Extensions deprecated

Extensions add or replace functionality during runtime and are referenced by a unique id

based on this oxpedia article

Attributes

property	description
id	unique
index	(optional): numeric value used for specify order of execution (also valid are 'first' and 'last')
(functionname)	as required by the extension point contract

example

//defining a extension for some extension point that requires a draw function
{
    id: 'example1',
    index: 100,
    draw: function () {
        //draw something
    }
};

Execution order

To ensure your extension is called first or last use the index 'first' or 'last'. Keep in mind that a defined call order does not guarantees all extensions with a lower index finished already when your extension is called (for example some asynchronous code). Nevertheless for the most common use case (draw extensions that create/modify nodes with already present data) this execution order should be quite reliable to do some DOM manipulation within an custom extension indexed as 'last'. If more than one extension of a point has the index 'first' or 'last' these will be executed first/last in the order they were added.