Question

Consider the following code:

(function($) {
  function hello(who)
  {
    console.log('Hello: '+who);
  }
})(jQuery);

$(document).ready(function() {
  hello('World');
});

How would it be possible to access the hello function from outside the anonymous function?

Answer 1

Assuming you’re going to want to eventually add other methods to this closure as well, you could create a namespace using the module pattern:

var myAppNamespace = (function($){
  var exports = {}, // the return object
      helloText = 'Hello: '; // private variable

  function concatText() {
    var returnString = '';
    for (var i = 0, il = arguments.length; i < il; i++) {
      returnString += arguments[i];
    }
    return returnString;
  } // private method

  exports.world = 'World'; // public property
  exports.hello = function ( who ) {
    console.log(concatText(helloText, who));
  }; // public method

  return exports; // assign exports to myAppNamespace
}(jQuery));

Here the methods and properties are just to show examples of ways to declare things privately and publicly within the closure. For illustration:

myAppNamespace.hello(myAppNamespace.world); // -> Hello: World
myAppNamespace.hello('Bob'); // -> Hello: Bob
myAppNamespace.helloText; // undefined
myAppNamespace.concatText; // undefined

Also, I used the $ argument in the self-executing function so that jQuery is passed to something, you’d use $ internally to access jQuery.