A JS <a> and <li> switcher for WordPress menus

wp-menu-switch.js

/* MAIN MENU ITEM SWITCH
 *
 * Description:
 * For whatever reason, it's near impossible to get the WP markup in the menu to switch around
 * So we're begrudgingly doing it in JS
 * This is accomplished by using a regex that breaks the capture after each list item end tag
 *
 * Usage:
 * Really simple - just pass in the class / ID for the sidebar menu container
 * This function is not really reusable due to the regex but encapsulation is a good idea in a big JS file
 *
 * Params:
 * sidebarContainer - the ID/class of the sidebar menu container (jQuery selector, please include # or .)
 *
 */
function menuItemSwitch(sidebarContainer) {
  // 1- Get entire content of sidebar menu ul, then split by row
  var listItems = $(sidebarContainer).html();
  var listItemsArray = listItems.match(/(.*<\/li>)/gm);

  // 2- Set up variables
  var listItemsTemp = [];
  var listItemsRearranged = new Array(listItemsArray.length);
  var listItemsRearrangedConcat = new Array(listItemsArray.length);

  // 3- Take listItemsArray and loop through it w/ regex
  for (var i = 0; i < listItemsArray.length; i++) {

    // 4- Use regex to break each list item into five pieces
    listItemsTemp[i] = listItemsArray[i].match(/(<li\b(?:>\s+(?:id="([^"]*)"|class="([^"]*)")|[^\s>]+|\s+)*>)|((<\w+\b>)|(<a\shref=".*">)|(.+?(?=<))|(<\/\w+\b)>)/g);

    // 5- Setup listItemsRearranged[i] with an array of listItemsTemp.length
    listItemsRearranged[i] = new Array(listItemsTemp.length);

    // 6- Take listItemsTemp and reassign positions
    // We can do this because our string will always have five pieces
    listItemsRearranged[i][0] = listItemsTemp[i][1];
    listItemsRearranged[i][1] = listItemsTemp[i][0];
    listItemsRearranged[i][2] = listItemsTemp[i][2];
    listItemsRearranged[i][3] = listItemsTemp[i][4];
    listItemsRearranged[i][4] = listItemsTemp[i][3];

    // 7- Join the array back into a string
    listItemsRearrangedConcat[i] = listItemsRearranged[i].join("");
  }

  // 8- Finally, we rejoin the string and print back into the page
  var listItemsFinal = listItemsRearrangedConcat.join("");
  $(sidebarContainer).html(listItemsFinal);
}
menuItemSwitch(".sidebar-nav");