/** If you want to know how to encoding HKTs in typescript, check this: 
    https://gist.github.com/ENvironmentSet/1662a140f99381bc85fd6be51ecdcbb5
    
    Sorry for messy names, this was only PoC.                            **/

export interface HKT {
  param: unknown;
  result: unknown;
}

export type Apply<f extends HKT, x>
  = (f & { param: x })['result'];

export type ElimWithConstraint<constraint extends HKT> = <R>(f: <A>(x: Apply<constraint, A>) => R) => R;
export function makeElimWithConstraint<constraint extends HKT>(): <A>(x: Apply<constraint, A>) => ElimWithConstraint<constraint> {
  return x => f => f(x);
}