[Python-Dev] Removing callable() from the stdlib

[Collin Winter]

On Fri, Mar 28, 2008 at 12:58 PM, Guido van Rossum <guido at python.org> wrote:
>
> On Fri, Mar 28, 2008 at 10:51 AM, Collin Winter <collinw at gmail.com> wrote:
>  > I've been running 2to3's fix_callable over 2.6's stdlib to remove -3
>  >  warnings due to callable() usage; 2to3 replaces callable(x) with
>  >  has_attr(x, "__call__"). Unfortunately, this breaks code that wants to
>  >  run callable() on old-style classes (like test_builtin), because
>  >  old-style classes don't have a __call__ attribute (new-style classes
>  >  do, however).
>  >
>  >  How should this be handled? I'm tempted to just add __call__ to
>  >  old-style classes for 2.6, but Neal Norwitz thought that might break
>  >  some user code. Any other thoughts?
>
>  I don't see how this would break user code, as long as the __call__
>  shows up for the *class* but not for the *instance*, and as long as it
>  doesn't break users overriding __call__ in a classic class to make the
>  instances callable.

Yep, I was only going to make it appear on the class. I'll go ahead
and whip up a patch.

Collin