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// $G $D/$F.go && $L $F.$A && ./$A.out
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package main
var counter uint
var shift uint
func GetValue() uint {
counter++
return 1 << shift
}
func Send(a, b chan uint) int {
var i int
LOOP:
for {
select {
case a <- GetValue():
i++
a = nil
case b <- GetValue():
i++
b = nil
default:
break LOOP
}
shift++
}
return i
}
func main() {
a := make(chan uint, 1)
b := make(chan uint, 1)
if v := Send(a, b); v != 2 {
println("Send returned", v, "!= 2")
panic("fail")
}
if av, bv := <-a, <-b; av|bv != 3 {
println("bad values", av, bv)
panic("fail")
}
if v := Send(a, nil); v != 1 {
println("Send returned", v, "!= 1")
panic("fail")
}
if counter != 10 {
println("counter is", counter, "!= 10")
panic("fail")
}
}
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