Python Conditional “With” Lock Design

Just use a threading.RLock which is re-entrant meaning it can be acquired multiple times by the same thread.

http://docs.python.org/library/threading.html#rlock-objects

For clarity, the RLock is used in the with statements, just like in your sample code:

lock = threading.RLock()

def func1():
    with lock:
        func2()

def func2():
    with lock: # this does not block even though the lock is acquired already
        print 'hello world'

As far as whether or not this is bad design, we’d need more context. Why both of the functions need to acquire the lock? When is func2 called by something other than func1?

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