File size: 1,389 Bytes
13c2bf6 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 | // Copyright 2023 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.
// Tests coroutine switches.
//go:build ignore
package main
import (
"iter"
"log"
"os"
"runtime/trace"
"sync"
)
func main() {
// Start tracing.
if err := trace.Start(os.Stdout); err != nil {
log.Fatalf("failed to start tracing: %v", err)
}
// Try simple pull iteration.
i := pullRange(100)
for {
_, ok := i.next()
if !ok {
break
}
}
// Try bouncing the pull iterator between two goroutines.
var wg sync.WaitGroup
var iterChans [2]chan intIter
wg.Add(2)
iterChans[0] = make(chan intIter)
iterChans[1] = make(chan intIter)
go func() {
defer wg.Done()
iter := pullRange(100)
iterChans[1] <- iter
for i := range iterChans[0] {
_, ok := i.next()
if !ok {
close(iterChans[1])
break
}
iterChans[1] <- i
}
}()
go func() {
defer wg.Done()
for i := range iterChans[1] {
_, ok := i.next()
if !ok {
close(iterChans[0])
break
}
iterChans[0] <- i
}
}()
wg.Wait()
// End of traced execution.
trace.Stop()
}
func pullRange(n int) intIter {
next, stop := iter.Pull(func(yield func(v int) bool) {
for i := range n {
yield(i)
}
})
return intIter{next: next, stop: stop}
}
type intIter struct {
next func() (int, bool)
stop func()
}
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