我知道这本备受批评的书中有很多关于这个练习的帖子,但到目前为止它帮助我开始理解这些内容。
但是,每一章都有问题,而有些我可以自己回答,有些则更复杂。
import random
from urllib import urlopen
import sys
WORD_URL = "http://learncodethehardway.org/words.txt"
WORDS = []
PHRASES = {
"class %%%(%%%):":
"Make a class named %%% that is-a %%%.",
"class %%%(object):\n\tdef __init__(self, ***)" :
"class %%% has-a __init__ that takes self and *** parameters.",
"class %%%(object):\n\tdef ***(self, @@@)":
"class %%% has-a function named *** that takes self and @@@ parameters.",
"*** = %%%()":
"Set *** to an instance of class %%%.",
"***.***(@@@)":
"From *** get the *** function, and call it with parameters self, @@@.",
"***.*** = '***'":
"From *** get the *** attribute and set it to '***'."
}
# do they want to drill phrases first
PHRASE_FIRST = False
if len(sys.argv) == 2 and sys.argv[1] == "english":
PHRASE_FIRST = True
# load up the words from the website
for word in urlopen(WORD_URL).readlines():
WORDS.append(word.strip())
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
# keep going until they hit CTRL-D
try:
while True:
snippets = 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
raw_input("> ")
print "ANSWER: %s\n\n" % answer
except EOFError:
print "\nBye"
我不明白这一点
for sentence in snippet, phrase:
result = sentence[:]
句子[:]假设做什么?我在没有[:]的情况下尝试了代码并且它有效,所以我很困惑。也许只是因为没有reasong让事情变得更加混乱?因为我也注意到了,
此代码:
for i in range(0, snippet.count("@@@")):
param_count = random.randint(1,3)
param_names.append(', '.join(random.sample(WORDS, param_count)))
我可以重写一些不那么令人困惑的东西param_names = random.sample(WORDS, snippet.count("@@@"))
,这也引出了为什么这样做的问题?
很抱歉n00bish的帖子,但帮助意味着很多!