* Illustrate bug in functional.h

* style: pre-commit fixes

* Make functional casting more robust / add workaround

* Make function_record* casting even more robust

* See if this fixes PyPy issue

* It still fails on PyPy sadly

* Do not make new CTOR just yet

* Fix test

* Add name to ensure correctness

* style: pre-commit fixes

* Clean up tests + remove ifdef guards

* Add comments

* Improve comments, error handling, and safety

* Fix compile error

* Fix magic logic

* Extract helper function

* Fix func signature

* move to local internals

* style: pre-commit fixes

* Switch to simpler design

* style: pre-commit fixes

* Move to function_record

* style: pre-commit fixes

* Switch to internals, update tests and docs

* Fix lint

* Oops, forgot to resolve last comment

* Fix typo

* Update in response to comments

* Implement suggestion to improve test

* Update comment

* Simple fixes

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Aaron Gokaslan <aaronGokaslan@gmail.com>