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Re: Static caching property

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From Chris Angelico <rosuav@gmail.com>
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Subject Re: Static caching property
Date Tue, 22 Mar 2016 03:54:32 +1100
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On Tue, Mar 22, 2016 at 3:49 AM, Joseph L. Casale
<jcasale@activenetwerx.com> wrote:
> Right, but _private refers to an api call that is expensive and may not even be accessed,
> so while I may new up three instances of Test across a, b and c, if none of those end up
> accessing var x, it shouldn't get fetched. Without some deferred execution, if the value
> of _private is a callable whose return value is what I am interested in, it gets invoked the
> moment the class is compiled.
>
> In the non static sense this is trivial to accomplish with the descriptor protocol, I am just not
> clear for the static sense.

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.

ChrisA

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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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