https://tour.golang.org/moretypes/26

fibonacci.go

package main

import "fmt"

// fibonacci 函数会返回一个返回 int 的函数。
func fibonacci() func() int {
	n0 := 0
	n1 := 1
	return func() int {
		n2 := n0 + n1
		n0 = n1
		n1 = n2
		return n2
	}
}

func main() {func main() {
	f := fibonacci()
	for i := 0; i < 10; i++ {
		fmt.Println(f())
	}
}

fibonacci.js

function fibonacci() {
	var n0 = 0
	var n1 = 1
	return function() {
		n2 = n0 + n1
		n0 = n1
		n1 = n2
		return n2
	}
}

var f = fibonacci()
for (var i = 0; i < 10; i++) {
  console.log(f())
}