Design Patterns used in the jQuery library

Question

jQuery is highly focused on the DOM and provides a nice abstraction around it. In doing so, it makes use of various well known design patterns which just hit me yesterday. O

Answer 1

The Composite pattern is also very commonly used in jQuery. Having worked with other libraries, I can see how this pattern is not so obvious as it looks at first sight. The pattern basically says that,

a group of objects are to be treated in the same way as a single instance of an object.

For example, when dealing with a single DOM element or a group of DOM elements, both can be treated in a uniform manner.

$('#someDiv').addClass('green'); // a single DOM element

$('div').addClass('green');      // a collection of DOM elements