cpython-lru_cache-weakref: Lib/Queue.py annotate

annotate Lib/Queue.py @ 34161:ca2ca1aeb080 2.4

Check in missing png version of pyfav.gif.

author	Johannes Gijsbers <jlg@dds.nl>
date	Mon, 13 Dec 2004 13:11:42 +0000
parents	d42efc2b45e9
children	f731859e9b3b bed3f52f0dc6

rev	line source
11691 e34991022571 Mass patch by Ka-Ping Yee: Guido van Rossum <guido@python.org> parents: 11267 diff changeset	1 """A multi-producer, multi-consumer queue."""
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	2
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	3 from time import time as _time
31436 63fa60f2d61c * Move collections.deque() in from the sandbox Raymond Hettinger <python@rcn.com> parents: 29711 diff changeset	4 from collections import deque
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	5
29711 58132c813d7b Add __all__ . Brett Cannon <bcannon@gmail.com> parents: 26892 diff changeset	6 __all__ = ['Empty', 'Full', 'Queue']
58132c813d7b Add __all__ . Brett Cannon <bcannon@gmail.com> parents: 26892 diff changeset	7
15902 eef321b6e41c Variant of Skip's patch 103246 (Remove unneeded string exception compat from Queue). Tim Peters <tim.peters@gmail.com> parents: 13050 diff changeset	8 class Empty(Exception):
eef321b6e41c Variant of Skip's patch 103246 (Remove unneeded string exception compat from Queue). Tim Peters <tim.peters@gmail.com> parents: 13050 diff changeset	9 "Exception raised by Queue.get(block=0)/get_nowait()."
eef321b6e41c Variant of Skip's patch 103246 (Remove unneeded string exception compat from Queue). Tim Peters <tim.peters@gmail.com> parents: 13050 diff changeset	10 pass
eef321b6e41c Variant of Skip's patch 103246 (Remove unneeded string exception compat from Queue). Tim Peters <tim.peters@gmail.com> parents: 13050 diff changeset	11
eef321b6e41c Variant of Skip's patch 103246 (Remove unneeded string exception compat from Queue). Tim Peters <tim.peters@gmail.com> parents: 13050 diff changeset	12 class Full(Exception):
eef321b6e41c Variant of Skip's patch 103246 (Remove unneeded string exception compat from Queue). Tim Peters <tim.peters@gmail.com> parents: 13050 diff changeset	13 "Exception raised by Queue.put(block=0)/put_nowait()."
eef321b6e41c Variant of Skip's patch 103246 (Remove unneeded string exception compat from Queue). Tim Peters <tim.peters@gmail.com> parents: 13050 diff changeset	14 pass
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	15
f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	16 class Queue:
11267 2b26e48a85a6 Make the maxsize constructor argument default to 0 (an unlimited queue size). Guido van Rossum <guido@python.org> parents: 10120 diff changeset	17 def __init__(self, maxsize=0):
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	18 """Initialize a queue object with a given maximum size.
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	19
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	20 If maxsize is <= 0, the queue size is infinite.
fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	21 """
26892 95510f0a0624 Use the dummy_thread module in Queue.py and tempfile.py. Guido van Rossum <guido@python.org> parents: 25796 diff changeset	22 try:
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	23 import threading
26892 95510f0a0624 Use the dummy_thread module in Queue.py and tempfile.py. Guido van Rossum <guido@python.org> parents: 25796 diff changeset	24 except ImportError:
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	25 import dummy_threading as threading
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	26 self._init(maxsize)
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	27 # mutex must be held whenever the queue is mutating. All methods
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	28 # that acquire mutex must release it before returning. mutex
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	29 # is shared between the two conditions, so acquiring and
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	30 # releasing the conditions also acquires and releases mutex.
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	31 self.mutex = threading.Lock()
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	32 # Notify not_empty whenever an item is added to the queue; a
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	33 # thread waiting to get is notified then.
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	34 self.not_empty = threading.Condition(self.mutex)
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	35 # Notify not_full whenever an item is removed from the queue;
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	36 # a thread waiting to put is notified then.
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	37 self.not_full = threading.Condition(self.mutex)
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	38
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	39 def qsize(self):
10120 5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	40 """Return the approximate size of the queue (not reliable!)."""
8197 3a55b4c5e3c7 Replace all calls to acquire_lock() and release_lock() with acquire() Guido van Rossum <guido@python.org> parents: 7926 diff changeset	41 self.mutex.acquire()
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	42 n = self._qsize()
8197 3a55b4c5e3c7 Replace all calls to acquire_lock() and release_lock() with acquire() Guido van Rossum <guido@python.org> parents: 7926 diff changeset	43 self.mutex.release()
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	44 return n
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	45
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	46 def empty(self):
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	47 """Return True if the queue is empty, False otherwise (not reliable!)."""
8197 3a55b4c5e3c7 Replace all calls to acquire_lock() and release_lock() with acquire() Guido van Rossum <guido@python.org> parents: 7926 diff changeset	48 self.mutex.acquire()
