docs: function expand (node, args, i) {
  	var n = args.length;
  	var arg;
  	for (; i < n; i++) {
  		arg = args [i];
  		if (isNodeType (arg, types.MACRO)) {
  			expand (node, arg, 1);
  
  		} else {
  			node.push (arg);
  		}
  	}
  	return node;
  }