++ standard, so you will need a modern compiler to compile them. The latest stable versions of GCC or [Clang](https://releases.llvm.org/) are recommended. The code is not tested but is also expected to work with MSVC.
 
 ## License