Re: Proposal for new minor syntax

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From	Ian Kelly <ian.g.kelly@gmail.com>
Date	Sat, 28 Mar 2015 22:15:53 -0600
Subject	Re: Proposal for new minor syntax
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On Sat, Mar 28, 2015 at 9:05 AM, Mario Figueiredo <marfig@gmail.com> wrote:
> Neiter the language. The dot symbol is a delimiter in the python
> grammar. Not an operator. And also defined as a delimiter in the
> official documentation, right after operators.

What does it matter? How '.' is lexed when it appears on its own
should make no difference to the lexing of '.='.

> Meanwhile augmented assignment is governed by the `augassign`
> nonterminal. An addition to its list would result in a non backwards
> compatible new syntactic sugar feature. This would mabe not be a big
> issue between 3.X and 2.X, but would, I reckon, be against the
> compatibility rules between 3.X versions.

How would it not be backwards compatible? I'm not able to come up with
any situation where the character sequence '.=' is currently legal
outside of string literals and comments.

The counter-proposed '=.' could be an issue, since this is currently
legal Python:

    x=.3

But I believe even that is still unambiguous since you couldn't
currently follow the =. with an identifier.

Thread

Re: Proposal for new minor syntax Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-27 14:48 -0600
  Re: Proposal for new minor syntax BartC <bc@freeuk.com> - 2015-03-27 23:08 +0000
    Re: Proposal for new minor syntax Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-28 20:53 +1100
      Re: Proposal for new minor syntax Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-28 21:43 +1100
        Re: Proposal for new minor syntax Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2015-04-09 09:32 +0200
      Re: Proposal for new minor syntax BartC <bc@freeuk.com> - 2015-03-28 13:38 +0000
        Re: Proposal for new minor syntax Mario Figueiredo <marfig@gmail.com> - 2015-03-28 16:05 +0100
          Re: Proposal for new minor syntax Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-28 22:15 -0600
            Re: Proposal for new minor syntax Rustom Mody <rustompmody@gmail.com> - 2015-03-28 21:50 -0700
  Re: Proposal for new minor syntax Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-28 21:01 +1100

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