golang隨機time.sleep的Duration問題

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碰到一個Golang time.Sleep()的問題，這golang的time.sleep的功能貌似要比python ruby都要精細些，python的等待只是time.sleep()而已，而golang可以time.Sleep(10 * time.Second) 毫秒、秒分時等不同日期來搞… 大事不幹，淨整些沒用的…  

該文章寫的有些亂，歡迎來噴 ! 另外文章後續不斷更新中，請到原文地址查看更新http://xiaorui.cc/?p=3034

重現一下問題，用math/rannd得到10以內的隨機數，然後time.sleep()等待…

Pythonnum := rand.Int31n(10)time.sleep(num * time.Second)

123	num := rand.Int31n(10)time.sleep(num * time.Second)

會遇到下面的問題:

Python#xiaorui.cc# command-line-arguments./lock.go:88: invalid operation: int(DefaultTimeout) * time.Second (mismatched types int and time.Duration)

1234	#xiaorui.cc# command-line-arguments./lock.go:88: invalid operation: int(DefaultTimeout) * time.Second (mismatched types int and time.Duration)

解決的方法:
    

Pythontime.Sleep(time.Duration(num) * time.Second)

12	time.Sleep(time.Duration(num) * time.Second)

期初原因以為是rand隨機數有問題，簡單看了rand的函數說明感覺沒問題！ 下面是產生的原因:

Pythonfunc Sleep(d Duration) Sleep pauses the current goroutine for at least the duration d. A negative or zero duration causes Sleep to return immediately.

123	func Sleep(d Duration)    Sleep pauses the current goroutine for at least the duration d. A negative or zero duration causes Sleep to return immediately.

int32 and time.Duration are different types. You need to convert the int32 to a time.Duration, such as time.Sleep(time.Duration(rand.Int31n(1000)) * time.Millisecond).

下面是個完整的golang隨機數，然後time.sleep()的例子:

Pythonpackage mainimport ( "fmt" "math/rand" "time")func main() { rand.Seed(time.Now().UnixNano()) for i := 0; i < 10; i++ { x := rand.Intn(10) fmt.Println(x) time.Sleep(time.Duration(x) * time.Second) }}

1234567891011121314151617

package main import (    "fmt"    "math/rand"    "time") func main() {    rand.Seed(time.Now().UnixNano())    for i := 0; i < 10; i++ {        x := rand.Intn(10)        fmt.Println(x)        time.Sleep(time.Duration(x) * time.Second)    }}

Golang的time.sleep雖然可以直接用數字，但不能是float浮點型.

Pythontime.Sleep(1 * time.Second) //可以time.Sleep(1.1 * time.Second) //BUGtime.Sleep(time.Duration(yourTime) * time.Second) //可以

1234	time.Sleep(1 * time.Second)  //可以time.Sleep(1.1 * time.Second) //BUGtime.Sleep(time.Duration(yourTime) * time.Second) //可以

提示的錯誤是, constant 1.1 truncated to integer 。至於原因到這裡看 https://golang.org/pkg/time/#Duration