First class functions in Go

Question

I come from JavaScript which has first class function support. For example you can:

• pass a function as a parameter to another function
• return a function f

Answer 1

While you can use a var or declare a type, you don't need to. You can do this quite simply:

package main

import "fmt"

var count int

func increment(i int) int {
    return i + 1
}

func decrement(i int) int {
    return i - 1
}

func execute(f func(int) int) int {
    return f(count)
}

func main() {
    count = 2
    count = execute(increment)
    fmt.Println(count)
    count = execute(decrement)
    fmt.Println(count)
}

//The output is:
3
2