Callback before RequireJS “define” function is called?

问题

I'm new to Backbone, and i'm helping to maintain an app that has lots of Backbone and RequireJS code that does something like so:

define(

    ['backbone', 'underscore'],

    function(Backbone, _) {
      // some code here
    }
);

I'd like to configure Underscore in each of these pages... In the most simple sense, I could just do something like so:

define(

    ['backbone', 'underscore'],

    function(Backbone, _) {

      // do some stuff to configure underscore
      configureUnderscore(_);

    }
);

but I'd like to leave each page's define function alone, and just inject a callback that's called before the define callback is called.

How can this be done with Backbone or RequireJS?

回答1:

The simplest would probably to define a requireJS module named (e.g.) rawUnderscore which returns Undercore without any configuration.

Then, create a new module named underscorewhich requires rawUnderscore and configures it before returning its value.

回答2:

Here's how to make this work as suggested in another answer on this page, and copied from this StackOverflow answer to a similar question:

main.js

requirejs.config({
    paths: {
        'underscore': 'underscoreConfig',
        'originalUnderscore': 'underscore'
    },
    shim: {
        'originalUnderscore': {
            exports: '_'
        }
    }
});

underscoreConfig.js

define(['originalUnderscore'], function(_) {
    _.templateSettings =
    {
        evaluate    : /<%([\s\S]+?)%>/g,
        interpolate : /<%cleanHtml([\s\S]+?)%>/g,
        escape      : /<%[=-]([\s\S]+?)%>/g
    };
    return _;
});

回答3:

Another approach (completely untested) may be to define a "require" variable before require.js is included, as detailed here in the Require.JS docs, and here as well

<script>
    var require = {
        deps: ["some/module1", "my/module2", "a.js", "b.js"],
        callback: function(module1, module2) {
            //This function will be called when all the dependencies
            //listed above in deps are loaded. Note that this
            //function could be called before the page is loaded.
            //This callback is optional.
        }
    };
</script>
<script src="scripts/require.js"></script>

来源：https://stackoverflow.com/questions/22201119/callback-before-requirejs-define-function-is-called

标签

javascript

backbone.js

requirejs