Python正則表達式，用於查找具有多個變體的字符串的所有出現

Question

我找不到合適的正則表達式模式來匹配以下每個變體：

regular expression  
regular-expression  
regular:expression  
regular&expression   

我提供了以下字符串，我需要使用 findall() 方法來匹配上面列出的每個出現：

str="This is a string to search for a regular expression like regular expression or regular-expression or regular:expression or regular&expression"

Answer 1

import re
str= (
    'This is a string to search for a regular expression '
    'like regular expression or regular-expression or '
    'regular:expression or regular&expression'
)

r = re.compile(r'regular[- &:]expression')
print(r.findall(str))

結果：

['regular expression', 'regular expression',
'regular-expression', 'regular:expression',
'regular&expression']

Answer 2

正確的正則表達式將是“regular[-:&]expression”，如下所示

import re
search_string='''This is a string to search for a regular expression like regular 
expression or regular-expression or regular:expression or regular&expression'''

pattern = 'regular[-:&]expression'
match1= re.findall(pattern, search_string)
if match1 != None:
  print(pattern+' matched')
else:
  print(pattern+' did not match')

輸出：

 regular[-:&]expression matched 

Answer 3

這是通過以下方式完成的：

import re
search_string='''This is a string to search for a regular expression like regular 
expression or 
regular-expression or regular:expression or regular&expression'''
results1 = re.sub ("regular[ -:&]expression","regular expression", search_string)
print (results1)