Code: Alles auswählen
"""The synchronized Queue from the standard lib with a peek method"""
import Queue
class PQueue(Queue.Queue):
def peek(self):
if self._empty():
raise Queue.Empty
return self.queue[0]
Ja!Jona hat geschrieben:oder muss ich mich hier um die locks kümmern?
Code: Alles auswählen
"""The synchronized Queue from the standard lib with a peek method"""
import Queue
class PQueue(Queue.Queue):
def peek(self, block=True, timeout=None):
"""Return but do not remove an item from the queue.
If optional args 'block' is true and 'timeout' is None (the default),
block if necessary until an item is available. If 'timeout' is
a positive number, it blocks at most 'timeout' seconds and raises
the Empty exception if no item was available within that time.
Otherwise ('block' is false), return an item if one is immediately
available, else raise the Empty exception ('timeout' is ignored
in that case).
"""
self.not_empty.acquire()
try:
if not block:
if self._empty():
raise Empty
elif timeout is None:
while self._empty():
self.not_empty.wait()
else:
if timeout < 0:
raise ValueError("'timeout' must be a positive number")
endtime = _time() + timeout
while self._empty():
remaining = endtime - _time()
if remaining <= 0.0:
raise Empty
self.not_empty.wait(remaining)
item = self._peek()
self.not_full.notify()
return item
finally:
self.not_empty.release()
def _peek(self):
return self.queue[0]
Code: Alles auswählen
if q.peek() == x:
return q.get()
