[issue32690] Return function locals() in order of creation?

[Nick Coghlan]

Nick Coghlan <ncoghlan at gmail.com> added the comment:

The current oddity where the names will always appear in the reverse of declaration order comes from a C level loop in the frame object's "map_to_dict" helper function that loops in reverse [1]:

    ...
    for (j = nmap; --j >= 0; ) {
        ...
    }

While I haven't tried reversing that yet, I haven't found anything to indicate that it *needs* to be a reverse iteration - it looks like Guido just wrote it that way back in 1994 [2], and everyone that touched the code since then preserved the original iteration order since they didn't have a compelling reason to change it.


[1] https://github.com/python/cpython/blob/master/Objects/frameobject.c#L794
[2] https://github.com/python/cpython/commit/1d5735e84621a7fe68d361fa0e289fa2c3310836

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nosy: +ncoghlan

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