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Re: silly question on closure

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On 2012-09-22 14:04, justaguy wrote:
> Code:
[snipped]

> Question:
> The closure takes so many lines while the function has only 2 lines to
> get the same thing done.  So, the question is, why do we use closure?

You don't, just like you don't actually use "Hello, world" in production
code. This was obviously just an example for how closures work. If this
was code intended for actual use, your "just a function" variant would
be better suited (provided it only returned the value, like in the
"closure" example).

One case where the closure variant would be preferred is if the contents
of then "names" array would take a long time to compute, or if they were
fetched from a remote source.

> Could you elaborate a bit with a practical example?

Counters are popular examples for simple closures:

    var sequence = (function () {

        var value = 0;

        return function () {
            ++value;
            return value;
        };

    })();

    alert(sequence()); // 1
    alert(sequence()); // 2
    alert(sequence()); // 3

- stefan

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silly question on closure justaguy <lichunshen84@gmail.com> - 2012-09-22 05:04 -0700
  Re: silly question on closure Stefan Weiss <krewecherl@gmail.com> - 2012-09-22 18:18 +0200
    Re: silly question on closure justaguy <lichunshen84@gmail.com> - 2012-09-22 18:41 -0700
    Re: silly question on closure Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-09-24 01:10 +0200
      Closures (was: silly question on closure) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-09-24 13:14 +0200
      Re: silly question on closure Stefan Weiss <krewecherl@gmail.com> - 2012-09-27 05:04 +0200
        Re: silly question on closure Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-09-27 20:50 +0200
          Re: silly question on closure Stefan Weiss <krewecherl@gmail.com> - 2012-09-27 21:29 +0200
  Re: silly question on closure "Tom de Neef" <tdeneef@qolor.nl> - 2012-09-22 20:00 +0200
    Re: silly question on closure justaguy <lichunshen84@gmail.com> - 2012-09-22 18:42 -0700
      Re: silly question on closure justaguy <lichunshen84@gmail.com> - 2012-09-23 07:31 -0700
        Re: silly question on closure Stefan Weiss <krewecherl@gmail.com> - 2012-09-23 18:49 +0200
          Re: silly question on closure justaguy <lichunshen84@gmail.com> - 2012-09-23 13:33 -0700
          Re: silly question on closure justaguy <lichunshen84@gmail.com> - 2012-09-23 13:38 -0700
            Re: silly question on closure Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-09-24 20:49 +0200
    Re: silly question on closure Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-09-24 01:14 +0200
  Re: silly question on closure dann90038@gmail.com - 2012-09-23 15:37 -0700

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