iterators and generators chapter

--HG-- rename : humansize.py => examples/humansize.py rename : roman1.py => examples/roman1.py rename : roman2.py => examples/roman2.py rename : roman3.py => examples/roman3.py rename : roman4.py => examples/roman4.py rename : roman5.py => examples/roman5.py rename : roman6.py => examples/roman6.py rename : roman7.py => examples/roman7.py rename : roman8.py => examples/roman8.py rename : romantest1.py => examples/romantest1.py rename : romantest2.py => examples/romantest2.py rename : romantest3.py => examples/romantest3.py rename : romantest4.py => examples/romantest4.py rename : romantest5.py => examples/romantest5.py rename : romantest6.py => examples/romantest6.py rename : romantest7.py => examples/romantest7.py rename : romantest8.py => examples/romantest8.py
2026-06-05 23:10:17 +00:00 · 2009-03-27 01:43:33 -05:00
parent 18b0144075
commit 933dc9459a
52 changed files with 2247 additions and 695 deletions
@@ -0,0 +1,60 @@
+"""Pluralize English nouns (stage 3)
+
+Command line usage:
+$ python plural3.py noun
+nouns
+"""
+
+import re
+
+def build_match_and_apply_functions(pattern, search, replace):
+    def matches_rule(word):
+        return re.search(pattern, word)
+    def apply_rule(word):
+        return re.sub(search, replace, word)
+    return (matches_rule, apply_rule)
+
+patterns = \
+  [
+    ['[sxz]$',           '$',  'es'],
+    ['[^aeioudgkprt]h$', '$',  'es'],
+    ['(qu|[^aeiou])y$',  'y$', 'ies'],
+    ['$',                '$',  's']
+  ]
+rules = [build_match_and_apply_functions(pattern, search, replace)
+         for (pattern, search, replace) in patterns]
+
+def plural(noun):
+    for matches_rule, apply_rule in rules:
+        if matches_rule(noun):
+            return apply_rule(noun)
+
+if __name__ == '__main__':
+    import sys
+    if sys.argv[1:]:
+        print(plural(sys.argv[1]))
+    else:
+        print(__doc__)
+
+# Copyright (c) 2009, Mark Pilgrim, All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without modification,
+# are permitted provided that the following conditions are met:
+# 
+# * Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+# * Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 'AS IS'
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.