go for range坑和闭包坑的分析
时间:2022-03-01 10:18:49|栏目:Golang|点击: 次
看程序:
package main import ( "fmt" "time" ) func main() { str := []string{"I","like","Golang"} for _, v := range str{ v += "good" } for k, v := range str{ fmt.Println(k, v) } time.Sleep(1e9) }
结果:
0 I
1 like
2 Golang
想一想,为什么。
再看:
package main import ( "fmt" "time" ) func main() { str := []string{"I","like","Golang"} for k, v := range str{ fmt.Println(&k, &v) } time.Sleep(1e9) }
结果:
0xc000012050 0xc00000e1e0
0xc000012050 0xc00000e1e0
0xc000012050 0xc00000e1e0
想一想,为什么。
再看:
package main import ( "fmt" "time" ) func main() { str := []string{"I","like","Golang"} for k, v := range str{ str = append(str, "good") fmt.Println(k, v) } time.Sleep(1e9) }
结果:
0 I
1 like
2 Golang
想一想, 为什么。
再看:
package main import ( "fmt" "time" ) func main() { str := []string{"I","like","Golang"} for k, v := range str{ go func(i int, s string){ fmt.Println(i, s, k, v) }(k, v) } time.Sleep(1e9) }
结果:
0 I 2 Golang
1 like 2 Golang
2 Golang 2 Golang
想一想,为什么。
最后再看:
package main import ( "fmt" "time" ) func main() { str := []string{"I","like","Golang"} for k, v := range str{ go func(i int, s string){ fmt.Println(i, s, k, v) }(k, v) time.Sleep(1e9) } time.Sleep(5e9) }
结果:
0 I 0 I
1 like 1 like
2 Golang 2 Golang
想一想,为什么。
不多说。
总结
栏 目:Golang
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本文标题:go for range坑和闭包坑的分析
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