Question

what is the best way to find first element in the html document with the class myClass with position top greater than specified

Answer 1

Wrong (first answer) :

var $elm = jQuery.each($('.myClass'), function() {
    if ($(this).attr('top') > x) return $(this); 
});

Ok :

var $elm;
jQuery.each($('.myClass'), function() {
    if ($(this).attr('top') > x) {
        $elm = $(this);
        return false;
    }
});

This solution does not parse all .myClass elements, just returns the first one and stops.