regex.compile("a(?x: b c )d") causes "_regex_core.error: missing )"

What steps will reproduce the problem?
>>> import regex
>>> regex.compile("a(?x: b c )d")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python32\3.2.2\lib\site-packages\regex.py", line 289, in compile
    return _compile(pattern, flags, kwargs)
  File "C:\Python32\3.2.2\lib\site-packages\regex.py", line 423, in _compile
    parsed = parse_pattern(source, info)
  File "C:\Python32\3.2.2\lib\site-packages\_regex_core.py", line 339, in parse_
pattern
    branches = [parse_sequence(source, info)]
  File "C:\Python32\3.2.2\lib\site-packages\_regex_core.py", line 358, in parse_
sequence
    item = parse_item(source, info)
  File "C:\Python32\3.2.2\lib\site-packages\_regex_core.py", line 368, in parse_
item
    element = parse_element(source, info)
  File "C:\Python32\3.2.2\lib\site-packages\_regex_core.py", line 660, in parse_
element
    element = parse_paren(source, info)
  File "C:\Python32\3.2.2\lib\site-packages\_regex_core.py", line 796, in parse_
paren
    return parse_flags_subpattern(source, info)
  File "C:\Python32\3.2.2\lib\site-packages\_regex_core.py", line 1014, in parse
_flags_subpattern
    source.expect(")")
  File "C:\Python32\3.2.2\lib\site-packages\_regex_core.py", line 3439, in expec
t
    raise error("missing {}".format(substring))
_regex_core.error: missing )
>>>

What is the expected output? What do you see instead?
>>> import regex
>>> regex.compile("a(?x: b c )d")
regex.Regex('a(?x: b c )d', flags=regex.V0)
>>> regex.search("a(?x: b c )d", "abcd").group(0)
'abcd'
>>>

What version of the product are you using? On what operating system?
Windows XP Home SP3 (32-bit version)
Python 3.2.2 (default, Sep  4 2011, 09:51:08) [MSC v.1500 32 bit (Intel)] on win
32
regex 0.1.20120122

Please provide any additional information below.

Original issue reported on code.google.com by msm...@gmail.com on 22 Jan 2012 at 8:51

Forever-Young / mrab-regex-hg

regex.compile("a(?x: b c )d") causes "_regex_core.error: missing )" #46