64 lines
1.4 KiB
V
64 lines
1.4 KiB
V
import context
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import time
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const (
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// a reasonable duration to block in an example
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short_duration = 1 * time.millisecond
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)
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fn after(dur time.Duration) chan int {
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dst := chan int{}
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go fn (dur time.Duration, dst chan int) {
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time.sleep(dur)
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dst <- 0
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}(dur, dst)
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return dst
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}
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// This example passes a context with an arbitrary deadline to tell a blocking
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// function that it should abandon its work as soon as it gets to it.
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fn test_with_deadline() {
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dur := time.now().add(short_duration)
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ctx := context.with_deadline(context.background(), dur)
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defer {
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// Even though ctx will be expired, it is good practice to call its
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// cancellation function in any case. Failure to do so may keep the
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// context and its parent alive longer than necessary.
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context.cancel(ctx)
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}
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after_ch := after(1 * time.second)
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ctx_ch := ctx.done()
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select {
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_ := <-after_ch {
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assert false
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}
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_ := <-ctx_ch {
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assert true
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}
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}
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}
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// This example passes a context with a timeout to tell a blocking function that
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// it should abandon its work after the timeout elapses.
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fn test_with_timeout() {
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// Pass a context with a timeout to tell a blocking function that it
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// should abandon its work after the timeout elapses.
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ctx := context.with_timeout(context.background(), short_duration)
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defer {
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context.cancel(ctx)
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}
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after_ch := after(1 * time.second)
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ctx_ch := ctx.done()
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select {
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_ := <-after_ch {
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assert false
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}
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_ := <-ctx_ch {
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assert true
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}
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}
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}
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