Golang Merge多个channel的response到一

package orch

type Orch struct {
}

func New() *Orch {
    return &Orch{}
}

func (orch *Orch) Or(channels ...<-chan interface{}) <-chan interface{} {
    switch len(channels) {
    case 0:
        return nil
    case 1:
        return channels[0]
    }

    orDone := make(chan interface{})
    go func() {
        defer close(orDone)
        switch len(channels) {
        case 2:
            select {
            case <-channels[0]:
            case <-channels[1]:
            }
        default:
            select {
            case <-channels[0]:
            case <-channels[1]:
            case <-channels[2]:
            case <-orch.Or(append(channels[3:], orDone)...):
            }
        }
    }()
    return orDone
}

package main

import (
    "fmt"
    "mergechanresponse/orch"
    "time"
)

func main() {
    sig := func(after time.Duration) <-chan interface{} {
        c := make(chan interface{})
        go func() {
            defer close(c)
            time.Sleep(after)
        }()
        return c
    }

    och := orch.New()

    start := time.Now()
    <-och.Or(
        sig(2*time.Hour),
        sig(5*time.Minute),
        sig(1*time.Second),
        sig(1*time.Hour),
        sig(1*time.Minute),
    )

    fmt.Printf("done after %v \n", time.Since(start))

}

程序输出如下，实现一个channel退出，所有channel都退出的功能。