Allow eval and exec to take keyword arguments

[rtpg]

Feature or enhancement

Allow for globals and locals to be passed in as keyword arguments to exec and eval.

Pitch

exec and eval both can take globals and locals as positional arguments.
The built-in functions documentation shows the argument defaults, and every time I have the documentation open and am writing these, I default to keyword arguments, and it fails because the arguments are positional-only.

For functions like this that might only be present in a handful of places, kwargs give a good way to document what parameters each argument is referring to. I don't think that in a universe in which we were introducing eval/exec now that we would explicitly disallow kwargs.

Previous discussion

I sent this email to python-ideas

Extra Links

Here is an implementation, which just consists in changing the argument clinic config and rerunning. I set up some very basic kwarg tests mostly to test the case of "locals provided but globals not provided", but fortunately the existing implementations already handled this cleanly!

Linked PRs

• gh-105879: Add support for keyword arguments to eval and exec #105885

[sunmy2019]

My concern is, will this hurt performance a lot?

[JelleZijlstra]

We can benchmark it, but that seems unlikely; parsing code is probably a lot slower than accepting some keyword arguments.

[rtpg]

@sunmy2019 I added a link to a commit implementing this. The short version is eval now has a bit more parsing code, but exec already has support for one kwarg, so we're still looking at the same order of magnitude of instructions or existing code IMO.

[JelleZijlstra]

Make a PR :)

[rtpg]

Created the PR, and tests seem to be passing now

[JelleZijlstra]

This will be in Python 3.13, thank you!