[Python-checkins] r87675 - python/branches/release31-maint/Lib/collections.py

Mon Jan 3 09:50:48 CET 2011

Author: raymond.hettinger
Date: Mon Jan 3 09:50:48 2011
New Revision: 87675
Log:
Backport r87672 and r87615, improving tests, using super() instead of direct parent references, and using __reduce__ method for pickling.
Modified:
 python/branches/release31-maint/Lib/collections.py
Modified: python/branches/release31-maint/Lib/collections.py
==============================================================================

--- python/branches/release31-maint/Lib/collections.py	(original)
+++ python/branches/release31-maint/Lib/collections.py	Mon Jan 3 09:50:48 2011
@@ -298,16 +298,16 @@
 or multiset. Elements are stored as dictionary keys and their counts
 are stored as dictionary values.
 
- >>> c = Counter('abracadabra') # count elements from a string
+ >>> c = Counter('abcdeabcdabcaba') # count elements from a string
 
 >>> c.most_common(3) # three most common elements
- [('a', 5), ('r', 2), ('b', 2)]
+ [('a', 5), ('b', 4), ('c', 3)]
 >>> sorted(c) # list all unique elements
- ['a', 'b', 'c', 'd', 'r']
+ ['a', 'b', 'c', 'd', 'e']
 >>> ''.join(sorted(c.elements())) # list elements with repetitions
- 'aaaaabbcdrr'
+ 'aaaaabbbbcccdde'
 >>> sum(c.values()) # total of all counts
- 11
+ 15
 
 >>> c['a'] # count of letter 'a'
 5
@@ -315,8 +315,8 @@
 ... c[elem] += 1 # by adding 1 to each element's count
 >>> c['a'] # now there are seven 'a'
 7
- >>> del c['r'] # remove all 'r'
- >>> c['r'] # now there are zero 'r'
+ >>> del c['b'] # remove all 'b'
+ >>> c['b'] # now there are zero 'b'
 0
 
 >>> d = Counter('simsalabim') # make another counter
@@ -355,6 +355,7 @@
 >>> c = Counter(a=4, b=2) # a new counter from keyword args
 
 '''
+ super().__init__()
 self.update(iterable, **kwds)
 
 def __missing__(self, key):
@@ -366,8 +367,8 @@
 '''List the n most common elements and their counts from the most
 common to the least. If n is None, then list all element counts.
 
- >>> Counter('abracadabra').most_common(3)
- [('a', 5), ('r', 2), ('b', 2)]
+ >>> Counter('abcdeabcdabcaba').most_common(3)
+ [('a', 5), ('b', 4), ('c', 3)]
 
 '''
 # Emulate Bag.sortedByCount from Smalltalk
@@ -433,7 +434,7 @@
 for elem, count in iterable.items():
 self[elem] = count + self_get(elem, 0)
 else:
- dict.update(self, iterable) # fast path when counter is empty
+ super().update(iterable) # fast path when counter is empty
 else:
 self_get = self.get
 for elem in iterable:
@@ -445,10 +446,13 @@
 'Like dict.copy() but returns a Counter instance instead of a dict.'
 return Counter(self)
 
+ def __reduce__(self):
+ return self.__class__, (dict(self),)
+
 def __delitem__(self, elem):
 'Like dict.__delitem__() but does not raise KeyError for missing values.'
 if elem in self:
- dict.__delitem__(self, elem)
+ super().__delitem__(elem)
 
 def __repr__(self):
 if not self:
