From 6fd4cfbf274dd43c03bc89efead1890ae1915f42 Mon Sep 17 00:00:00 2001
From: "Vladimir (Alkenso)" <alkensox@gmail.com>
Date: Fri, 16 Aug 2019 09:34:00 +0300
Subject: [PATCH] Update README.md

---
 README.md | 79 +++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 71 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index 0668529..4e2f347 100644
--- a/README.md
+++ b/README.md
@@ -6,15 +6,16 @@ asenum is C++ implementation of very neat enums from Swift language (https://doc
 asenum combines Enum and Variant: it allows to create lighweight wrapper around plain C++ enum and add ability to assign different value types to different cases.
 
 ## Features
-- each enum case can be associated with different type
+- each enum case can be associated with any type
 - values are immutable: totally thread-safe
 - simple interface
 - lightweight, header-only, single file library
 - requires only C++11
+- convenient switch, map, equality, comparison
 
-## Example
+## Simple example
 ```
-// For more examples see tests
+// More examples you can find in tests
 #include <asenum/asenum.h>
 
 #include <string>
@@ -37,9 +38,9 @@ asenum::Case11<ErrorCode, ErrorCode::Timeout, std::chrono::seconds>
 >;
 
 // ===== USAGE =====
-void LogSetting(const AnyError& event)
+void LogError(const AnyError& error)
 {
-    event.doSwitch()
+    error.doSwitch()
     .ifCase<ErrorCode::Unknown>([] (const std::string& value) {
         std::cout << "Unknown error: " << value << "\n";
     })
@@ -57,11 +58,73 @@ void LogSetting(const AnyError& event)
 int main()
 {
     // ===== CREATION =====
-    LogSetting(AnyError::create<ErrorCode::Unknown>("test.api.com"));
-    LogSetting(AnyError::create<ErrorCode::Success>());
-    LogSetting(AnyError::create<ErrorCode::Timeout>(std::chrono::seconds(1)));
+    LogError(AnyError::create<ErrorCode::Unknown>("test.api.com"));
+    LogError(AnyError::create<ErrorCode::Success>());
+    LogError(AnyError::create<ErrorCode::Timeout>(std::chrono::seconds(1)));
     
     return 0;
 }
 ```
 
+## Mapping
+AsEnum supports mapping to any desired type
+*Note: if all cases covered by mapping, it doesn't require 'default' case*
+```
+// ===== Mapping ======
+std::string ErrorToString(const AnyError& error)
+{
+    // All cases covered
+    const auto stringRepresentation = error.doMap<std::string>()
+    .ifCase<ErrorCode::Unknown>([] (const std::string& value) {
+        return value;
+    })
+    .ifCase<ErrorCode::Success>([] {
+        return "Success";
+    })
+    .ifCase<ErrorCode::Timeout>([] (const std::chrono::seconds& value) {
+        return "Timed out after: " + std::to_string(value.count());
+    });
+    
+    return stringRepresentation;
+}
+
+// ===== Partial Mapping ======
+std::string ErrorToString2(const AnyError& error)
+{
+    // All cases covered
+    const auto stringRepresentation = error.doMap<std::string>()
+    .ifCase<ErrorCode::Success>([] {
+        return "Success";
+    })
+    .ifDefault([] {
+        return "Unknown error";
+    });
+    
+    return stringRepresentation;
+}
+```
+
+## Equality and Comparison
+AsEnum provides native way of comparing values
+```
+void Equality(const AnyError& error1, const AnyError& error2)
+{
+    // We can check if error1 == error2
+    // Cases differ => NOT Equal
+    // Cases same AND underlying values same => Equal
+    
+    const bool equal = error1 == error2;
+}
+
+void Comparability(const AnyError& error1, const AnyError& error2)
+{
+    // We can check how error1 relates to error2
+    // Cases of error1 and error2 differ => Compare case ordering
+    // Cases same => Compare underlying values
+    
+    const bool less = error1 < error2;
+    const bool lessEqual = error1 <= error2;
+    const bool greater = error1 > error2;
+    const bool greaterEqual = error1 >= error2;
+}
+```