Question

我理解错误，但我尝试向其添加if语句。

def repeat():
    message = input("command: ").split(" ")
    if len(message) == 2: #if there is a first parameter 
        cmd,param = message #add it to the message
    elif len(message) == 3: #if there is a first and second parameter
        cmd,param,param2 = message #add it to the message
    else: #if there is no first and second parameter
        cmd = message #add just the command to the message
    if cmd == "local":
        if len(message) == 2 or len(message) == 3: #if there is a first or second parameter
            print("error: no first or second parameter in command 'local'") #error
            repeat()
        else: #if there are no parameters
            print("test") #execute the command
            repeat()
    else:
        print("unrecognized command")
        repeat()
repeat()

编辑：当我向命令添加第二个参数时，本地＆＃39;它在第11行返回错误，但是当我没有添加第一个或第二个参数时，它会打印＆＃34;无法识别的命令＆＃34;在第17行使用。

Answer 1

您的代码写得不太好，您应该更好地制定您的问题，但我已经修复了错误。

def repeat():
    message = input("command: ").split(" ")

    #correction starts here
    lenght = len(message)
    param = False
    param2 = False
    if lenght == 1:
        cmd = message[0]
    elif lenght == 2:
        cmd = message[0]
        param = message[1]
    elif lenght == 3:
        cmd = message[0]
        param = message[1]
        param2 = message[2]
    else:
        repeat()
   #correction ends here


    if cmd == "local":
        if param: #if there is at least one parameter
            print("error: no first or second parameter in command 'local'") #error
        else: #if there are no parameters
            print(message) #execute the command
        repeat()
    if cmd == "print":
        if param2: #if there is a second parameter
            print("error: no second parameter in command 'print'") #error
        elif param: #if there is only one parameter
            print(message) #print only the first parameter (example: print test would output 'test')
        repeat()
repeat()

（编辑）ValueError：没有足够的值来解压缩（预期3，得到2），尝试向其添加if语句

1 个答案: