Enum Classes

Enum Classes

The most basic usage of enum classes is implementing type-safe enums

enum class Direction {
    NORTH, SOUTH, WEST, EAST
}

Each enum constant is an object. Enum constants are separated with commas.

Initialization

Since each enum is an instance of the enum class, they can be initialized

enum class Color(val rgb: Int) {
        RED(0xFF0000),
        GREEN(0x00FF00),
        BLUE(0x0000FF)
}

Anonymous Classes

Enum constants can also declare their own anonymous classes

enum class ProtocolState {
    WAITING {
        override fun signal() = TALKING
    },

    TALKING {
        override fun signal() = WAITING
    };

    abstract fun signal(): ProtocolState
}

with their corresponding methods, as well as overriding base methods. Note that if the enum class