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Swap Strings Split Versus Substring Versus Temp Var

Benchmark created by Noah Feldman on July 18, 2011

Preparation HTML

<script>
  var str1 = 'Saturday', str2 = 'Sunday';
</script>

Test runner

Ready to run.

Testing in
Test		Ops/sec
Concat and Split	`str1 = str2 + str1; str2 = str1.split(str2)[1]; str1 = str1.split(str2)[0];`	ready
Concat and Sub	`str1 = str2 + str1; str2 = str1.substring(0, str2.length - str1.length); str1 = str1.substring(0, str1.length - str2.length);`	ready
Swap Variable	`var temp = str1; str1 = str2; str2 = temp;`	ready
JavaScript 1.7 only	`[str1,str2] = [str2,str1]; // will fail in !Gecko`	ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

Revision 1: published by Noah Feldman on July 18, 2011