Add new Chapter 4

src/Levels.purs

@@ -13,11 +13,12 @@ import Levels.Chapter0 (chapter0)
 import Levels.Chapter1 (chapter1)
 import Levels.Chapter2 (chapter2)
 import Levels.Chapter3 (chapter3)
+import Levels.Chapter4 (chapter4)
 import Levels.Chapter5 (chapter5)
 
 -- | A simple list of all available chapters
 allChapters :: List Chapter
-allChapters = chapter0 : chapter1 : chapter2 : chapter3 : chapter5 : Nil
+allChapters = chapter0 : chapter1 : chapter2 : chapter3 : chapter4: chapter5 : Nil
 
 -- | A dictionary of all available levels across the chapters
 allLevels :: SM.StrMap Level

src/Levels/Chapter4.purs

@@ -0,0 +1,83 @@
+module Levels.Chapter4 where
+
+import Data.List (List(..), (:), partition, concat)
+import Data.Maybe (Maybe(..))
+
+import Helper (fromArray, (:->), (:>))
+import ListHelper (contains)
+import Transformer (replaceSingle)
+import Types (Chapter, Transformer, Cube(..), Difficulty(..))
+
+partitionContains :: Cube -> Transformer
+partitionContains cube wall =
+    let parts = partition (contains cube) wall
+    in concat (parts.no : parts.yes : Nil)
+
+chapter4 :: Chapter
+chapter4 = {
+    name: "Chapter 4",
+
+    transformers: fromArray [
+        "replaceYbyR" :> {
+            name: "map {Yellow}↦{Red}",
+            function: replaceSingle Yellow Red
+        },
+        "replaceRbyC" :> {
+            name: "map {Red}↦{Cyan}",
+            function: replaceSingle Red Cyan
+        },
+        "replaceCbyY" :> {
+            name: "map {Cyan}↦{Yellow}",
+            function: replaceSingle Cyan Yellow
+        },
+        "partitionContainsC" :> {
+            name: "partition (contains {Cyan})",
+            function: partitionContains Cyan
+        },
+        "partitionContainsR" :> {
+            name: "partition (contains {Red})",
+            function: partitionContains Red
+        }
+    ],
+
+    levels: fromArray [
+        "4.1" :-> {
+            name: "Take sides!",
+            help: Just """This chapter introduces partitioning. The function `partitionContainsR` reorders the columns
+                          so that the columns which do not contain a red cube are grouped on the left, and the columns
+                          which do are gouped on the right.""",
+            difficulty: Easy,
+            initial: [[Cyan, Red], [Cyan, Cyan], [Red, Red], [Cyan, Cyan], [Cyan, Red]],
+            target: [[Cyan, Cyan], [Cyan, Cyan], [Cyan, Red], [Red, Red], [Cyan, Red]]
+        },
+        "4.2" :-> {
+            name: "Take sides – again!",
+            help: Just """Note that within each partition – the columns which don't satisfy the condition and the
+                          columns which do – the order remains the same as it was prior to partitioning.""",
+            difficulty: Medium,
+            initial: [[Cyan, Red], [Cyan, Cyan], [Red, Red], [Cyan, Cyan], [Cyan, Red]],
+            target: [[Cyan, Cyan], [Cyan, Cyan], [Red, Red], [Cyan, Red], [Cyan, Red]]
+        },
+        "4.3" :-> {
+            name: "Shift",
+            help: Just "Can you partition this?",
+            difficulty: Medium,
+            initial: [[Cyan, Red], [Red, Cyan], [Cyan, Red], [Red, Cyan], [Cyan, Red]],
+            target: [[Red, Cyan], [Cyan, Red], [Red, Cyan], [Cyan, Red], [Red, Cyan]]
+        },
+        "4.4" :-> {
+            name: "Robot eyes",
+            help: Nothing,
+            difficulty: Medium,
+            initial: [[Brown, Brown, Brown], [Brown, Yellow, Brown], [Brown, Brown, Brown], [Brown, Yellow, Brown], [Brown, Brown, Brown]],
+            target: [[Brown, Brown, Brown], [Brown, Brown, Brown], [Brown, Brown, Brown], [Brown, Yellow, Brown], [Brown, Yellow, Brown]]
+        },
+        "4.5" :-> {
+            name: "Mountains",
+            help: Nothing,
+            difficulty: Hard,
+            initial: [[Brown, Brown, Red, Red], [Brown, Brown, Brown, Cyan], [Brown, Yellow, Yellow, Yellow], [Brown, Brown, Brown, Red], [Brown, Brown, Cyan, Cyan], [Brown, Brown, Yellow, Yellow]],
+            target: [[Brown, Cyan, Cyan, Cyan], [Brown, Brown, Cyan, Cyan], [Brown, Brown, Cyan, Cyan], [Brown, Brown, Brown, Cyan], [Brown, Brown, Brown, Cyan], [Brown, Brown, Cyan, Cyan]]
+        }
+    ]
+}