package ui type Key int const ( KeyUp Key = iota KeyDown KeyLeft KeyRight KeySpace KeyMax ) var currentKeyboard Keyboard type Keyboard interface { IsKeyPressed(key Key) bool } func SetKeyboard(keyboard Keyboard) { currentKeyboard = keyboard } func IsKeyPressed(key Key) bool { if currentKeyboard == nil { panic("ui.IsKeyPressed: currentKeyboard is not set") } return currentKeyboard.IsKeyPressed(key) }