Uhmm Go have first class functions

firstclassfunctions.go

// Playing with functions
// This is really useful
package main

import "fmt"

func greet() {
	fmt.Println("Hello!")
}
func farewell() {
	fmt.Println("GoodBye!")
}

type fn func()

func machine(f fn) {
	f()
}

func main() {
	machine(greet)
	machine(farewell)
}

Looking how to pass functions as parameters..