46 lines
842 B
HTML
46 lines
842 B
HTML
<script type="text/javascript">
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(function(){
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// Conclusion: slice is a little faster except on Chrome
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// clone() is slower on FF & IE but takes 50% on Safari & Chrome
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var SIZE = 1e4,
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LOOPS = 500;
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var arr = new Array(SIZE);
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for ( var i=arr.length-1; i >= 0; --i )
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arr[i] = 0;
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var t = new Date;
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for ( i=0; i < LOOPS; i++ )
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arr.slice(0);
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var tslice = new Date - t;
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t = new Date;
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for ( i=0; i < LOOPS; i++ )
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arr.concat();
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var tconcat = new Date - t;
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// clone() is just to see how fast built-ins are
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t = new Date;
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for ( i=0; i < LOOPS; i++ )
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clone(arr);
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var tclone = new Date - t;
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alert([
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'slice:'+tslice,
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'concat:'+tconcat,
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'clone:'+tclone
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].join('\n'));
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function clone(arr){
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var i = arr.length,
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copy = new Array(i);
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while (i--)
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copy[i] = arr[i];
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return copy;
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}
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})();
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</script> |