[Python-Dev] Arbitrary non-identifier string keys when using **kwargs

[Benjamin Peterson]

On Tue, Oct 9, 2018, at 17:14, Barry Warsaw wrote:
> On Oct 9, 2018, at 16:21, Steven D'Aprano <steve at pearwood.info> wrote:
> > 
> > On Tue, Oct 09, 2018 at 10:26:50AM -0700, Guido van Rossum wrote:
> >> My feeling is that limiting it to strings is fine, but checking those
> >> strings for resembling identifiers is pointless and wasteful.
> > 
> > Sure. The question is, do we have to support uses where people
> > intentionally smuggle non-identifier strings as keys via **kwargs?
> 
> I would not be in favor of that.  I think it doesn’t make sense to be 
> able to smuggle those in via **kwargs when it’s not supported by 
> Python’s grammar/syntax.

Can anyone think of a situation where it would be advantageous for an implementation to reject non-identifier string kwargs? I can't.

I agree with Guido—banning it would be too much trouble for no benefit.