type checking for allowable football substitutions

maradona.ts

type Player<Club extends string> = {
  club: Club,
  name: string
};

function createPlayer<Club extends string>(club: Club, name: string): Player<Club> {
  return { club, name };
}

const maradona = createPlayer('Dynamo Brest', 'Maradona');
const milevskij = createPlayer('Dynamo Brest', 'Milevskij');
const ronaldo = createPlayer('Dynamo Minsk', 'Ronaldo');

type Substitution<PlayerIn, PlayerOut> = {
  playerIn: PlayerIn,
  playerOut: PlayerOut
};

function substitute<ClubOut extends string>(playerOut: Player<ClubOut>) {
  return (
    <ClubIn extends ClubOut>(playerIn: Player<ClubIn>): Substitution<Player<ClubIn>, Player<ClubOut>> => 
      (
        {
          playerIn, 
          playerOut
        }
      )
  ); 
}

const s1 = substitute(milevskij)(maradona);  // OK
const s2 = substitute(maradona)(ronaldo);    // ERROR -- they are from different clubs!