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[Python-Dev] Guarantee ordered dict literals in v3.7?

Stephen J. Turnbull turnbull.stephen.fw at u.tsukuba.ac.jp
Thu Dec 21 22:51:36 EST 2017 
Chris Barker writes:

 > Nathaniel Smith has pointed out that eval(pprint(a_dict)) is
 > supposed to return the same dict -- so documented behavior may
 > already be broken.

Sure, but that's because we put shoes on a snake.  Why anybody expects
no impediment to slithering, I don't know!

I understand the motivation to guarantee order, but it's a programmer
convenience that has nothing to do with the idea of mapping, and the
particular (insertion) order is very special and usually neither
relevant nor reproducible.  I have no problem whatsoever with just
documenting any failure to preserve order while reproducing dicts,
*except* that a process that inserts keys in the same order had better
result in the same insertion order.

Steve
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