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* Move collections.deque() in from the sandbox
* Add unittests, newsitem, and whatsnew * Apply to Queue.py mutex.py threading.py pydoc.py and shlex.py * Docs are forthcoming
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Lines changed: 982 additions & 56 deletions

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‎Doc/lib/libbisect.tex‎

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@@ -80,22 +80,5 @@ \subsection{Examples}
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'C'
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>>> map(grade, [33, 99, 77, 44, 12, 88])
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['E', 'A', 'B', 'D', 'F', 'A']
83-
\end{verbatim}
84-
85-
The bisect module can be used with the Queue module to implement a priority
86-
queue (example courtesy of Fredrik Lundh): \index{Priority Queue}
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\begin{verbatim}
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import Queue, bisect
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class PriorityQueue(Queue.Queue):
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def _put(self, item):
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bisect.insort(self.queue, item)
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# usage
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queue = PriorityQueue(0)
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queue.put((2, "second"))
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queue.put((1, "first"))
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queue.put((3, "third"))
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priority, value = queue.get()
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\end{verbatim}

‎Doc/lib/libqueue.tex‎

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@@ -12,10 +12,6 @@ \section{\module{Queue} ---
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semantics. It depends on the availability of thread support in
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Python.
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\begin{seealso}
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\seemodule{bisect}{PriorityQueue example using the Queue class}
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\end{seealso}
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The \module{Queue} module defines the following class and exception:
2016

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‎Doc/whatsnew/whatsnew24.tex‎

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@@ -322,6 +322,31 @@ \section{New, Improved, and Deprecated Modules}
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\item Korean: cp949, euc-kr, johab, iso-2022-kr
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\end{itemize}
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\item There is a new \module{collections} module which currently offers
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just one new datatype, \class{deque}, which offers high-performance,
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thread-safe, memory friendly appends and pops on either side of the
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deque resulting in efficient stacks and queues:
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\begin{verbatim}
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>>> from collections import deque
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>>> d = deque('ghi') # make a new deque with three items
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>>> d.append('j') # add a new entry to the right side
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>>> d.appendleft('f') # add a new entry to the left side
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>>> d # show the representation of the deque
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deque(['f', 'g', 'h', 'i', 'j'])
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>>> d.pop() # return and remove the rightmost item
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'j'
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>>> d.popleft() # return and remove the leftmost item
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'f'
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>>> list(d) # list the contents of the deque
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['g', 'h', 'i']
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>>> 'h' in d # search the deque
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True
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\end{verbatim}
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Several modules now take advantage of \class{collections.deque()} for
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improved performance: \module{Queue}, \module{mutex}, \module{shlex}
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\module{threading}, and \module{pydoc}.
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\item The \module{heapq} module has been converted to C. The resulting
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ten-fold improvement in speed makes the module suitable for handling

‎Lib/Queue.py‎

Lines changed: 3 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
11
"""A multi-producer, multi-consumer queue."""
22

33
from time import time as _time, sleep as _sleep
4+
from collections import deque
45

56
__all__ = ['Empty', 'Full', 'Queue']
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@@ -184,7 +185,7 @@ def get_nowait(self):
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# Initialize the queue representation
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def _init(self, maxsize):
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self.maxsize = maxsize
187-
self.queue = []
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self.queue = deque()
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189190
def _qsize(self):
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return len(self.queue)
@@ -203,4 +204,4 @@ def _put(self, item):
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# Get an item from the queue
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def _get(self):
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return self.queue.pop(0)
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return self.queue.popleft()

‎Lib/mutex.py‎

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Original file line numberDiff line numberDiff line change
@@ -12,11 +12,13 @@
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for lock, where a function is called once the lock is aquired.
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"""
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from collections import deque
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class mutex:
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def __init__(self):
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"""Create a new mutex -- initially unlocked."""
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self.locked = 0
19-
self.queue = []
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self.queue = deque()
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2123
def test(self):
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"""Test the locked bit of the mutex."""
@@ -44,7 +46,7 @@ def unlock(self):
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"""Unlock a mutex. If the queue is not empty, call the next
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function with its argument."""
4648
if self.queue:
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function, argument = self.queue.pop(0)
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function, argument = self.queue.popleft()
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function(argument)
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else:
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self.locked = 0

‎Lib/pydoc.py‎

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@@ -55,6 +55,7 @@ class or function within a module or module in a package. If the
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import sys, imp, os, re, types, inspect, __builtin__
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from repr import Repr
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from string import expandtabs, find, join, lower, split, strip, rfind, rstrip
58+
from collections import deque
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5960
# --------------------------------------------------------- common routines
6061

