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Singleton mode
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class Foo: pass
def
instance():
global inst
try:
inst
except:
inst =
Foo
()
return inst
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class
Singleton(object):
objs
= {}
def __new__(cls, *args, **kv):
if cls in cls.objs:
return cls.objs[cls]
cls.objs[cls] = object.__new__(cls)
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Singleton mode
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Singleton
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class
Singleton(object):
objs
= {}
objs_locker =
threading.Lock()
def __new__(cls, *args, **kv):
if cls in cls.objs:
return cls.objs[cls]
cls.objs_locker.acquire()
try:
if cls in cls.objs: ## double check
locking
return cls.objs[cls]
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