docs: fix channel select example (#10213)
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539594bfce
commit
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63
doc/docs.md
63
doc/docs.md
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@ -2885,29 +2885,48 @@ y := <-ch2 ?
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The `select` command allows monitoring several channels at the same time
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without noticeable CPU load. It consists of a list of possible transfers and associated branches
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of statements - similar to the [match](#match) command:
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```v wip
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```v
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import time
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fn main () {
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c := chan f64{}
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ch := chan f64{}
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ch2 := chan f64{}
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ch3 := chan f64{}
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mut b := 0.0
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// ...
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select {
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a := <-ch {
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// do something with `a`
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}
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b = <-ch2 {
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// do something with predeclared variable `b`
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}
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ch3 <- c {
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// do something if `c` was sent
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}
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> 500 * time.millisecond {
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// do something if no channel has become ready within 0.5s
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}
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}
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fn main() {
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ch := chan f64{}
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ch2 := chan f64{}
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ch3 := chan f64{}
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mut b := 0.0
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c := 1.0
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// ... setup go threads that will send on ch/ch2
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go fn (the_channel chan f64) {
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time.sleep(5 * time.millisecond)
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the_channel <- 1.0
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}(ch)
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go fn (the_channel chan f64) {
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time.sleep(1 * time.millisecond)
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the_channel <- 1.0
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}(ch2)
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go fn (the_channel chan f64) {
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_ := <-the_channel
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}(ch3)
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//
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select {
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a := <-ch {
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// do something with `a`
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eprintln('> a: $a')
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}
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b = <-ch2 {
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// do something with predeclared variable `b`
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eprintln('> b: $b')
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}
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ch3 <- c {
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// do something if `c` was sent
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time.sleep(5 * time.millisecond)
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eprintln('> c: $c was send on channel ch3')
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}
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> 500 * time.millisecond {
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// do something if no channel has become ready within 0.5s
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eprintln('> more than 0.5s passed without a channel being ready')
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}
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}
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eprintln('> done')
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}
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```
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