Question

I have been playing around with regular expressions and was trying to subclass the MatchObject that is returned from re.search.

I have had no luck getting access to the MatchObject class.

I assume enter code herethat the actual type of this object is not called “MatchObject”:

>>> re.search ("a", "a")
<_sre.SRE_Match object at 0x100427a58>

However, I am not able get access to this object:

import _sre

dir (_sre)
['CODESIZE', 'MAGIC', '__doc__', '__name__', '__package__', 'compile', 'copyright', 'getcodesize', 'getlower']

>>> dir(_sre.SRE_Match)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'SRE_Match'

What am I missing?

Answer 1

It’s not gonna happen 🙂

>>> import re
>>> mo = re.search ("a", "a")
>>> mo_class = type(mo)
>>> mo_class
<type '_sre.SRE_Match'>
>>> class SubClass(mo_class):
...     pass
... 
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: Error when calling the metaclass bases
    type '_sre.SRE_Match' is not an acceptable base type

It’s worth noting that you can always get access to the type of an object by calling type(obj) though.