A Tour of Go - Exercise: Fibonacci closure

exercise-fibonacci-closure.go

// Let's have some fun with functions.
// 
// Implement a fibonacci function that returns a function (a closure) that returns 
// successive fibonacci numbers (0, 1, 1, 2, 3, 5, ...).
package main

import "fmt"

// fibonacci is a function that returns
// a function that returns an int.
func fibonacci() func() int {
	previous := 0
	last := 1
	result := 0
	return func() int {
		result, previous, last = previous, last, (previous + last)
		return result
	}
}

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