範囲型っぽいなにか

scope.go

package main

import "fmt"

type scope struct {
	min, max int
}

func NewScope(min, max int) *scope {
	return &scope{min, max}
}

func (s scope) Each() chan int {
	c := make(chan int)
	go func() {
		for i := s.min; i <= s.max; i++ {
			c <- i
		}
		close(c)
	}()
	return c
}

func main() {
	for i := range NewScope(1, 10).Each() {
		fmt.Println(i)
	}
}