Python lazy evaluator

Question

Is there a Pythonic way to encapsulate a lazy function call, whereby on first use of the function f(), it calls a previously bound function g(Z) an

Answer 1

Try using this decorator:

class Memoize:
    def __init__ (self, f):
        self.f = f
        self.mem = {}
    def __call__ (self, *args, **kwargs):
        if (args, str(kwargs)) in self.mem:
            return self.mem[args, str(kwargs)]
        else:
            tmp = self.f(*args, **kwargs)
            self.mem[args, str(kwargs)] = tmp
            return tmp

(extracted from dead link: http://snippets.dzone.com/posts/show/4840 / https://web.archive.org/web/20081026130601/http://snippets.dzone.com/posts/show/4840) (Found here: Is there a decorator to simply cache function return values? by Alex Martelli)

EDIT: Here's another in form of properties (using __get__) http://code.activestate.com/recipes/363602/