New GitHub issue #92203 from larryhastings:<br>
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**Feature or enhancement**
`exec()` can run either a string or a code object. Usually the code object run in `exec()` is produced directly using `compile()`. But it's completely fine to pull the code object out of a function object and execute it with `exec()`. This can be useful if you want to run the code object in some exotic environment, e.g. with a modified `globals`.
Some code objects refer to free variables, and can only run when a closure is set. Currently, `exec()` simply rejects these code objects--you aren't permitted to use them with `exec()`, it throws an exception if you try.
It's possible to work around this limitation. Instead of using `exec()`, one could simply bind a new function using the code object and whatever closure or globals you wanted. But this seems like an unnecessary limitation on the functionality of `exec()`.
I propose to add a *closure* keyword-only argument to `eval()`. It can only be specified if the code object uses free variables. When specified, it must be a tuple, with exactly the number of cell variables referenced by the code object. *closure* has a default value of `None`, and it must be `None` if the code object doesn't refer to any free variables.
We do have a use case for this, in conjunction with PEP 649. Carl Meyer proposes to pull the code object out of a co_annotations function, and run it with a globals object that enables us to handle undefined (forward-defined) names.
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<a href="https://github.com/python/cpython/issues/92203">View on GitHub</a>
<p>Labels: type-feature</p>
<p>Assignee: </p>