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Re: Static caching property

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From "Joseph L. Casale" <jcasale@activenetwerx.com>
Newsgroups comp.lang.python
Subject Re: Static caching property
Date Mon, 21 Mar 2016 17:03:49 +0000
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> One solution is to use descriptor protocol on the class, which means
> using a metaclass. I'm not sure it's the best option, but it is an
> option.

I will look at that, I wonder if however I am not over complicating it:

class Foo:
    _bar = None
    @property
    def expensive(self):
        if Foo._bar is None:
            import something
            Foo._bar = something.expensive()
        return Foo._bar

Somewhat naive, but a test with if is pretty cheap...
Thanks Chris,
jlc

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Thread

Re: Static caching property Ian Kelly <ian.g.kelly@gmail.com> - 2016-03-21 10:15 -0600
  Re: Static caching property Steven D'Aprano <steve@pearwood.info> - 2016-03-22 03:36 +1100
    Re: Static caching property "Joseph L. Casale" <jcasale@activenetwerx.com> - 2016-03-21 16:49 +0000
    Re: Static caching property Chris Angelico <rosuav@gmail.com> - 2016-03-22 03:54 +1100
    Re: Static caching property "Joseph L. Casale" <jcasale@activenetwerx.com> - 2016-03-21 17:03 +0000
    Re: Static caching property Ian Kelly <ian.g.kelly@gmail.com> - 2016-03-21 11:44 -0600
    Re: Static caching property Ethan Furman <ethan@stoneleaf.us> - 2016-03-21 10:45 -0700
    Re: Static caching property Ian Kelly <ian.g.kelly@gmail.com> - 2016-03-21 11:48 -0600
      Re: Static caching property Steven D'Aprano <steve@pearwood.info> - 2016-03-22 11:05 +1100
        Re: Static caching property Chris Angelico <rosuav@gmail.com> - 2016-03-22 11:15 +1100
        Re: Static caching property Ian Kelly <ian.g.kelly@gmail.com> - 2016-03-22 07:30 -0600

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