Re: is there a function enumerating all element in an object?

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From	Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups	comp.lang.javascript
Subject	Re: is there a function enumerating all element in an object?
Date	Thu, 29 Oct 2015 20:49:25 +0000
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"Evertjan." <exxjxw.hannivoort@inter.nl.net> writes:

> Joao Rodrigues <groups_jr-1@yahoo.com.br> wrote on 29 Oct 2015 in 
> comp.lang.javascript:
>
>>> Object.keys(obj).map(key => callback(key, obj[key]));
>> Or:
>> 
>> Array.from(Object.keys(obj), key => callback(key, obj[key]));
>
> Could you please explain to us simple minded how this realy works?

In ES6, the form

  x => expression

is similar to

  function (x) { return expression; }

There are a few differences ("this" is lexical in an arrow function and
there is no "arguments" object) but neither of those matter here I don't
think.

[You may have multiple parameters:

  (a, b) => a + b

and you may have an explicit block rather than a single expression:

  x => { console.log(`x = ${x}`); return x; }

which sneaks in another ES6 feature: template strings.]

-- 
Ben.

Thread

is there a function enumerating all element in an object? Stone Zhong <stone.zhong@gmail.com> - 2015-08-21 22:44 -0700
  Re: is there a function enumerating all element in an object? nathank887@gmail.com - 2015-10-28 22:11 -0700
    Re: is there a function enumerating all element in an object? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-10-29 15:59 -0200
      Re: is there a function enumerating all element in an object? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-10-29 16:20 -0200
        Re: is there a function enumerating all element in an object? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-10-29 20:58 +0100
          Re: is there a function enumerating all element in an object? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-29 20:49 +0000
            Re: is there a function enumerating all element in an object? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-10-29 22:49 +0100
              Re: is there a function enumerating all element in an object? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-10-30 16:05 -0200
              Re: is there a function enumerating all element in an object? RobG <rgqld@iinet.net.au> - 2015-11-14 13:16 -0800
                Re: is there a function enumerating all element in an object? Chuck Anderson <seemysig@thisis.invalid> - 2015-11-14 17:58 -0700
                Re: is there a function enumerating all element in an object? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-11-16 14:26 -0200
  Re: is there a function enumerating all element in an object? donmaximo01@gmail.com - 2015-10-29 06:08 -0700

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