• 枚举

    枚举

    1. enum Color {
    2.     red green blue 
    3. } 
    5. mut color := Color.red
    6. // V knows that `color` is a `Color`. No need to use `Color.green` here.
    7. color = .green 
    8. println(color) // ==> "1"  TODO: print "green"?