Is it possible to wrap a function and retain its types?

Question

I'm trying to create a generic wrapper function which will wrap any function passed to it.

At the very basic the wrapper function would look something like

function wrap<T extends Function>(fn: T) {     return (...args) => {         return fn(...args)     }; } 

I'm trying to use it like:

function foo(a: string, b: number): [string, number] {     return [a, b]; }  const wrappedFoo = wrap(foo); 

Right now wrappedFoo is getting a type of (...args: any[]) => any

Is it possible to get wrappedFoo to mimic the types of the function its wrapping?

Answer 1

This works with any number of arguments, and keep all the arguments & return types

const wrap = <T extends Array<any>, U>(fn: (...args: T) => U) => {   return (...args: T): U => fn(...args) }