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Re: ! function

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On 07/05/2015 07:15, Andrew Poulos wrote:
> I was looking at some "swipe" libraries when I happened upon hammer.js.
> <http://hammerjs.github.io/dist/hammer.min.js>
> 
> I've no idea yet as to its quality but the very first line begins with
> 
> ! function(a, b, c, d) {
> 
> What's the reason behind starting with an exclamation mark?


An Immediately-Invoked Function Expression (IIFE) is usually written as:
(function() { /* etc. */ })();

Or:

(function() { /* etc. */ }()); // Douglas Crockford's preference.

But we can use unary operators instead of the wrapping parentheses too,
if we don't care about the return value of the IIFE:

+function() { /*...*/ }();
!function() { /*...*/ }();
-function() { /*...*/ }();
~function() { /*...*/ }();

Even the void operator can be used:
void function () { /*...*/ }();

-- 
Joao Rodrigues

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Thread

! function Andrew Poulos <ap_prog@hotmail.com> - 2015-05-07 20:15 +1000
  Re: ! function "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-07 13:04 +0200
  Re: ! function "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2015-05-07 05:02 -0700
  Re: ! function Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-05-07 12:27 -0300
    Re: ! function JJ <jj4public@vfemail.net> - 2015-05-08 00:09 +0700
    Re: ! function "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-07 21:07 +0200
      Re: ! function "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-05-07 21:31 +0200
        Re: ! function "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-07 22:20 +0200
          Re: ! function "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-05-07 23:27 +0200
            Re: ! function "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-05-08 00:26 +0200
              Re: ! function "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-08 11:00 +0200
                Re: ! function James Lewis <lewisje@gmail.com> - 2015-06-05 09:10 -0700
          Re: ! function Scott Sauyet <scott.sauyet@gmail.com> - 2015-05-18 13:31 -0700
            Re: ! function "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-05-19 01:39 +0200
              Re: ! function Scott Sauyet <scott.sauyet@gmail.com> - 2015-05-19 05:48 -0700
        Re: ! function Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-05-07 17:47 -0300
          Re: ! function "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-07 23:22 +0200
            Re: ! function Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-05-07 19:08 -0300
              Re: ! function "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-08 12:08 +0200

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