Question

I’m writing a Mootools plugin and having trouble understanding a scoping issue. Some code to convey my context:

var pluginName = new Class({
   implements: [ Options ],

  initialize: function(paramOne, options) {
    this.setOptions(options);
  },

  someFunction: function() {
    $$('menu').each(function(menu) {
      // SCOPE OF INTEREST
    });
  }
};

I’m wondering if there is a way to access the options object in the scope where I’ve written ‘SCOPE OF INTEREST’. I know one way would be to set a variable at the beginning of someFunction like so:

someFunction: function() {
    var optionIWantToAccess = this.options.relevantOption;
    $$('menu').each(function(menu) {
      // now optionIWantToAccess is available here
    });
  }

but this seems kind of clumsy and smells of a better alternative. A more general version of this question is: Can I access the class-level scope (not sure if that’s the right term….but the scope inside the initialize function is what I’m talking about) inside a Mootools iterator?

Any help on this would be greatly appreciated.

Thanks.

Answer 1

You can bind the function to the instance.

someFunction: function() {
  $$('menu').each(function(menu) {
    // 'this' is still the original instance
    this.options.relevantOption;
  }.bind(this))
}

Function#bind is not available in old browsers, but adding support for it is very straight-forward.