osp-good.ts

class PokemonType {
  name string
  strongAgainstList Array<string>
  
  getName(): string {
    return this.name
  }
  getStrongAgainstList(): Array<string> {
    return this.strongAgainstList
  }
  isStrongAgainst(pokemonType): boolean {
    return this.getStrongAgainstList().includes(pokemonType.getName())
  }
}

class Pokemon {
  pokemonType PokemonType
  
  getType(): PokemonType {
    return this.pokemonType
  }
  beats(enemyPokemon: Pokemon) {
    return this.getType().isStrongAgainst(enemyPokemon.getType())
  }
}

class NormalPokemonType extends PokemonType {
  name = "normal"
  strongAgainstList = []
}

class FightingPokemonType extends PokemonType{
  name = "fighting"
  strongAgainstList = ["normal"]
}

class NormalPokemon extends Pokemon {
  pokemonType = new NormalPokemonType
}

class FightingPokemon extends Pokemon {
  pokemonType = new FightingPokemonType
}

const snorlax = new NormalPokemon
const machomp = new FightingPokemon

machomp.beats(snorlax)  // true