Answer to Exercise: Fibonacci closure in A Tour of Go

Exercise: Fibonacci closure.go

# An answer to https://tour.golang.org/moretypes/26
# This is a bit more readable than other examples that I found online
# 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 {
	prev, current := -1, 1
	return func() int {
		prev, current = current, prev+current
		return current
	}
}

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