This is an open source project to learn golang
package main
import (
"context"
"log"
"sync"
"time"
)
func HelloWorld() {
time.Sleep(time.Second)
log.Println("Hello, World!")
}
func HelloWorld2() {
c := make(chan struct{})
go func() {
time.Sleep(time.Second)
log.Println("Hello, World chan!")
c <- struct{}{}
}()
<-c
}
func HelloWorld3() {
var g sync.WaitGroup
g.Add(1)
go func(){
time.Sleep(time.Second)
log.Println("Hello, World WaitGroup!")
g.Done()
}()
g.Wait()
}
func HelloWorld4() {
cond := sync.NewCond(new(sync.Mutex))
go func() {
time.Sleep(time.Second)
log.Println("Hello, World Cond!")
cond.Signal()
}()
cond.L.Lock()
cond.Wait()
cond.L.Unlock()
}
func HelloWorld5() {
ctx, cancel := context.WithCancel(context.Background())
go cancel()
select {
case <-ctx.Done():
time.Sleep(time.Second)
log.Println("Hello, World WithCancel!")
}
}
func main() {
HelloWorld()
HelloWorld2()
HelloWorld3()
HelloWorld4()
HelloWorld5()
}