Bug #120605 for Regexp-Common: Escaped multi-character delimiters not recognised in balanced.pm

Consider these examples: say my $re = $RE{balanced}{-begin=>'<<'}{-end=>'>>'}; (?^:((?:\<\<(?:(?>[^\<\>]+)|\<(?!\<)|\>(?!\>)|(?-1))*\>\>))) '<< 3 > 1 >>' =~ $re; say $1; << 3 > 1 >> say $re =$RE{balanced}{-begin=>'\<\<'}{-end=>'\>\>'}; (?^:((?:\<(?:(?>[^\<\>]+)|(?-1))*\>))) '<< 3 > 1 >>' =~ $re; say $1; << 3 > 1 > The difference is that in the second the delimiters are backslash escaped (they were quotemetaed variables in my actual code) and suddenly the delimiters are considered to be `<` and `>` rather than `<<` and `>>`! If this is really the intended behavior then at least the documentation should mention it. I have tracked it down to lines 22 and 24 in balanced.pm. If the parentheses in `/([^|\\]+|\\.)+/gs` are made non-capturing the behavior would be the same as when the delimiters are not escaped. The `/g` ensures you get a list of all the pipe-delimited substrings anyway. I realize that even if this behavior is strange -- it becomes impossible to use delimiters which contain backslash or pipe -- it has seemingly been like this always so it might be too late to change it, but perhaps a flag `-allow_escapes` or some such would be possible?