code: function appendMeArgs (e, args /* null/undefined, string, node, or array-like of nodes incl.
  			live NodeList */, attrsP) {
    if (args == null) ;
    else if (typeof args == 'string')
      e.appendChild(e.ownerDocument.createTextNode(args));
    else if (args.nodeType) e.appendChild(args);
    else {
      if (args.constructor != Array) args = F.slice(args);	// for live NodeList
      F.iter(function (x) {
        e.appendChild(x);
      }, args);
    }
    return M.setAttrs(e, attrsP);
  }
docs: MathML namespace