jquery callback

calling_out.js

MyObject = {
  respondToCallback: function (response, context) {
    // context will === "abc123" when called via doingSomething()
  },
  doingSomething: function(callback) {
    var _foo = "abc123";
    var _self = this;
    var _default_callback = function (resp, status, jqxhr) { 
      _self.respondToCallback(response, _foo);
    };
    var _callback = callback || _default_callback;
    $.getJSON(_url, _params, _callback);
  }
};

calling_out2.js

function MyObject (initializer_params) {
  var self = this;
  
  self.respondToCallback = function (resp, ctx) { ... };
  
  self.doingSomething = function (callback) {
    ...
    var _default_callback = function (r, s, x) {
      self.respondToCallback(r, _foo);
    };
    ...
  };
  
  return self;
}