fsm/cmd/iter.go

package main

import (
	"fmt"
	"iter"
)

var max = 5

func s0(yield func() bool) {
	for i := 0; i < max; i++ {
		res := yield()
		fmt.Printf("s0 yield(%d) %t\n", i, res)
	}
}

func s1(yield func(y int) bool) {
	var res = true
	// Stop on our terms, OR if a break was used in the for loop.
	for i := 0; i < max && res; i++ {
		res = yield(i)
		fmt.Printf("s1 yield(%d) %t\n", i, res)
	}
}

func s2(yield func(k int, v int) bool) {
	for x, sq := 0, 0; sq < max; x++ {
		sq = x * x
		res := yield(x, sq)
		fmt.Printf("yield(%d, %d) %t\n", x, sq, res)
	}
}

func main() {
	//for range s0 {
	//	fmt.Print("In range s0: ")
	//}
	//fmt.Println()
	//
	//for k := range s1 {
	//	fmt.Print("In range s1 ")
	//	if k > max/2 {
	//		break
	//	}
	//}
	//fmt.Println()
	//
	//for k := range s2 {
	//	fmt.Print("In range s2 ")
	//	if k > max/2 {
	//		break
	//	}
	//}
	//fmt.Println()
	//
	//for k, v := range s2 {
	//	fmt.Printf("In range s2 %d/%d ", k, v)
	//	if k > max/2 {
	//		break
	//	}
	//}

	next, stop := iter.Pull(s1)
	nw := func() (int, bool) {
		k, ok := next()
		fmt.Printf("next(%d) %t\n", k, ok)
		return k, ok
	}
	for k, ok := nw(); ok; k, ok = next() {
		fmt.Printf("k: %d, ok: %t\n", k, ok)
		if k > max/2 {
			stop()
		}
	}
}