1 package main 2 3 import "fmt" 4 5 // fib returns a function that returns 6 // successive Fibonacci numbers. 7 func fib() func() int { 8 a, b := 0, 1 9 return func() int { 10 a, b = b, a+b 11 return a 12 } 13 } 14 15 func main() { 16 f := fib() 17 // Function calls are evaluated left-to-right. 18 fmt.Println(f(), f(), f(), f(), f()) 19 } 20
