jQuery xpath
document.evaluate() (DOM Level 3 XPath) is supported in Firefox, Chrome, Safari and Opera - the only major browser missing is MSIE. Nevertheless, jQuery supports basic XPath expressions: http://docs.jquery.com/DOM/Traversing/Selectors#XPath_Selectors (moved into a plugin in the current jQuery version, see https://plugins.jquery.com/xpath/). It simply converts XPath expressions into equivalent CSS selectors however.
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