Backbone.js报错：'instanceof'右侧不是对象，求解决方案

Hey there! Let's tackle this tricky intermittent error you're hitting with Backbone and require.js. That TypeError: Right-hand side of 'instanceof' is not an object message points straight to one key issue: Backbone.$ isn't properly set to a jQuery object when your View tries to initialize. Since it only happens sometimes and fixes with a refresh, this is almost certainly a module loading timing problem.

Here are concrete steps to diagnose and fix this:

1. Lock in Backbone's Dependencies with require.js Shim #

Backbone relies on jQuery (and Underscore) to set Backbone.$ automatically. If your require.js config isn't enforcing the load order, Backbone might initialize before jQuery is ready. Update your require config to explicitly declare dependencies:

require.config({
  paths: {
    'jquery': 'path/to/jquery',
    'underscore': 'path/to/underscore',
    'backbone': 'path/to/backbone'
  },
  shim: {
    'backbone': {
      // Ensure jQuery and Underscore load before Backbone
      deps: ['jquery', 'underscore'],
      exports: 'Backbone'
    }
  }
});

2. Manually Set Backbone.$ to Guarantee jQuery Reference #

Sometimes automatic binding fails due to async load quirks. Explicitly assign Backbone.$ in your module before initializing any Views:

define(['jquery', 'backbone'], function($, Backbone) {
  // Force Backbone to use the loaded jQuery instance
  Backbone.$ = $;
  
  // Now initialize your app/views safely
  var app = new YourApplicationView();
});

3. Check for Duplicate Library Loads #

Accidentally loading jQuery or Backbone twice (e.g., one via require.js and another via a <script> tag) can create conflicting instances. This might cause Backbone.$ to point to an uninitialized or mismatched jQuery object. Audit your HTML and require config to ensure only one instance of each library is loaded.

4. Validate Module Dependencies Across Your Codebase #

Look at the error stack trace referencing require.js:1690—this means a module is executing before its dependencies are ready. Double-check every module that uses Backbone Views:

• Make sure 'backbone' is listed in the define dependency array
• Confirm the Backbone parameter is properly received in the module's callback function

5. Consider Upgrading Backbone (Optional but Recommended) #

Backbone 1.1.0 is quite outdated. Later versions (1.2.0+) include fixes for dependency handling and initialization edge cases that could resolve this intermittent issue. If your project allows, test an upgrade to a stable newer version (just be sure to check for breaking changes with your existing code).

The core fix here is ensuring Backbone has a fully initialized jQuery reference before any View code runs. These steps should eliminate the race condition causing your intermittent error.

内容的提问来源于stack exchange，提问作者barthuin