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Re: Remove leading zeros in index of array

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jonas.thornvall@gmail.com wrote:
> jonas.thornvall@gmail.com wrote:
>> I store integers in the indexes of an array, is there a prefared 
>> or easy way to remove all leading indexes  containing zeros?
>> [ ... ] 
> This is what i've come up with.
> 
> while (result[length]==0)  {result.splice(length, 1);length+=-1;}

One possibility:

    var removeLeadingZeros = function(list) {
      var firstNonZero = 0;
      list.every(function(item, index) {
        if (item !== 0) {
          firstNonZero = index;
          return false;
        }
        return true;
      });
      return list.slice(firstNonZero);
    };

This depends on `Array.prototype.every` which is not available in JScript
before Chakra (i.e. before IE9), and would have to be polyfilled if you
wanted to use it in that environment.

While it's not a beautiful solution, it certainly seems better than
continually `splice`ing out values.  Note that this does *not* modify your
original list but returns a copy of it.  To my mind this is an advantage;
but if you prefer, you could always replace that last line with a single 
`splice` call.

  -- Scott

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Remove leading zeros in index of array jonas.thornvall@gmail.com - 2015-03-23 04:57 -0700
  Re: Remove leading zeros in index of array jonas.thornvall@gmail.com - 2015-03-23 10:03 -0700
    Re: Remove leading zeros in index of array Scott Sauyet <scott.sauyet@gmail.com> - 2015-03-23 10:32 -0700
    Re: Remove leading zeros in index of array Tim Streater <timstreater@greenbee.net> - 2015-03-23 18:36 +0000
    Re: Remove leading zeros in index of array "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-03-23 20:42 +0100
      Re: Remove leading zeros in index of array jonas.thornvall@gmail.com - 2015-03-23 12:58 -0700
        Re: Remove leading zeros in index of array "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-03-23 21:12 +0100
          Re: Remove leading zeros in index of array jonas.thornvall@gmail.com - 2015-03-23 13:16 -0700
            Re: Remove leading zeros in index of array "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-03-23 21:36 +0100
              Re: Remove leading zeros in index of array "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-03-23 21:49 +0100
                Re: Remove leading zeros in index of array "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-03-23 21:58 +0100
  Re: Remove leading zeros in index of array Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2015-03-24 15:41 +0100
    Re: Remove leading zeros in index of array Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-03-24 20:21 +0100
      Re: Remove leading zeros in index of array Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2015-03-24 20:45 +0100
        Re: Remove leading zeros in index of array Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-03-24 20:47 +0100
    Re: Remove leading zeros in index of array Scott Sauyet <scott.sauyet@gmail.com> - 2015-03-24 13:37 -0700
      Re: Remove leading zeros in index of array Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2015-03-25 00:01 +0100

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