jQuery to find all previous elements that match an expression

Question

Using jQuery, how do you match elements that are prior to the current element in the DOM tree? Using prevAll() only matches previous siblings.<

Answer 1

I usually number elements (1,2,3..) (rel="number"), so then i use this code to give class to all previous elements:

var num = $(this).attr("rel");

for (var i = 1; i<=num; i++)
{
    $('.class[rel="'+i+'"]').addClass("newclass");
}