On 30 Apr 2009, at 12:22, Scott David Daniels wrote:
This is slightly better (name change as in Antoine Pitrou's comment):
class cached(object):
def __init__(self, function): self._function = function self._cache = {}
def __call__(self, *args): try: return self._cache[args] except KeyError: self._cache[args] = self._function(*args) return self._cache[args]
def expire(self, *args): del self._cache[args]
The only thing I dislike is how many dictionary lookups are required in order to return the value after it's been cached. I count 4 lookups (object.prop, prop.__call__, self._cache, and self._cache[args]). These add up, especially if object.prop could have returned the value immediately without having to go through so much indirection (but this is not currently possible) Jared