The Flyweight Pattern in Go, Example Two

example2.go

// Player represents a player in a game.
type Player struct {
    ID uint32
    Handle, Name, Country string
    Games []string
}

// cachedPlayer is a Player, but without the Games field.
type cachedPlayer struct {
    ID uint32
    Handle, Name, Country string
}

var games = []string{"Flappy Fish", "Ducks'n'Dogs", "Backflip Pro"}

var crashyGamesPlayers map[uint32]cachedPlayer

// convertWith returns the Player that matches cachedPlayer,
// with game titles attached.
func (c cachedPlayer) convertWith(games []string) Player {
    return Player{
        ID: c.ID,
        Handle: c.Handle,
        Name: c.Name,
        Country: c.Country,
        Games: games,
   }
}

// FindPlayerByID returns the player with the given ID, if exists.
// Otherwise, an empty Player is returned.
func FindPlayerByID(ID uint32) Player {
    if cp, ok := crashyGamesPlayers[ID]; ok {
        // cachedPlayer found.
        return cp.convertWith(games) // Using globally cached games.
    }
    return Player{}
}