panic: runtime error: index out of range in Go

Question

I have the following function that takes a command from terminal and prints something based on input. It seems simple enough, if the user types \'add\' the system prints a line,

Answer 1

You have to check the length of inp first:

func bootstrapCmd(c *commander.Command, inp []string) (err error) {
    if len(inp) == 0 {
        return errors.New("no input")
    }
    switch inp[0] {
    case "add":
        fmt.Println("you typed add")
    case "sub":
        fmt.Println("you typed sub")
    default:
        fmt.Println("invalid:", inp[0])
    }
    return nil

}