Function closest

Sortable.js:164–176

( /**HTMLElement*/el, /**String*/selector, /**HTMLElement*/ctx, includeCTX)

    return el.host && el !== document && el.host.nodeType && el.host !== el ? el.host : el.parentNode;
  }
  function closest( /**HTMLElement*/el, /**String*/selector, /**HTMLElement*/ctx, includeCTX) {
    if (el) {
      ctx = ctx || document;
      do {
        if (selector != null && (selector[0] === '>' ? el.parentNode === ctx && matches(el, selector) : matches(el, selector)) || includeCTX && el === ctx) {
          return el;
        }
        if (el === ctx) break;
        /* jshint boss:true */
      } while (el = getParentOrHost(el));
    }
    return null;
  }
  var R_SPACE = /\s+/g;
  function toggleClass(el, name, state) {
    if (el && name) {