On Saturday, August 31, 2019 at 2:32:26 AM UTC-4, rog wrote: > > The reason you're wanting priority select is because you are shutting down > the data channel preemptively, but you can wait for an acknowledgement from > the run goroutine instead: > > https://play.golang.org/p/qSWluYy4ifl > > Your solution is clever. The Close method can be called multiple time safely. Is there such a beautiful solution for multiple senders?
> > On Wed, 28 Aug 2019 at 18:06, T L <tapi...@gmail.com <javascript:>> wrote: > >> The old thread: >> https://groups.google.com/forum/#!topic/golang-nuts/ZrVIhHCrR9o >> >> Go channels are flexible, but in practice, I often encountered some >> situations in which channel are hard to use. >> Given an example: >> >> import "math/rand" >> >> type Producer struct { >> data chan int >> closed chan struct{} >> } >> >> func NewProducer() *Producer { >> p := &Producer { >> data: make(chan int), >> closed: make(chan struct{}), >> } >> >> go p.run() >> >> return p >> } >> >> func (p *Produce) Stream() chan int { >> return p.data >> } >> >> func (p *Producer) run() { >> for { >> // If non-blocking cases are selected by their appearance order, >> // then the following slect block is a perfect use. >> select { >> case(0) <-p.closed: return >> case p.data <- rand.Int(): >> } >> } >> } >> >> func (p *Produce) Clsoe() { >> close(p.closed) >> close(p.data) >> } >> >> func main() { >> p := NewProducer() >> for n := p.Stream() { >> // use n ... >> } >> } >> >> >> If the first case in the select block in the above example has a higher >> priority than the second one, >> then coding will be much happier for the use cases like the above one. >> >> In short, the above use case requires: >> * for receivers, data streaming end is notified by the close of a channel. >> * for senders, data will never be sent to closed channel. >> >> But, as Go 1 doesn't support priority select cases, it is much tedious to >> implement the code >> satisfying the above listed requirements. The final implementation is >> often very ugly and inefficient. >> >> Does anyone else also experience the pain? >> >> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golan...@googlegroups.com <javascript:>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/golang-nuts/e3015cd8-c2ec-479e-927d-b9ad762d277e%40googlegroups.com >> >> <https://groups.google.com/d/msgid/golang-nuts/e3015cd8-c2ec-479e-927d-b9ad762d277e%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/15b4b573-ee9c-4552-be78-84b303173ad7%40googlegroups.com.
