backbone.js lack of slash before # breaking relative path
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I'm using backbone.js on client side and express.js on server-side.
The problem is that, with backbone.js routing, the user can either have or have-not a slash before the #, which is breaking relative path in AJAX.

happy path url:

    localhost:3000/ab/#/cd
    // now if
    // $.ajax({ "url" : "pay", ... });
    // the request url would be
    localhost:3000/ab/pay

All looks great in the happy path, but...

sad path url:

    localhost:3000/ab#/cd
    // with same AJAX, the request url becomes
    localhost:3000/pay

How should I solve this problem?