On Sat, 31 Dec 2005 [EMAIL PROTECTED] wrote:
> just> I actually prefer such a global variable to the default arg
> just> trick. The idiom I generally use is:
>
> just> _cache = {}
> just> def func(x):
> just> result = _cache.get(x)
> just> if result is None:
> just> result = x + 1 # or a time consuming calculation...
> just> _cache[x] = result
> just> return result
>
> None of the responses I've seen mention the use of decorators such as the
> one shown here:
>
> http://wiki.python.org/moin/PythonDecoratorLibrary
>
> While wrapping one function in another is obviously a bit slower, you can
> memoize any function without tweaking its source.
I'd definitely say this is the way to go.
def memoised(fn):
cache = {}
def memoised_fn(*args):
if args in cache:
return cache[args]
else:
rtn = fn(*args)
cache[args] = rtn
return rtn
return memoised_fn
@memoised
def func(x):
return x + 1 # or a time-consuming calculation
tom
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