Sync Word Count with problem specifications

Fixes #200

exercises/practice/word-count/.meta/example.lfe

@@ -3,18 +3,30 @@
 
 (defun count (string)
   (lists:foldl
-    (lambda (k acc)
-      (dict:update_counter k 1 acc))
+    (lambda (word acc)
+      (dict:update_counter word 1 acc))
     (dict:new)
     (tokenize (string:to_lower string))))
 
-(defun alnum? (char) (orelse (=< #\a char #\z) (=< #\0 char #\9)))
+(defun unquote
+  (((cons #\' remaining))
+    (case (lists:last remaining)
+      (#\' (lists:sublist remaining 1 (- (length remaining) 1)))
+      (_ (cons #\' remaining))))
+  ((word) word))
 
-(defun sep? (char) (not (alnum? char)))
+(defun tokenize-loop
+  ; End of sentence with no more words
+  (('() '() acc) acc)
+  ; End of sentence with one more word
+  (('() word-acc acc) (cons (unquote (lists:reverse word-acc)) acc))
+  ; Lower case character, number or apostrophe
+  (((cons char remaining) word-acc acc)
+    (when (or (and (>= char #\a) (=< char #\z)) (and (>= char #\0) (=< char #\9)) (== char #\')))
+    (tokenize-loop remaining (cons char word-acc) acc))
+  ; Boundary or junk with no word in word accumulator (skip it)
+  (((cons _ remaining) '() acc) (tokenize-loop remaining '() acc))
+  ; Boundary or junk with something in word accumulator (add the word to the accumulator)
+  (((cons _ remaining) word-acc acc) (tokenize-loop remaining '() (cons (unquote (lists:reverse word-acc)) acc))))
 
-(defun tokenize
-  ([()] ())
-  ([string]
-   (case (lists:splitwith #'alnum?/1 (lists:dropwhile #'sep?/1 string))
-     (`#([] ,rest)    (tokenize rest))
-     (`#(,word ,rest) (cons word (tokenize rest))))))
+(defun tokenize (text) (tokenize-loop text '() '()))

exercises/practice/word-count/src/word-count.app.src

@@ -1,6 +1,7 @@
 %% -*- erlang -*-
 {application, 'word-count',
- [{description, ""},
+ [{description, "Given a phrase, count the occurrences of each word in that phrase."
+},
   {vsn, "0.0.1"},
   {modules,
    ['word-count']},

exercises/practice/word-count/src/word-count.lfe

@@ -0,0 +1,4 @@
+(defmodule word-count
+  (export (count 1)))
+
+; Please implement the `count` function

exercises/practice/word-count/test/word-count-tests.lfe

@@ -27,9 +27,23 @@
       #("red"  1)
       #("blue" 1))))
 
+(deftest handles-cramped-lists
+  (assert-count
+    "one,two,three"
+    '(#("one" 1)
+      #("two" 1)
+      #("three" 1))))
+
+(deftest handles-expanded-lists
+  (assert-count
+    "one,\ntwo,\nthree"
+    '(#("one" 1)
+      #("two" 1)
+      #("three" 1))))
+
 (deftest ignore-punctuation
   (assert-count
-    "car : carpet as java : javascript!!&@$%^&"
+    "car: carpet as java: javascript!!&@$%^&"
     '(#("car"        1)
       #("carpet"     1)
       #("as"         1)
@@ -45,8 +59,71 @@
 
 (deftest normalize-case
   (assert-count
-    "go Go GO"
-    '(#("go"  3))))
+    "go Go GO Stop stop"
+    '(#("go" 3)
+      #("stop" 2))))
+
+(deftest with-apostrophes
+  (assert-count
+    "First: don't laugh. Then: don't cry."
+    '(#("first" 1)
+      #("don't" 2)
+      #("laugh" 1)
+      #("then" 1)
+      #("cry" 1))))
+
+(deftest with-apostrophes-multiple-letters
+  (assert-count
+    "First don't laugh. then: don't cry. You're getting it."
+    '(#("first" 1)
+      #("don't" 2)
+      #("laugh" 1)
+      #("then" 1)
+      #("cry" 1)
+      #("you're" 1)
+      #("getting" 1)
+      #("it" 1))))
+
+(deftest with-quotations
+  (assert-count
+    "Joe can't tell between 'large' and large."
+    '(#("joe" 1)
+      #("can't" 1)
+      #("tell" 1)
+      #("between" 1)
+      #("large" 2)
+      #("and" 1))))
+
+(deftest substrings-from-the-beginning
+  (assert-count
+    "Joe can't tell between app, apple and a."
+    '(#("joe" 1)
+      #("can't" 1)
+      #("tell" 1)
+      #("between" 1)
+      #("app" 1)
+      #("apple" 1)
+      #("and" 1)
+      #("a" 1))))
+
+(deftest multiple-spaces-not-detected-as-a-word
+  (assert-count
+    " multiple   whitespaces"
+    '(#("multiple" 1)
+      #("whitespaces" 1))))
+
+(deftest alternating-word-separators-not-detected-as-a-word
+  (assert-count
+    ",\n,one,\n ,two \n 'three'"
+    '(#("one" 1)
+      #("two" 1)
+      #("three" 1))))
+
+(deftest quotation-for-word-with-apostrophe
+  (assert-count
+    "can, can't, 'can't'"
+    '(#("can" 1)
+      #("can't" 2))))
 
 (deftest prefix-punctuation
   (assert-count