DateTime bug?

[montanaro at tttech.com]

    Carsten> I'm using Python 2.2 with the eGenix MX extensions 2.0.3. It seems the
    Carsten> DateTime module has a bug:

    ...
    Carsten> sre_constants.error: redefinition of group name 'sign' as group
    Carsten> 7; was group 3

The sre package was tightened up for 2.2 to raise an error if the same named
group was present more than once in a regular expression.  Here's 2.1:

    % python
    Python 2.1.1 (#1, Dec 12 2001, 09:47:33) 
    [GCC 2.96 20000731 (Mandrake Linux 8.1 2.96-0.62mdk)] on linux2
    Type "copyright", "credits" or "license" for more information.
    >>> import re
    >>> re.compile(r"(?P<g1>[ab])(?P<g1>[cd])")
    <SRE_Pattern object at 0x8180d90>

and 2.2:

    % python
    Python 2.2+ (#45, Jan  8 2002, 20:30:28) 
    [GCC 2.96 20000731 (Mandrake Linux 8.1 2.96-0.62mdk)] on linux2
    Type "help", "copyright", "credits" or "license" for more information.
    import re
    >>> import re
    >>> re.compile(r"(?P<g1>[ab])(?P<g1>[cd])")
    Traceback (most recent call last):
      File "<stdin>", line 1, in ?
      File "/usr/local/lib/python2.2/sre.py", line 178, in compile
	return _compile(pattern, flags)
      File "/usr/local/lib/python2.2/sre.py", line 228, in _compile
	raise error, v # invalid expression
    sre_constants.error: redefinition of group name 'g1' as group 2; was group 1

Because of the way regular expressions were built up out of smaller
fragments, mx.DateTime frequently repeated the same named group within a
single regular expression.  I believe Marc-André Lemburg has released a new
version that does not rely on this.

-- 
Skip Montanaro (skip at pobox.com - http://www.mojam.com/)