9a54ee4241
Instead of storing the value to send/receive in the coroutine promise, store only a pointer in the promise. This simplifies the code a lot and allows larger value sizes to be sent across a channel. Unfortunately, this new system has a code size impact. For example, compiling testdata/channel.go for the BBC micro:bit, there is an increase in code size from 4776 bytes to 4856 bytes. However, the improved flexibility and simplicity of the code should be worth it. If this becomes an issue, we can always refactor the code at a later time.
122 строки
1,8 КиБ
Go
122 строки
1,8 КиБ
Go
package main
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import "time"
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func main() {
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ch := make(chan int)
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println("len, cap of channel:", len(ch), cap(ch))
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go sender(ch)
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n, ok := <-ch
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println("recv from open channel:", n, ok)
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for n := range ch {
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if n == 6 {
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time.Sleep(time.Microsecond)
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}
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println("received num:", n)
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}
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n, ok = <-ch
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println("recv from closed channel:", n, ok)
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// Test bigger values
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ch2 := make(chan complex128)
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go sendComplex(ch2)
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println("complex128:", <-ch2)
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// Test multi-sender.
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ch = make(chan int)
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go fastsender(ch)
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go fastsender(ch)
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go fastsender(ch)
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slowreceiver(ch)
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// Test multi-receiver.
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ch = make(chan int)
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go fastreceiver(ch)
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go fastreceiver(ch)
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go fastreceiver(ch)
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slowsender(ch)
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// Test iterator style channel.
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ch = make(chan int)
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go iterator(ch, 100)
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sum := 0
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for i := range ch {
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sum += i
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}
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println("sum(100):", sum)
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// Test select
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go selectDeadlock()
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go selectNoOp()
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// Allow goroutines to exit.
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time.Sleep(time.Microsecond)
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}
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func sender(ch chan int) {
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for i := 1; i <= 8; i++ {
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if i == 4 {
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time.Sleep(time.Microsecond)
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println("slept")
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}
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ch <- i
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}
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close(ch)
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}
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func sendComplex(ch chan complex128) {
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ch <- 7+10.5i
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}
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func fastsender(ch chan int) {
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ch <- 10
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ch <- 11
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}
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func slowreceiver(ch chan int) {
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for i := 0; i < 6; i++ {
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n := <-ch
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println("got n:", n)
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time.Sleep(time.Microsecond)
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}
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}
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func slowsender(ch chan int) {
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for n := 0; n < 6; n++ {
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time.Sleep(time.Microsecond)
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ch <- 12 + n
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}
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}
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func fastreceiver(ch chan int) {
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sum := 0
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for i := 0; i < 2; i++ {
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n := <-ch
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sum += n
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}
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println("sum:", sum)
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}
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func iterator(ch chan int, top int) {
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for i := 0; i < top; i++ {
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ch <- i
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}
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close(ch)
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}
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func selectDeadlock() {
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println("deadlocking")
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select {}
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println("unreachable")
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}
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func selectNoOp() {
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println("select no-op")
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select {
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default:
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}
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println("after no-op")
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}
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