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jquery-element-class (v2)

Revision 2 of this benchmark created on September 29, 2011

Description

Determine whether or not prefacing a class-name with an element name achieves any performance boost with jQuery selectors.

Hypothesis: like in CSS, adding an element name to the class name will not provide any performance boost, because selectors are evaluated right-to-left. Also, pseudo-selectors are slow.

Preparation HTML

<script src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js">
</script>
<div class="visible">
  <p>
    Shown
  </p>
</div>

Test runner

Ready to run.

Testing in
Test		Ops/sec
Selector Plus Class	`$("div.visible").hide();`	ready
Class Only	`$(".visible").hide();`	ready
Pseudo Class	`$(".visible:visible").hide();`	ready
.is(':visible')	`var d = $(".visible"); if (d.is(":visible")) { d.hide(); }`	ready

Revisions

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

Revision 1: published by Joshua Cody on September 29, 2011
Revision 2: published on September 29, 2011