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[Python-Dev] assignment expressions: an alternative alternative proposal

Antoine Pitrou solipsis at pitrou.net
Tue Apr 24 18:16:04 EDT 2018 
On Tue, 24 Apr 2018 09:38:33 -0400
Yury Selivanov <yselivanov.ml at gmail.com> wrote:
> I propose to use the following syntax for assignment expressions:
> 
>     ( NAME = expr )
> 
> I know that it was proposed before and this idea was rejected, because
> accidentally using '=' in place of '==' is a pain point in
> C/C++/JavaScript.

To solve this issue, I would suggest another syntax:

    var NAME = expr

Strong points:
- the "var" keyword makes it clear that it's not a mistyped equality
  ("var NAME == expr" would be a syntax error)
- the "var" keyword can stand out thanks to syntax highlighting
- the "=" which traditionally spells assignement is there as well

Weak points:
- we need a deprecation cycle before "var" can be used as a keyword

(alternative keyword choices against "var": "using", "let", "bind"...)

Regards

Antoine.
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