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Re: Decorators not worth the effort

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I think one very nice and simple example of how decorators can be used is this:

def memoize(f, cache={}, *args, **kwargs):
    def _memoize(*args, **kwargs):
        key = (args, str(kwargs))
        if not key in cache:
            cache[key] = f(*args, **kwargs)

        return cache[key]

    return _memoize

def fib(n):
    if n <= 1:
        return 1
    return fib(n-1) + fib(n-2)

@memoize
def fib_memoized(n):
    if n <= 1:
        return 1
    return fib_memoized(n-1) + fib_memoized(n-2)


The second fibonacci looks exactly the same but while the first is
very slow and would generate a stack overflow the second doesn't..

I might use this example for the presentation, before explaining what it is..

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Re: Decorators not worth the effort Jean-Michel Pichavant <jeanmichel@sequans.com> - 2012-09-14 11:28 +0200
  Re: Decorators not worth the effort Duncan Booth <duncan.booth@invalid.invalid> - 2012-09-14 11:26 +0000
    Re: Decorators not worth the effort andrea crotti <andrea.crotti.0@gmail.com> - 2012-09-14 15:12 +0100
    Re: Decorators not worth the effort Chris Angelico <rosuav@gmail.com> - 2012-09-15 00:41 +1000
      Re: Decorators not worth the effort 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-14 09:37 -0700
      Re: Decorators not worth the effort 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-14 09:37 -0700
    Re: Decorators not worth the effort andrea crotti <andrea.crotti.0@gmail.com> - 2012-09-14 17:15 +0100
    Re: Decorators not worth the effort Chris Angelico <rosuav@gmail.com> - 2012-09-15 03:30 +1000
      Re: Decorators not worth the effort Neil Cerutti <neilc@norwich.edu> - 2012-09-18 13:19 +0000
        Re: Decorators not worth the effort Chris Angelico <rosuav@gmail.com> - 2012-09-18 23:25 +1000
          Re: Decorators not worth the effort 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-18 08:14 -0700
          Re: Decorators not worth the effort 88888 Dihedral <dihedral88888@googlemail.com> - 2012-09-18 08:14 -0700
    RE: Decorators not worth the effort "Prasad, Ramit" <ramit.prasad@jpmorgan.com> - 2012-09-14 23:14 +0000
  Re: Decorators not worth the effort Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-14 12:01 +0000
    Re: Decorators not worth the effort Tim Chase <python.list@tim.thechases.com> - 2012-09-14 08:06 -0500
      Re: Decorators not worth the effort Steve Howell <showell30@yahoo.com> - 2012-09-14 18:13 -0700
  Re: Decorators not worth the effort Ulrich Eckhardt <ulrich.eckhardt@dominolaser.com> - 2012-09-14 13:49 +0200

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