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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: [Off-Topic] Python gets :=
Date: Sat, 21 Jul 2018 09:34:32 -0700
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Date: 2018-07-21T09:34:32-07:00
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Rene <rehartmann@t-online.de> writes:
> So it would more logical the other way round: = for assignment
> expression and := for assignment. But of course this is not possible
> because of backwards compatibility.

In principle it's fine to use the same symbol for both.  GvR picked =
for assignment, and then didn't want to use it for assignment
expressions because of the possible bug where someone says "if a=b"
(assignment) when they meant "if a==b" (comparison).  So he decided to
not have assignment expressions at all.  That lack was a source of 20
years of conflict in the Python community.  Finally he accepted the :=
proposal and that set off enough conflict in its own right, that he
stepped down as BDFL (leader) of Python.