id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	difficulty
345	utf8 regexp bug with underscores	Jim Ursetto	sjamaan	"Only in utf8 mode, regexp seems to have a bug with negated charsets containing underscores in either POSIX REs or SREs.  I'm not sure but I think any charset with one underscore and one or more other chars is affected.

Irregex has the same problem but only when called with option 'utf8.

I'm using chicken-experimental 4.5.8 without irregex 0.8, so perhaps this bug is fixed in irregex 0.8?  I haven't checked.  I know this occurs back to Chicken 4.5.0 at least.
{{{
#;> (use utf8)
#;> (regexp ""[^_]"")
#<regexp>
#;> (regexp ""[^a_b]"")
Error: (cddr) bad argument type: ()
#;> (regexp ""[^a_]"")
Error: (cddr) bad argument type: ()
#;> (regexp ""[^_a]"")
Error: (cddr) bad argument type: ()
#;> (regexp '(~ #\_ #\a))
Error: (cddr) bad argument type: ()

#;> (irregex '(~ #\_ #\a))
#(*irregex-tag* ...)
#;> (irregex '(~ #\_ #\a) 'utf8)
Error: (cddr) bad argument type: ()

}}}"	defect	closed	minor	4.9.0	core libraries	4.5.x	wontfix