Go: 使用 Channel 处理多值返回

chan.go

package main

import (
	"log"
	"time"
)

func main() {
	log.Println("start")
	num, err := func() (int, error) {
		n := make(chan int, 1)
		e := make(chan error, 1)
		go func() {
			defer close(n)
			defer close(e)

			// Stand-in for a IO operation
			time.Sleep(time.Second * 3)
			n <- 100
			e <- nil
		}()
		return <-n, <-e
	}()
	log.Println(num, err)
}