30 lines
435 B
Go
30 lines
435 B
Go
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package main
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import (
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"fmt"
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"sync"
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)
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// START OMIT
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func main() {
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var once sync.Once
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onceBody := func() {
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fmt.Println("Only once")
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}
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done := make(chan bool)
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for i := 0; i < 10; i++ {
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go func() {
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// prints "Only once" once, though Do() is called ten times.
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once.Do(onceBody)
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done <- true
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}()
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}
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for i := 0; i < 10; i++ {
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<-done // wait for all goroutines to finish.
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}
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fmt.Println("complete")
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}
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// END OMIT
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