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	49 n = self._empty()
8197 3a55b4c5e3c7 Replace all calls to acquire_lock() and release_lock() with acquire() Guido van Rossum <guido@python.org> parents: 7926 diff changeset	50 self.mutex.release()
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	51 return n
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	52
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	53 def full(self):
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	54 """Return True if the queue is full, False otherwise (not reliable!)."""
8197 3a55b4c5e3c7 Replace all calls to acquire_lock() and release_lock() with acquire() Guido van Rossum <guido@python.org> parents: 7926 diff changeset	55 self.mutex.acquire()
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	56 n = self._full()
8197 3a55b4c5e3c7 Replace all calls to acquire_lock() and release_lock() with acquire() Guido van Rossum <guido@python.org> parents: 7926 diff changeset	57 self.mutex.release()
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	58 return n
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	59
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	60 def put(self, item, block=True, timeout=None):
7926 e29d435ab142 Clarify that put blocks when the queue is full. Add some blank Guido van Rossum <guido@python.org> parents: 7755 diff changeset	61 """Put an item into the queue.
e29d435ab142 Clarify that put blocks when the queue is full. Add some blank Guido van Rossum <guido@python.org> parents: 7755 diff changeset	62
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	63 If optional args 'block' is true and 'timeout' is None (the default),
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	64 block if necessary until a free slot is available. If 'timeout' is
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	65 a positive number, it blocks at most 'timeout' seconds and raises
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	66 the Full exception if no free slot was available within that time.
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	67 Otherwise ('block' is false), put an item on the queue if a free slot
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	68 is immediately available, else raise the Full exception ('timeout'
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	69 is ignored in that case).
10120 5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	70 """
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	71 self.not_full.acquire()
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	72 try:
32625 d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	73 if not block:
d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	74 if self._full():
d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	75 raise Full
d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	76 elif timeout is None:
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	77 while self._full():
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	78 self.not_full.wait()
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	79 else:
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	80 if timeout < 0:
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	81 raise ValueError("'timeout' must be a positive number")
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	82 endtime = _time() + timeout
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	83 while self._full():
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	84 remaining = endtime - _time()
32625 d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	85 if remaining <= 0.0:
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	86 raise Full
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	87 self.not_full.wait(remaining)
23160 c548e726b3bc Fix bug 544473 - "Queue module can deadlock". Mark Hammond <mhammond@skippinet.com.au> parents: 16657 diff changeset	88 self._put(item)
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	89 self.not_empty.notify()
23160 c548e726b3bc Fix bug 544473 - "Queue module can deadlock". Mark Hammond <mhammond@skippinet.com.au> parents: 16657 diff changeset	90 finally:
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	91 self.not_full.release()
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	92
10120 5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	93 def put_nowait(self, item):
5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	94 """Put an item into the queue without blocking.
5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	95
5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	96 Only enqueue the item if a free slot is immediately available.
5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	97 Otherwise raise the Full exception.
5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	98 """
32625 d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	99 return self.put(item, False)
7926 e29d435ab142 Clarify that put blocks when the queue is full. Add some blank Guido van Rossum <guido@python.org> parents: 7755 diff changeset	100
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	101 def get(self, block=True, timeout=None):
10120 5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	102 """Remove and return an item from the queue.
5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	103
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	104 If optional args 'block' is true and 'timeout' is None (the default),
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	105 block if necessary until an item is available. If 'timeout' is
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	106 a positive number, it blocks at most 'timeout' seconds and raises
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	107 the Empty exception if no item was available within that time.
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	108 Otherwise ('block' is false), return an item if one is immediately
