June 2018 Update

Task/Odd-word-problem/Ceylon/odd-word-problem.ceylon

@@ -0,0 +1,33 @@
+String[] meaning = ["what,", "is,", "the;", "meaning,", "of:", "life."];
+String[] kansas = ["we,", "are,", "not,", "in,", "kansas;", "any,", "more."];
+
+shared void run() {
+    print("".join(reverseWords(meaning)));
+    print("".join(reverseWords(kansas)));
+}
+
+String[] reverseWords(String[] words)
+    => recursiveReverseWords(words, []);
+
+String[] recursiveReverseWords(String[] remOrig, String[] revWords)
+    => if (nonempty remOrig)
+        then recursiveReverseWords(remOrig.rest,
+                                   revWords.withTrailing(reverseWordRecursive(remOrig.first.sequence(),
+                                                                              [],
+                                                                              revWords.size.even)))
+        else revWords;
+
+String reverseWordRecursive(Character[] remOldChars, Character[] revChars, Boolean isEven)
+    => if (nonempty remOldChars)
+        then let (char = remOldChars.first) reverseWordRecursive(remOldChars.rest,
+                                                                 conditionalAddChar(char, revChars, isEven),
+                                                                 isEven)
+        else String(revChars);
+
+Character[] conditionalAddChar(Character char, Character[] chars, Boolean isEven)
+    => if (isEven || isPunctuation(char))
+        then chars.withTrailing(char)
+        else chars.withLeading(char);
+
+Boolean isPunctuation(Character char)
+    => ",.:;".contains(char);