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POHow to make built-in containers (sets, dicts, lists) thread safe?
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copied!<p>I understand <a href="https://stackoverflow.com/questions/2227169/are-python-built-in-containers-thread-safe">from this question</a> that if I want to have a <code>set</code> which is thread-safe I have to implement the thread-safety part on my own.</p> <p>Therefore I could come up with:</p> <pre><code>from threading import Lock class LockedSet(set): """A set where add() and remove() are thread-safe""" def __init__(self, *args, **kwargs): # Create a lock self._lock = Lock() # Call the original __init__ super(LockedSet, self).__init__(*args, **kwargs) def add(self, elem): self._lock.acquire() try: super(LockedSet, self).add(elem) finally: self._lock.release() def remove(self, elem): self._lock.acquire() try: super(LockedSet, self).remove(elem) finally: self._lock.release() </code></pre> <p>So, of course only add() and remove() are thread-safe in this implementation. The other methods are not because they were not overwritten in the subclass.</p> <p>Now, the pattern is pretty simple: acquire lock, call original method, release lock. If I follow the logic above, I would have to overwrite all methods exposed by <code>set</code> in essentially the same way, e.g.:</p> <p>(pseudo-code)</p> <pre><code>def <method>(<args>): 1. acquire lock 2. try: 3. call original method passing <args> 4. finally: 5. release lock </code></pre> <p>(/pseudo-code)</p> <p>This is not only tedious but also prone to errors. So, any ideas/suggestions on how to approach this in a better way?</p>

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