Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Random832 <random832@fastmail.com>
Newsgroups: comp.lang.python
Subject: Re: Question about math.pi is mutable
Date: Mon, 09 Nov 2015 10:32:17 -0500
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Steven D'Aprano <steve@pearwood.info> writes:
> The compiler doesn't need to decide in advance whether or not the module
> attributes have been changed. It can decide that at runtime, just before
> actually looking up the attribute. In pseudo-code:
>
>     if attribute might have changed:
>         use the slow path just like today
>     else:
>         use the optimized fast path


if attribute might have changed:
   check if attribute really did change
   if it didn't:
      reset means of determining if it might have changed
      goto the optimized fast path
   else:
      use the slow path and/or maybe make a new fast path
else:
   use the optimized fast path

And what if your optimization depends on _two_ things that might change?
Do you create one really fast path and two sort of fast paths?