Refactor if/elif chain for clarity and speed. Remove dependency on subclasses having to implement _empty and _full.
diff --git a/Lib/Queue.py b/Lib/Queue.py
index 79b0abf..ce34024 100644
--- a/Lib/Queue.py
+++ b/Lib/Queue.py
@@ -23,6 +23,7 @@
import threading
except ImportError:
import dummy_threading as threading
+ self.maxsize = maxsize
self._init(maxsize)
# mutex must be held whenever the queue is mutating. All methods
# that acquire mutex must release it before returning. mutex
@@ -91,14 +92,14 @@
def empty(self):
"""Return True if the queue is empty, False otherwise (not reliable!)."""
self.mutex.acquire()
- n = self._empty()
+ n = not self._qsize()
self.mutex.release()
return n
def full(self):
"""Return True if the queue is full, False otherwise (not reliable!)."""
self.mutex.acquire()
- n = self._full()
+ n = 0 < self.maxsize == self._qsize()
self.mutex.release()
return n
@@ -115,21 +116,22 @@
"""
self.not_full.acquire()
try:
- if not block:
- if self._full():
- raise Full
- elif timeout is None:
- while self._full():
- self.not_full.wait()
- else:
- if timeout < 0:
- raise ValueError("'timeout' must be a positive number")
- endtime = _time() + timeout
- while self._full():
- remaining = endtime - _time()
- if remaining <= 0.0:
+ if self.maxsize > 0:
+ if not block:
+ if self._qsize() == self.maxsize:
raise Full
- self.not_full.wait(remaining)
+ elif timeout is None:
+ while self._qsize() == self.maxsize:
+ self.not_full.wait()
+ elif timeout < 0:
+ raise ValueError("'timeout' must be a positive number")
+ else:
+ endtime = _time() + timeout
+ while self._qsize() == self.maxsize:
+ remaining = endtime - _time()
+ if remaining <= 0.0:
+ raise Full
+ self.not_full.wait(remaining)
self._put(item)
self.unfinished_tasks += 1
self.not_empty.notify()
@@ -158,16 +160,16 @@
self.not_empty.acquire()
try:
if not block:
- if self._empty():
+ if not self._qsize():
raise Empty
elif timeout is None:
- while self._empty():
+ while not self._qsize():
self.not_empty.wait()
+ elif timeout < 0:
+ raise ValueError("'timeout' must be a positive number")
else:
- if timeout < 0:
- raise ValueError("'timeout' must be a positive number")
endtime = _time() + timeout
- while self._empty():
+ while not self._qsize():
remaining = endtime - _time()
if remaining <= 0.0:
raise Empty
@@ -192,20 +194,11 @@
# Initialize the queue representation
def _init(self, maxsize):
- self.maxsize = maxsize
self.queue = deque()
def _qsize(self):
return len(self.queue)
- # Check whether the queue is empty
- def _empty(self):
- return not self.queue
-
- # Check whether the queue is full
- def _full(self):
- return self.maxsize > 0 and len(self.queue) == self.maxsize
-
# Put a new item in the queue
def _put(self, item):
self.queue.append(item)