34 lines
454 B
V
34 lines
454 B
V
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import sync
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struct One {
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pub mut:
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i int
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}
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fn (mut o One) add(i int) {
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o.i = o.i + i
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}
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fn run(mut once sync.Once, mut o One, c chan bool) {
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once.do(fn [mut o] () {
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o.add(5)
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})
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c <- true
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}
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fn test_once() {
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mut o := &One{}
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mut once := sync.new_once()
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c := chan bool{}
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n := 10
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// It is executed 10 times, but only once actually.
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for i := 0; i < n; i++ {
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go run(mut once, mut o, c)
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}
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for i := 0; i < n; i++ {
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<-c
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}
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assert o.i == 5
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}
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