fibonacci sequence golang implementation

fib.go

package main

import (  
    "fmt"
)

func fib() func() int{
	a, b := 0, 1
	return func() int{
		a, b = b, a+b
		return b-a
	}
}

func main() {
	t := fib()
	for i:=0; i < 20; i++{
		fmt.Println(t())
	}
}