Question

我有一个很长的正则表达式，有许多替换，我希望能够用正则表达式替换正则表达式中的每个匹配，后跟一个新行（＆＃39; \ n＆＃39;）。

使用re.sub（）最有效的方法是什么？

这是一个简单的例子：

s = 'I want to be able to replace many words, especially in this sentence, since it will help me solve by problem. That makes sense right?'

pattern = re.compile(r'words[,]|sentence[,]|problem[.]')

for match in matches:
    re.sub(pattern, match + '\n', match)

我知道这个for循环不起作用，我只是希望澄清我在这里要解决的问题。在此先感谢您的帮助。我可能会遗漏一些非常简单的事情。

Answer 1

要替换整个匹配项，您可以使用替换反向引用\g<0>。但是，您希望将变量替换并存储在变量中。您需要将回调方法作为替换参数传递给re.sub，并返回整个匹配值（match.group()），并在该值附加换行符：

import re
matches = []                          # Variable to hold the matches
def repl(m):                          # m is a match data object
    matches.append(m.group())         # Add a whole match value
    return "{}\n".format(m.group())   # Return the match and a newline appended to it

s = 'I want to be able to replace many words, especially in this sentence, since it will help me solve by problem. That makes sense right?'
pattern = re.compile(r'words[,]|sentence[,]|problem[.]')
s = re.sub(pattern, repl, s)

print(s)
print(matches)

请参阅Python demo

Answer 2

就像这样？

    text ='I want to be able to replace many words, especially in this sentence, since it will help me solve by problem. That makes sense right?'
    text_list = tex t.replace('.',',').strip(',|.|?').split(',')
    ##Remove the beginning and end symbols.And split by ','
    print (text_list)
    for i in text_list:
        ii=i.split(',')
        print(ii)

结果

    ['I want to be able to replace many words', ' especially in this sentence', ' since it will help me solve by problem', ' That makes sense right']
    ['I want to be able to replace many words']
    [' especially in this sentence']
    [' since it will help me solve by problem']
    [' That makes sense right']

Answer 3

re.sub 的第二个参数可以是一个字符串，也可以是一个接受匹配实例并返回一个字符串的可调用对象。这样做

def break_line(match):
    return "\n" + match.group()

text = re.sub(pattern, break_line, text)

Python正则表达式将每个匹配替换为自身以及新行

3 个答案: