Eliminate the use of global variables; makes the example cleaner.

07-infinite-mirror/tf-07.py

@@ -7,7 +7,7 @@ RECURSION_LIMIT = 9500
 # this doesn't just rule recursion: it rules the depth of the call stack
 sys.setrecursionlimit(RECURSION_LIMIT+10)
 
-def count(word_list, word_freqs):
+def count(word_list, stopwords, wordfreqs):
     # What to do with an empty list
     if word_list == []:
         return
@@ -16,33 +16,33 @@ def count(word_list, word_freqs):
         word = word_list[0]
         if word not in stopwords:
             if word in word_freqs:
-                word_freqs[word] += 1
+                wordfreqs[word] += 1
             else:
-                word_freqs[word] = 1
+                wordfreqs[word] = 1
     # The inductive case, what to do with a list of words
     else:
         # Process the head word
-        count([word_list[0]], word_freqs)
+        count([word_list[0]], stopwords, wordfreqs)
         # Process the tail 
-        count(word_list[1:], word_freqs)
+        count(word_list[1:], stopwords, wordfreqs)
 
-def wf_print(word_freq):
-    if word_freq == []:
+def wf_print(wordfreq):
+    if wordfreq == []:
         return
-    if len(word_freq) == 1:
-        (w, c) = word_freq[0]
+    if len(wordfreq) == 1:
+        (w, c) = wordfreq[0]
         print w, '-', c
     else:
-        wf_print([word_freq[0]])
-        wf_print(word_freq[1:])
+        wf_print([wordfreq[0]])
+        wf_print(wordfreq[1:])
 
-stopwords = set(open('../stop_words.txt').read().split(','))
+stop_words = set(open('../stop_words.txt').read().split(','))
 words = re.findall('[a-z]{2,}', open(sys.argv[1]).read().lower())
 word_freqs = {}
 # Theoretically, we would just call count(words, word_freqs)
 # Try doing that and see what happens.
 for i in range(0, len(words), RECURSION_LIMIT):
-    count(words[i:i+RECURSION_LIMIT], word_freqs)
+    count(words[i:i+RECURSION_LIMIT], stop_words, word_freqs)
 
 wf_print(sorted(word_freqs.iteritems(), key=operator.itemgetter(1), reverse=True)[:25])