Author dabeaz
Recipients dabeaz, gvanrossum, ncoghlan, njs
Date 2018-01-28.10:34:43
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <1517135684.15.0.467229070634.issue32690@psf.upfronthosting.co.za>
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Some context:  I noticed this while discussing (in a course) a programming trick involving instance initialization and locals() that I'd encountered in the past:

    def _init(locs):
        self = locs.pop('self')
        for name, val in locs.items():
            setattr(self, name, val)

    class Spam:
        def __init__(self, a, b, c, d):
            _init(locals())

In looking at locals(), it was coming back in reverse order of method arguments (d, c, b, a, self).   To be honest, it wasn't a critical matter, but more of an odd curiosity in light of recent dictionary ordering.

I could imagine writing a slightly more general version of _init() that didn't depend on a named 'self' argument if order was preserved:

    def _init(locs):
       items = list(locs.items())
       _, self = items[0]
       for name, val in items[1:]:
           setattr(self, name, val)

Personally, I don't think the issue Nathaniel brings up is worth worrying about because it would be such a weird edge case on something that is already an edge case.  Returning variables in "lexical order"--meaning the order in which first encountered in the source seems pretty sensible to me.
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Date User Action Args
2018-01-28 10:34:44dabeazsetrecipients: + dabeaz, gvanrossum, ncoghlan, njs
2018-01-28 10:34:44dabeazsetmessageid: <1517135684.15.0.467229070634.issue32690@psf.upfronthosting.co.za>
2018-01-28 10:34:43dabeazlinkissue32690 messages
2018-01-28 10:34:43dabeazcreate