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	109 available, else raise the Empty exception ('timeout' is ignored
3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	110 in that case).
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	111 """
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	112 self.not_empty.acquire()
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	113 try:
32625 d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	114 if not block:
d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	115 if self._empty():
d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	116 raise Empty
d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	117 elif timeout is None:
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	118 while self._empty():
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	119 self.not_empty.wait()
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	120 else:
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	121 if timeout < 0:
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	122 raise ValueError("'timeout' must be a positive number")
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	123 endtime = _time() + timeout
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	124 while self._empty():
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	125 remaining = endtime - _time()
32625 d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	126 if remaining <= 0.0:
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	127 raise Empty
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	128 self.not_empty.wait(remaining)
23160 c548e726b3bc Fix bug 544473 - "Queue module can deadlock". Mark Hammond <mhammond@skippinet.com.au> parents: 16657 diff changeset	129 item = self._get()
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	130 self.not_full.notify()
73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	131 return item
23160 c548e726b3bc Fix bug 544473 - "Queue module can deadlock". Mark Hammond <mhammond@skippinet.com.au> parents: 16657 diff changeset	132 finally:
32624 73016bd01a71 Bug #788520: Queue class has logic error when non-blocking Tim Peters <tim.peters@gmail.com> parents: 31436 diff changeset	133 self.not_empty.release()
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	134
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	135 def get_nowait(self):
10120 5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	136 """Remove and return an item from the queue without blocking.
7926 e29d435ab142 Clarify that put blocks when the queue is full. Add some blank Guido van Rossum <guido@python.org> parents: 7755 diff changeset	137
25796 3eafbde56b21 Patch #572628: Optional timeouts for put and get. Martin v. Löwis <martin@v.loewis.de> parents: 24058 diff changeset	138 Only get an item if one is immediately available. Otherwise
10120 5b15642e7bdf Tim Peters: Guido van Rossum <guido@python.org> parents: 8197 diff changeset	139 raise the Empty exception.
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	140 """
32625 d42efc2b45e9 Simplified the new get/get_nowait/put/put_nowait implementations a bit. Tim Peters <tim.peters@gmail.com> parents: 32624 diff changeset	141 return self.get(False)
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	142
4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	143 # Override these methods to implement other queue organizations
4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	144 # (e.g. stack or priority queue).
4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	145 # These will only be called with appropriate locks held
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	146
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	147 # Initialize the queue representation
4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	148 def _init(self, maxsize):
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	149 self.maxsize = maxsize
31436 63fa60f2d61c * Move collections.deque() in from the sandbox Raymond Hettinger <python@rcn.com> parents: 29711 diff changeset	150 self.queue = deque()
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	151
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	152 def _qsize(self):
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	153 return len(self.queue)
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	154
13050 a195962e389c typos fixed by Rob Hooft Jeremy Hylton <jeremy@alum.mit.edu> parents: 11691 diff changeset	155 # Check whether the queue is empty
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	156 def _empty(self):
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	157 return not self.queue
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	158
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	159 # Check whether the queue is full
4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	160 def _full(self):
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	161 return self.maxsize > 0 and len(self.queue) == self.maxsize
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	162
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	163 # Put a new item in the queue
4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	164 def _put(self, item):
7755 fb4b4d069cc7 Mass check-in after untabifying all files that need it. Guido van Rossum <guido@python.org> parents: 6612 diff changeset	165 self.queue.append(item)
995 f025eef93130 New module implementing a multi-everything queue. Guido van Rossum <guido@python.org> parents: diff changeset	166
6612 4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	167 # Get an item from the queue
4b2d8dc92db4 (Queue.Empty): When class based exceptions are in force, derive this Barry Warsaw <barry@python.org> parents: 1463 diff changeset	168 def _get(self):
31436 63fa60f2d61c * Move collections.deque() in from the sandbox Raymond Hettinger <python@rcn.com> parents: 29711 diff changeset	169 return self.queue.popleft()

Mercurial > cpython-lru_cache-weakref

annotate Lib/Queue.py @ 34161:ca2ca1aeb080 2.4