Representation of Enums in Go

In Go, there is no built-in enum type like in some other programming languages. However, there are idiomatic ways to represent enums using constants and custom types.

Using Constants

One way to represent enums in Go is by using a set of constants. By assigning unique values to each constant, you can create a set of distinct enum values.

Example

package main

import "fmt"

const (
    Red   = iota // 0
    Green = iota // 1
    Blue  = iota // 2
)

func main() {
    color := Green

    switch color {
    case Red:
        fmt.Println("Color is Red")
    case Green:
        fmt.Println("Color is Green")
    case Blue:
        fmt.Println("Color is Blue")
    default:
        fmt.Println("Unknown Color")
    }
}

Using iota with Custom Types

Another idiomatic approach to represent enums in Go is by using iota with custom types. This allows you to create a more expressive and type-safe enum representation.

Example

package main

import "fmt"

type Color int

const (
    Red Color = iota // 0
    Green            // 1
    Blue             // 2
)

func main() {
    color := Green

    switch color {
    case Red:
        fmt.Println("Color is Red")
    case Green:
        fmt.Println("Color is Green")
    case Blue:
        fmt.Println("Color is Blue")
    default:
        fmt.Println("Unknown Color")
    }
}