@@ -685,7 +686,7 @@ def maybe(self):
685686
hr = HorizontalRule()
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687688
# List the mro, if non-trivial.
688-
mro = list(inspect.getmro(object))
689+
mro = deque(inspect.getmro(object))
689690
if len(mro) > 2:
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hr.maybe()
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push('<dl><dt>Method resolution order:</dt>\n')
@@ -763,7 +764,7 @@ def spilldata(msg, attrs, predicate):
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764765
while attrs:
765766
if mro:
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thisclass = mro.pop(0)
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thisclass = mro.popleft()
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else:
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thisclass = attrs[0][2]
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attrs, inherited = _split_list(attrs, lambda t: t[2] is thisclass)
@@ -1083,7 +1084,7 @@ def makename(c, m=object.__module__):
10831084
push = contents.append
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10851086
# List the mro, if non-trivial.
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mro = list(inspect.getmro(object))
1087+
mro = deque(inspect.getmro(object))
10871088
if len(mro) > 2:
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push("Method resolution order:")
10891090
for base in mro:
@@ -1152,7 +1153,7 @@ def spilldata(msg, attrs, predicate):
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inspect.classify_class_attrs(object))
11531154
while attrs:
11541155
if mro:
1155-
thisclass = mro.pop(0)
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thisclass = mro.popleft()
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else:
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thisclass = attrs[0][2]
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attrs, inherited = _split_list(attrs, lambda t: t[2] is thisclass)

‎Lib/shlex.py‎

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@@ -9,6 +9,7 @@
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import os.path
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import sys
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from collections import deque
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1314
try:
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from cStringIO import StringIO
@@ -45,11 +46,11 @@ def __init__(self, instream=None, infile=None, posix=False):
4546
self.escape = '\\'
4647
self.escapedquotes = '"'
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self.state = ' '
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self.pushback = []
49+
self.pushback = deque()
4950
self.lineno = 1
5051
self.debug = 0
5152
self.token = ''
52-
self.filestack = []
53+
self.filestack = deque()
5354
self.source = None
5455
if self.debug:
5556
print 'shlex: reading from %s, line %d' \
@@ -59,13 +60,13 @@ def push_token(self, tok):
5960
"Push a token onto the stack popped by the get_token method"
6061
if self.debug >= 1:
6162
print "shlex: pushing token " + `tok`
62-
self.pushback.insert(0, tok)
63+
self.pushback.appendleft(tok)
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6465
def push_source(self, newstream, newfile=None):
6566
"Push an input source onto the lexer's input source stack."
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if isinstance(newstream, basestring):
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newstream = StringIO(newstream)
68-
self.filestack.insert(0, (self.infile, self.instream, self.lineno))
69+
self.filestack.appendleft((self.infile, self.instream, self.lineno))
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self.infile = newfile
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self.instream = newstream
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self.lineno = 1
@@ -78,8 +79,7 @@ def push_source(self, newstream, newfile=None):
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def pop_source(self):
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"Pop the input source stack."
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self.instream.close()
81-
(self.infile, self.instream, self.lineno) = self.filestack[0]
82-
self.filestack = self.filestack[1:]
82+
(self.infile, self.instream, self.lineno) = self.filestack.popleft()
8383
if self.debug:
8484
print 'shlex: popping to %s, line %d' \
8585
% (self.instream, self.lineno)
@@ -88,7 +88,7 @@ def pop_source(self):
8888
def get_token(self):
8989
"Get a token from the input stream (or from stack if it's nonempty)"
9090
if self.pushback:
91-
tok = self.pushback.pop(0)
91+
tok = self.pushback.popleft()
9292
if self.debug >= 1:
9393
print "shlex: popping token " + `tok`
9494
return tok
@@ -226,7 +226,7 @@ def read_token(self):
226226
or self.whitespace_split:
227227
self.token = self.token + nextchar
228228
else:
229-
self.pushback.insert(0, nextchar)
229+
self.pushback.appendleft(nextchar)
230230
if self.debug >= 2:
231231
print "shlex: I see punctuation in word state"
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self.state = ' '

‎Lib/test/test_bisect.py‎

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Original file line numberDiff line numberDiff line change
@@ -170,23 +170,6 @@ def test_backcompatibility(self):
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>>> map(grade, [33, 99, 77, 44, 12, 88])
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['E', 'A', 'B', 'D', 'F', 'A']
172172
173-
The bisect module can be used with the Queue module to implement
174-
a priority queue (example courtesy of Fredrik Lundh):
175-
176-
>>> import Queue, bisect
177-
>>> class PriorityQueue(Queue.Queue):
178-
... def _put(self, item):
179-
... bisect.insort(self.queue, item)
180-
...
181-
>>> queue = PriorityQueue(0)
182-
>>> queue.put((2, "second"))
183-
>>> queue.put((1, "first"))
184-
>>> queue.put((3, "third"))
185-
>>> queue.get()
186-
(1, 'first')
187-
>>> queue.get()
188-
(2, 'second')
189-
190173
"""
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#------------------------------------------------------------------------------

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