Question

我正在学习使用Learn Python编写代码。我得到了一个＆＃34; valueError＆＃34;在Ex 41中，我似乎无法弄清楚原因。我已经使用python内置的调试器导入PDB搜索了如何调试代码，但我仍然无法弄清楚错误。我已经根据教科书中的代码对我的代码进行了三次检查，确切地说。

这是我得到的错误：

Traceback (most recent call last):
  File "ex41.py", line 72, in <module>
    question, answer = convert(snippet, phrase)
ValueError: not enough values to unpack (expected 2, got 0)

这是抛出的代码的一部分：

    # keep going until they hit CTRL-D
try:
    while True:
        snippets = list(PHRASES.keys())
        random.shuffle(snippets)
        for snippet in snippets:
            phrase = PHRASES[snippet]
            question, answer = convert(snippet, phrase)
            if PHRASE_FIRST:
                question, answer = answer, question

            print(question)

            input("> ")
            print(f"ANSWER: {answer}\n\n" )
    except EOFError:
        print("\nBye")

练习的整个代码低于减去错误的代码。

import random
from urllib.request import urlopen
import sys

WORD_URL = "http://learncodethehardway.org/words.txt"
WORDS = []

PHRASES = {
    "class %%%(%%%):":
      "Make a class named %%% tht is-a %%%.",
    "class %%%(object):\n\tdef __init__(self, ***)" :
      "class %%% has-a __init__ that takes self and *** params.",
    "class %%%(object):\n\tdef ***(self, @@@)":
      "class %%% has-a function *** that takes self and @@@ params.",
    "*** = %%%()":
      "Set *** to an instance of class %%%.",
    "***.*** (@@@)":
      "From *** get the *** function, call it with params self, @@@.",
    "***.*** = '***'":
      "From *** get the *** attribute and set it to '***'." 
}

# do the want to drill phrases first
if len(sys.argv) == 2 and sys.argv[1] == "english":
    PHRASE_FIRST = True
else:
    PHRASE_FIRST = False

# load up the words from the website
for word in urlopen(WORD_URL).readlines():
    WORDS.append(str(word.strip(), encoding="utf-8"))


def convert(snippet, phrase):
    class_names = [w.capitalize() for w in 
                    random.sample(WORDS, snippet.count("%%%"))]
    other_names = random.sample(WORDS, snippet.count("***"))
    results = []
    param_names = []

    for i in range(0, snippet.count("@@@")):
        param_count = random.randint(1,3)
        param_names.append(', '.join(
            random.sample(WORDS, param_count)))

    for sentence in snippet, phrase:
        result = sentence[:]

        # fake class names
        for word in class_names:
            result = result.replace("%%%", word, 1)

        # fake other names
        for word in other_names:
            result = result.replace("***", word, 1)

        # fake parameter lists
        for word in param_names:
            result = result.replace("@@@", word, 1)

            results.append(result)

    return results

Answer 1

此问题是由于第61行“results.append（result）”引起的，它应该缩小一个块。

学习python中的python valueerror艰难的方式Ex41

1 个答案: