[Python-ideas] Make "is" checks on non-singleton literals errors

[Raymond Hettinger]

On Oct 8, 2012, at 12:44 PM, Mike Graham <mikegraham at gmail.com> wrote:

> I regularly see learners using "is" to check for string equality and
> sometimes other equality. Due to optimizations, they often come away
> thinking it worked for them.
> 
> There are no cases where
> 
>    if x is "foo":
> 
> or
> 
>   if x is 4:
> 
> is actually the code someone intended to write.
> 
> Although this has no benefit to anyone but new learners, it also
> doesn't really do any harm.

This seems like a job for pyflakes, pylint, or pychecker.


Raymond