Function registerCallbacks

06.Router/basic/js/vue.js:8124–8137

* Register callbacks for option events and watchers. * * @param {Vue} vm * @param {String} action * @param {Object} hash

(vm, action, hash)

     */

    function registerCallbacks(vm, action, hash) {
      if (!hash) return;
      var handlers, key, i, j;
      for (key in hash) {
        handlers = hash[key];
        if (isArray(handlers)) {
          for (i = 0, j = handlers.length; i < j; i++) {
            register(vm, action, key, handlers[i]);
          }
        } else {
          register(vm, action, key, handlers);
        }
      }
    }

    /**
     * Helper to register an event/watch callback.