30 lines
1,018 B
Python
30 lines
1,018 B
Python
# -*- coding: iso-8859-1 -*-
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# Copyright (C) 2012-2013 Bastian Kleineidam
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class memoized (object):
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"""Decorator that caches a function's return value each time it is called.
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If called later with the same arguments, the cached value is returned, and
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not re-evaluated."""
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def __init__(self, func):
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"""Store function and initialize the cache."""
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self.func = func
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self.cache = {}
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def __call__(self, *args):
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"""Lookup and return cached result if found. Else call stored
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function with given arguments."""
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try:
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return self.cache[args]
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except KeyError:
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self.cache[args] = value = self.func(*args)
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return value
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except TypeError:
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# uncachable -- for instance, passing a list as an argument.
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# Better to not cache than to blow up entirely.
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return self.func(*args)
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def __repr__(self):
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"""Return the function's docstring."""
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return self.func.__doc__
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