Info

Compare speeds of native array methods vs a while loop

Preparation code

 
<script>
  Benchmark.prototype.setup = function() {
    function spliceMap(length, fill){
        var a = [], b = [];
        a.length = length + 2;
            a[0] = 0; a[1] = 0;
        b.splice.apply(b,a);
        return b.map(function(){return fill;});
    }
    
    function pushMap(length, fill){
        var a = [], b = [];
        a.length = length;
        b.push.apply(b,a);
        return b.map(function(){return fill;});
    }
    
    function whileLengthNew(len, val) {
        var rv = new Array(len);
        while (--len >= 0) {
            rv[len] = val;
        }
        return rv;
    }
    
    function whileLengthLiteral(len, val) {
        var rv = [];
        while (--len >= 0) {
            rv[len] = val;
        }
        return rv;
    }
  };
</script>

Test runner

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Java applet disabled.

spliceMap(255,0);
spliceMap(255,true);

pushMap(255,0);
pushMap(255,true);

whileLengthLiteral(255,0);
whileLengthLiteral(255,true);

whileLengthNew(255,0);
whileLengthNew(255,true);

pushMap(65536,0);
pushMap(65536,true);

whileLengthNew(65536,0);
whileLengthNew(65536,true);

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

• Revision 1: published on 17th September 2012
• Revision 2: published on 17th September 2012
• Revision 3: published by Göran Andersson on 17th September 2012

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