Messing around with functional progamming in TypeScript

compose.ts

export default function compose<T>(...functions: { (x: T): T }[]) {
	return x => functions.reduce((previous, current) => x => current(previous(x)))(x);
}

/* usage:
const composed = compose<number>(x => x * 2,x => x * 3, x => x * 4);

console.log(composed(4)) //96

or

const composed = compose<string>(x=>x.toUpperCase(),x=>x+' :)')

console.log(`Hello ${composed('John Doe')}`); // Hello JOHN DOE :)
*/

An implementation of the compose function in TypeScript.