Summarize of Kotlin Enum

6. Enum

1. Initialization

Enum classes as any other classes can have a constructor and be initialized

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enum class Color (val rgb: Int){
    RED(0xFF000),
    GREEN(0x00FF00),
    BLUE(0x0000FF)
}

2. Simple Enum

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enum class Color2{
    RED, GREEN, BLUE
}

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

3. Mutability

Enums can be mutable, this is another way to obtain a singleton behavior:

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enum class Color3(var x : Int = 0){
    EARTH(7 * 10000),
    MARS();

    override fun toString(): String = "$name [x = $x]"
}
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var c = Color3.MARS
println(c)
c.x = 1234
println(c)