Channel, goroutine. A goroutine is a method called in an asynchronous way. A method can be called as a goroutine with the go-keyword. This creates many possibilities.
With channels, we can return values from our asynchronous goroutines. We specify channels with the chan-keyword. We make channels with make.
Channel example. Let us combine these concepts into a simple program that makes sense. This program creates a channel named "c." The channel returns an int.
Here In this example we create a func and invoke it. We use the go-keyword to call it as a goroutine.
package main
import "fmt"
func main() {
// Make a channel that returns an int.
c := make(chan int)
// Call this func.
go func() {
// This does a long-running numerical computation.// ... It increments a number, then decrements it.
res := 0
for i := 0; i < 100; i++ {
for x := 0; x < 10000; x++ {
for z := 0; z < 10000; z++ {
res++
}
for z := 0; z < 10000; z++ {
res--
}
}
}
// Return the counter on the channel.
c <- res
}()
fmt.Println("HERE")
// Wait for result of func, store value in local.
res := <-c
fmt.Println("DONE")
fmt.Println("RESULT =", res)
}HERE
DONE
RESULT = 0
With asynchronous programs, we can better wield the power of modern computers. We can compute results faster. But some complexity is introduced.
In its modern design, Go has a good solution to asynchronous problems. With chan and goroutines (that use the go keyword) we run code on several threads at once.
Dot Net Perls is a collection of tested code examples. Pages are continually updated to stay current, with code correctness a top priority.
Sam Allen is passionate about computer languages. In the past, his work has been recommended by Apple and Microsoft and he has studied computers at a selective university in the United States.
This page was last updated on Nov 27, 2023 (edit).