41 lines
616 B
Go
41 lines
616 B
Go
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package main
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import (
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"fmt"
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"time"
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)
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func main() {
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a, b := make(chan bool), make(chan bool)
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go func() {
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for a != nil || b != nil {
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fmt.Println("loop starts")
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select {
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case <-a:
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fmt.Println("recv: a")
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a = nil
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case <-b:
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b = nil
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fmt.Println("recv: b")
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}
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fmt.Println("loop ends")
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}
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fmt.Println("gopher dies")
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}()
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time.Sleep(time.Second)
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// a <- true
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close(a)
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time.Sleep(time.Second)
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//b <- true
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close(b)
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time.Sleep(time.Second * 2)
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// closed chan never blocks
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// nil chan always blocks
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// if in the loop chans not set to nil, the loop will loop forever
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}
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