re.sub()和re.match()

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w = 'lllcooooc'

1.

>>> p = re.compile( r'c(.+)c' )
>>> re.sub(p,'',w)
'lll'

2.

>>> p = re.compile( r'c(.+)c' )

>>> matchObj = re.match( p, line)

None

3.

>>> p = re.compile( r'(.+)c(.+)c' )
>>> matchObj = re.match( p, line)
>>> matchObj.group()
'lllcooooc'
>>> matchObj.group(1)
'lll'

>>> matchObj.group(2)
'oooo'

3.5.

>>> p = re.compile( r'c(.+)c' )
>>> matchObj = re.match( p, line)
>>> matchObj.group(0)
'lllcooooc'
>>> matchObj.group()
'lllcooooc'
>>> matchObj.group(1)
'oooo'
>>> matchObj.group(2)
IndexError: no such group

>>> matchObj.groups(0)
('oooo',)
>>> matchObj.groups()
('oooo',)
>>> matchObj.groups(1)
('oooo',)
>>> matchObj.groups(2)
IndexError: no such group

4.

>>> p = re.compile( r'(.+)c(.+)c' )
>>> matchObj = re.match( p, line, re.M|re.I)
ValueError: Cannot process flags argument with a compiled pattern

5.

>>> matchObj = re.match( r'.*c(.*)c', line, re.M|re.I) 
>>> matchObj.group(0)
'lllcooooc'
>>> matchObj.group()
'lllcooooc'
>>> matchObj.group(1)
'oooo'
>>> matchObj.group(2)
IndexError: no such group