panic：运行时错误：切片范围超出范围

Question

我正在关注本教程：https://gobyexample.com/slices

我在中间：

package main

import "fmt"

func main() {

    s := make([]string, 3)
    fmt.Println("emp:", s)

    s[0] = "a"
    s[1] = "b"
    s[2] = "c"
    fmt.Println("set:", s)

    c := make([]string, len(s))
    copy(c, s)
    fmt.Println("copy:", c)

    l := s[2:5]
    fmt.Println("sl1:", l)
}

当我突然遇到这个错误时：

alex@alex-K43U:~/golang$ go run hello.go
emp: [  ]
set: [a b c]
copy: [a b c]
panic: runtime error: slice bounds out of range

goroutine 1 [running]:
main.main()
    /home/alex/golang/hello.go:19 +0x2ba

goroutine 2 [syscall]:
created by runtime.main
    /usr/lib/go/src/pkg/runtime/proc.c:221
exit status 2

这是什么意思？教程错了吗？我该怎么做才能解决它？

Answer 1

您忘记了append增长s的部分。

s = append(s, "d")
s = append(s, "e", "f")
fmt.Println("apd:", s)

Answer 2

您的代码省略了原始示例中的这些行：

s = append(s, "d")
s = append(s, "e", "f")

没有这些行，len（s）== 3.