Tour of Go 2.0

Switch

A switch statement is a cleaner alternative to a long chain of if-else blocks. It runs the first case that matches — and only that case.

Here’s the big difference from C, Java, or JavaScript: Go does not fall through by default. No need to write break at the end of every case — Go adds it automatically.

Two more things worth knowing: switch cases don’t have to be constants, and the values don’t have to be integers. Go is more flexible here than most languages.

main.go ▶ Run in Playground 
package main

import (
	"fmt"
	"runtime"
)

func main() {
	fmt.Print("Go runs on ")
	switch os := runtime.GOOS; os {
	case "darwin":
		fmt.Println("macOS.")
	case "linux":
		fmt.Println("Linux.")
	default:
		// freebsd, openbsd,
		// plan9, windows...
		fmt.Printf("%s.\n", os)
	}
}