Example of type erasure with Pokemon

TypeErasure.swift

class Thunder { }
class Fire { }

protocol Pokemon {
    typealias PokemonType
    func attack(move: PokemonType)
}

struct Pikachu: Pokemon {
    typealias PokemonType = Thunder
    func attack(move: Thunder) { print("️--------Thunder Attack") }
}

class Charmander: Pokemon {
    typealias PokemonType = Fire
    func attack(move: Fire) { print("-------Fire Attack") }
}

class Raichu: Pokemon {
    typealias PokemonType = Thunder
    func attack(move: Thunder) { print("-------Thunder Attack") }
}

class AnyPokemon<PokemonType>: Pokemon {
    private let _attack: ((PokemonType) -> Void)

    required init<U: Pokemon where U.PokemonType == PokemonType>(_ pokemon: U) {
        _attack = pokemon.attack
    }

    func attack(type: PokemonType) {
        return _attack(type)
    }
}

let thunderAttack = Thunder()
let fireAttack = Fire()

let pikachu: AnyPokemon<Thunder> = AnyPokemon(Pikachu())
let raichu: AnyPokemon<Thunder> = AnyPokemon(Raichu())
let electricPokemon = [pikachu, raichu]
let charmander: AnyPokemon<Fire> = AnyPokemon(Charmander())

for pokemon in electricPokemon {
    pokemon.attack(thunderAttack)
}
charmander.attack(fireAttack)

Awesome! Did you ever build something with type erasure?