python3.x正则表达式的含义及使用

import re

import nltk

#正则表达式

wordlist = [w for w in nltk.corpus.words.words('en') if w.islower()]

print(wordlist)

#查找ed结尾的词汇

print([w for w in wordlist if re.search('ed$', w)])

#匹配：8个字母，第3个字母是j，第6个字母是t

print([w for w in wordlist if re.search('^..j..t..$', w)])

#9宫格输入判断

print([w for w in wordlist if re.search('^[ghi][mno][jlk][def]$', w)])

#正则表达式中的+

chat_words = sorted(set(w for w in nltk.corpus.nps_chat.words()))

print([w for w in chat_words if re.search('^m+i+n+e+$', w)])

print([w for w in chat_words if re.search('^[ha]+$', w)])

wsj = sorted(set(nltk.corpus.treebank.words()))

print([w for w in wsj if re.search('^[0-9]+\.[0-9]+$', w)])

print([w for w in wsj if re.search(r'^[A-Z]+\$$', w)])

print([w for w in wsj if re.search('^[0-9]{4}$', w)])

print([w for w in wsj if re.search('^[0-9]+-[a-z]{3,5}$', w)])

print([w for w in wsj if re.search('^[a-z]{5,}-[a-z]{2,3}-[a-z]{,6}$', w)])
print([w for w in wsj if re.search('(ed|ing)$', w)])