TypeError:“NoneType”类型的参数不可迭代

时间:2014-05-01 22:01:53

标签: python python-2.7

我正在用Python制作一个Hangman游戏。在游戏中,一个python文件具有从数组中选择随机字符串并将其存储在变量中的函数。然后将该变量传递给另一个文件中的函数。该函数将用户猜测存储为变量中的字符串,然后检查该猜测是否在单词中。但是,每当我输入一个字母并按回车键时,我会在此问题的标题中收到错误。你知道,我正在使用Python 2.7。这是一个单词的函数代码:

import random

easyWords = ["car", "dog", "apple", "door", "drum"]

mediumWords = ["airplane", "monkey", "bananana", "window", "guitar"]

hardWords = ["motorcycle", "chuckwalla", "strawberry", "insulation", "didgeridoo"]

wordCount = []

#is called if the player chooses an easy game. 
#The words in the array it chooses are the shortest.
#the following three functions are the ones that
#choose the word randomly from their respective arrays.
def pickEasy():
    word = random.choice(easyWords)
    word = str(word)
    for i in range(1, len(word) + 1):
        wordCount.append("_")

#is called when the player chooses a medium game.
def pickMedium():
    word = random.choice(mediumWords)
    for i in range(1, len(word) + 1):
        wordCount.append("_")

#is called when the player chooses a hard game. 
def pickHard():
    word = random.choice(hardWords)
    for i in range(1, len(word) + 1):
        wordCount.append("_")

现在这里是用户猜测的代码,并确定它是否在为游戏选择的单词中(不要注意wordCount变量。另外,“words”是带有代码的文件的名称上文)):

from words import *
from art import *

def gamePlay(difficulty):
    if difficulty == 1:
        word = pickEasy()
        print start
        print wordCount
        getInput(word)

    elif difficulty == 2:
        word = pickMedium()
        print start
        print wordCount

    elif difficulty == 3:
        word = pickHard()
        print start
        print wordCount

def getInput(wordInput):
    wrong = 0
    guess = raw_input("Type a letter to see if it is in the word: \n").lower()

    if guess in wordInput:
        print "letter is in word"

    else:
        print "letter is not in word"

到目前为止,我已经尝试将gamePlay函数中的“guess”变量转换为带有str()的字符串,我尝试使用.lower()将其设置为小写,并且我在单词文件中做了类似的事情。这是我运行时得到的完整错误:

File "main.py", line 42, in <module>
    main()
  File "main.py", line 32, in main
    diff()
  File "main.py", line 17, in diff
    gamePlay(difficulty)
  File "/Users/Nathan/Desktop/Hangman/gameplay.py", line 9, in gamePlay
    getInput(word)
  File "/Users/Nathan/Desktop/Hangman/gameplay.py", line 25, in getInput
    if guess in wordInput:

你看到的“main.py”是我写的另一个python文件。如果你想看到其他人让我知道。但是,我觉得我展示的是唯一重要的。感谢您的时间!如果我遗漏了任何重要细节,请告诉我。

2 个答案:

答案 0 :(得分:15)

如果函数没有返回任何内容,例如:

def test():
    pass

它的隐含返回值为None

因此,由于您的pick*方法不返回任何内容,例如:

def pickEasy():
    word = random.choice(easyWords)
    word = str(word)
    for i in range(1, len(word) + 1):
        wordCount.append("_")

调用它们的行,例如:

word = pickEasy()

word设置为None,因此wordInput中的getInputNone。这意味着:

if guess in wordInput:

相当于:

if guess in None:

NoneNoneType的一个实例,它不提供迭代器/迭代功能,因此您会得到该类型错误。

修复是添加返回类型:

def pickEasy():
    word = random.choice(easyWords)
    word = str(word)
    for i in range(1, len(word) + 1):
        wordCount.append("_")
    return word

答案 1 :(得分:0)

python错误表明wordInput不是可迭代的 - &gt;它是NoneType。

如果您在违规行前打印wordInput,则会看到wordInputNone

由于wordInputNone,这意味着传递给函数的参数也是None。在这种情况下word。您将pickEasy的结果分配给word

问题是你的pickEasy函数没有返回任何内容。在Python中,一个没有返回任何内容的方法会返回一个NoneType。

我认为您想要返回word,这样就足够了:

def pickEasy():
    word = random.choice(easyWords)
    word = str(word)
    for i in range(1, len(word) + 1):
        wordCount.append("_")
    return word