在下面的示例中，為什么在“Bonjour”之前打印“Greetings done”？發送例程不應該等到接收例程收到通道中的值嗎？package mainimport (    "fmt")func greetings(c chan string) {    fmt.Println(<-c)    c <- "Bonjour"    fmt.Println("Greetings done")}func main() {    myChannel := make(chan string)    // creates routine and leaves it upto Go to execute    go greetings(myChannel)    // while greetings() routine is getting executed, a new value is written to channel by main function    myChannel <- "hi from main"    // now main function (sender routine) is blocked. It wont proceed until another routine reads from the channel    // By then greetings() routine will read the value and prints it. Hence "hi from main" gets printed    // Now main function proceeds and moves to next line    // simultaneously, greetings() would have written "Bonjour" to channel    // main routine will receive it and prints it    fmt.Println(<-myChannel)    fmt.Println("main done")}該程序的輸出是：hi from mainGreetings doneBonjourmain done發送例程不應該等到接收例程收到通道中的值嗎？意思是不應該在“Bonjour”之后打印“Greetings done”嗎？因為發送例程（問候語）將被阻塞，直到主例程收到它的值。