Extending Array in TypeScript

Question

How to add a method to a base type, say Array? In the global module this will be recognized

interface Array {    remove(o): Array; } 

but where to put the actual implementation?

Answer 1

You can use the prototype to extend Array:

interface Array<T> {     remove(o: T): Array<T>; }  Array.prototype.remove = function (o) {     // code to remove "o"     return this; } 

If you are within a module, you will need to make it clear that you are referring to the global Array<T>, not creating a local Array<T> interface within your module:

declare global {     interface Array<T> {         remove(o: T): Array<T>;     } }