3 var isObject = require('is-extendable');
5 module.exports = function extend(o/*, objects*/) {
6 if (!isObject(o)) { o = {}; }
8 var len = arguments.length;
9 for (var i = 1; i < len; i++) {
10 var obj = arguments[i];
19 function assign(a, b) {
28 * Returns true if the given `key` is an own property of `obj`.
31 function hasOwn(obj, key) {
32 return Object.prototype.hasOwnProperty.call(obj, key);