http://www.paulgraham.com/accgen.html

paul_graham.go

package main

import "fmt"

func foo(n int) (f1 func(int) int, f2 func(int) int) {
	f1 = func(i int) int {
		n += i
		return n
	}
	f2 = func(i int) int {
		n -= i
		return n
	}
	return
}

func main() {
	f, g := foo(5)
	fmt.Println(f(1))
	fmt.Println(f(1))
	fmt.Println(f(1))
	fmt.Println(f(1))

	fmt.Println(g(1))
	fmt.Println(g(1))
	fmt.Println(g(1))
	fmt.Println(g(1))
}