// Compile Error: Val cannot reassigned var valueB = "Hello" valueB = "Konnichiwa!" // OK // null許容 var valueNullable: String? = "Hogehoge" valueNullable = null // null非許容 var valueNonNullable = "Mogemoge" valueNonNullable = null // Error: Null can not be a value of a non-null type String