Re: Why does (a,b,c) return only c?

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From	"Christoph M. Becker" <cmbecker69@arcor.de>
Newsgroups	comp.lang.javascript
Subject	Re: Why does (a,b,c) return only c?
Date	Mon, 25 May 2015 14:57:50 +0200
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Evertjan. wrote:

> Steven D'Aprano <steve@pearwood.info> wrote on 25 mei 2015 in 
> comp.lang.javascript:
> 
>> Consider:
>>
>> js> var x = (1,2,3);
>> js> x
>> 3

Because ECMAScript implementations don't have a tuple type like Python has.

> So it seems just a set of statements executed in line,
> the result value of the last one returned.

See <http://www.ecma-international.org/ecma-262/5.1/#sec-11.14> for details.

> However this errors:
> 
> (var i=4,++i,i=i*10,a=7,-3,i++);
> 
> Why?

A variable statement is not allowed in an expression, see
<http://www.ecma-international.org/ecma-262/5.1/#sec-11.1>.

-- 
Christoph M. Becker

Thread

Why does (a,b,c) return only c? Steven D'Aprano <steve@pearwood.info> - 2015-05-25 21:43 +1000
  Re: Why does (a,b,c) return only c? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-25 14:17 +0200
    Re: Why does (a,b,c) return only c? Luuk <luuk@invalid.lan> - 2015-05-25 14:42 +0200
      Re: Why does (a,b,c) return only c? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-25 14:58 +0200
    Re: Why does (a,b,c) return only c? "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-05-25 14:57 +0200
      Re: Why does (a,b,c) return only c? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-25 15:07 +0200
        Re: Why does (a,b,c) return only c? "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-05-25 15:32 +0200
          Re: Why does (a,b,c) return only c? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-25 17:50 +0200
        Re: Why does (a,b,c) return only c? Luuk <luuk@invalid.lan> - 2015-05-25 19:53 +0200
          Re: Why does (a,b,c) return only c? "D. Aaron Sawyer" <aaron@110.net> - 2015-05-25 19:49 -0300
  Re: Why does (a,b,c) return only c? John-Paul Stewart <jpstewart@sympatico.ca> - 2015-05-25 13:58 -0400
    Re: Why does (a,b,c) return only c? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-25 21:57 +0200
      Re: Why does (a,b,c) return only c? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-05-25 19:24 -0300
        Re: Why does (a,b,c) return only c? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-05-26 12:26 +0200
          Re: Why does (a,b,c) return only c? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-05-26 09:36 -0300
            Re: Why does (a,b,c) return only c? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-05-26 14:42 +0200
              Re: Why does (a,b,c) return only c? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-05-26 09:53 -0300
                Re: Why does (a,b,c) return only c? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-26 15:15 +0200
                Re: Why does (a,b,c) return only c? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-05-26 15:17 +0200
          Re: Why does (a,b,c) return only c? Scott Sauyet <scott.sauyet@gmail.com> - 2015-05-26 08:59 -0700

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