Typescript: generic that extends a type with a generic (higher kinded types)

Question

Say I have an interface

interface Applicative<T> {}

Now I want to define a function f that:

• takes a function and takes a type U extending an Applicative wrapping Any
• and returns an U wrapping a function

How do I define this in Typescript ?

 function f<U extends Applicative>(fn: Function, a: U<any>): U<Function>

is my naive attempt but this is not valid

Answer 1

Unfortunately, typescript does not (yet?) implement higher kinded types.

See https://github.com/Microsoft/TypeScript/issues/1213 for details