jQuery plugin to toggle an element's classes based on a prefix.

jquery.toggleClassPrefix.js

/**
 * Toggles the CSS classes of an element based on a prefix::
 *   > elems = $(".status")
 *   > elems
 *   [<div class="status status-active">, <div class="status status-pending">]
 *   > elems.toggleClassPrefix("status-", "status-pending")
 *   > elems
 *   [<div class="status status-pending">, <div class="status status-pending">]
 */
$.fn.toggleClassPrefix = function(prefix, toAdd) {
  $(this).each(function() {
    var newClass = $.grep(this.classList, function(cls) {
      return cls.indexOf(prefix) != 0;
    });
    newClass.push(toAdd);
    this.className = newClass.join(" ");
  });
  return this;
}