Learning JavaScript Design Patterns

Prototypal Inheritance with the DOM-to-Object Bridge Pattern

As covered earlier, in JavaScript, we don’t have the traditional notion of classes that we would find in other classical programming languages, but we do have prototypal inheritance. With prototypal inheritance, an object inherits from another object. We can apply this concept to jQuery plug-in development.

Yepnope.js author Alex Sexton and jQuery team member Scott Gonzalez have looked at this topic in detail. In sum, they discovered that for organized modular development, clearly separating the object that defines the logic for a plug-in from the plug-in generation process itself can be beneficial.

The benefit is that testing our plug-in’s code becomes significantly easier, and we are also able to adjust the way things work behind the scenes without altering the way that any object APIs we implement are used.

In Sexton’s article on this topic, he implemented a bridge that enables us to attach our general logic to a particular plug-in, which we’ve implemented in the pattern below.

One of the other advantages of this pattern is that we don’t have to constantly repeat the same plug-in initialization code, thus ensuring that the concepts behind DRY development are maintained. Some developers might also find this pattern easier to read than others.

/*!
 * jQuery prototypal inheritance plugin boilerplate
 * Author: Alex Sexton, Scott Gonzalez
 * Further changes: @addyosmani
 * Licensed under the MIT license
 */


// myObject - an ...