Golang channel为什么不会阻塞的原因详解

package main
import "fmt"
func main() {
    chanInt := make(chan int)
    Go func() {
        chanInt <- 100
    }()
    res := <-chanInt
    fmt.Println(res)
}

package main
import "fmt"
func hello() {
    fmt.Println("Hello Goroutine!")
}
func main() {
    go hello() // 启动另外一个goroutine去执行hello函数
    fmt.Println("main goroutine done!")
}

package main
import (
    "fmt"
    "time"
)
func main() {
    chanInt := make(chan int)
    go func() {
        chanInt <- 100
    }()
    time.Sleep(10 * time.Second)
    res := <-chanInt
    fmt.Println(res)
}

func main() {
    chanInt := make(chan int)
    chanInt <- 100
    res := <-chanInt
    fmt.Println(res)
}