Question

我有一个正则表达式，但我希望将它们组合成单个表达式而不影响输出。下面的代码保存文本中的单词列表并保存到列表中。

import re
a=[]
with open('qwert.txt', 'r') as f:
    for line in f:
        res = re.findall(r'(?:Prof[.](\w+))', line)
        if res: 
            a.extend(res)
        res = re.findall(r'(?:As (\w+))', line)
        if res:
            a.extend(res)
        res = re.findall(r'\w+(?==\w)', line)
        if res:
            a.extend(res)

print a

qwert.txt

As every
prof.John and Prof.Keel and goodthing=him
Prof.Tensa
Keel a good person As kim
kim is fine
Prof.Jees
As John winning Nobel prize
As Mary wins all prize
sa for ask
car

he=is good

输出：

['every', 'Keel', 'goodthing', 'Tensa', 'kim', 'Jees', 'John', 'Mary', 'he']

如何将三个正则表达式stmts放在一行？

Answer 1

你可以使用运算符＆＃34; |＆＃34;，它允许你找到一个或另一个表达式。 res = re.findall(r'(?:Prof[.](\w+))|(?:As (\w+))|(?:\w+(?==\w))', line)

Answer 2

您需要将最后\w+内部捕获组封闭，并且还需要启用多行修改器。

>>> import re
>>> a=[]
>>> with open('qwert.txt', 'r') as f:
...     for line in f:
...         res = re.findall(r'(?:Prof[.](\w+))|(?:As (\w+))|(\w+)(?==\w)', line, re.M)
...         if res:
...             a.extend(res)
... 
>>> a
[('', 'every', ''), ('Keel', '', ''), ('', '', 'goodthing'), ('Tensa', '', ''), ('', 'kim', ''), ('Jees', '', ''), ('', 'John', ''), ('', 'Mary', ''), ('', '', 'he')]

或

没有任何捕获组，

>>> import re >>> a=[] >>> with open('qwert.txt', 'r') as f: ... for line in f: ... res = re.findall(r'(?<=Prof[.])\w+|(?<=As )\w+|\w+(?==\w)', line, re.M) ... if res: ... a.extend(res) ... >>> a ['every', 'Keel', 'goodthing', 'Tensa', 'kim', 'Jees', 'John', 'Mary', 'he']

python正则表达式语句在一行上

2 个答案: