David Ellsworth added the comment:
Thanks, I didn't realize. I thought it was an official module that wasn't
included as part of the main package due to being unfinished.
Reported the bug here:
https://bitbucket.org/mrabarnett/mrab-regex/issues/408/regex-fails-with-a-
New submission from David Ellsworth :
The regex /^((x*)\2{3}(?=\2$))*x$/ matches powers of 5 in unary, expressed as
strings of "x" characters whose length is the number.
The following command line should print "1", but prints nothing:
python -c 'import regex; regex
