DOM trav up stop specific class

by marcgrabow

HTML

<div class="row"></div><!-- should NOT count this row -->
<div class="row"><!-- should NOT count this row -->
    <div class="block"><!-- should stop here in traversing dom up -->
        <div class="row"></div><!-- should count this row -->
        <div class="row"></div><!-- should count this row -->
        <div id="current" class="row"></div>
        <div class="row"></div>
    </div>
</div>
<div class="row"></div><!-- should NOT count this row -->

JavaScript

var myStartElement = $('#current');
var previousRowCount = myStartElement.prevUntil('.block', '.row').length;
document.write(previousRowCount);