-C<qr/[\N{named sequence}]/> now works properly in many instances. Some
-names known to C<\N{...}> refer to a sequence of multiple characters,
-instead of the usual single character. Bracketed character classes
-generally only match single characters, but now special handling has
-been added so that they can match named sequences, but not if the class
-is inverted or the sequence is specified as the beginning or end of a
-range. In these cases, the only behavior change from before is a slight
-rewording of the fatal error message given when this class is part of a
-C<?[...])> construct. When the C<[...]> stands alone, the same
-non-fatal warning as before is raised, and only the first character in
-the sequence is used, again just as before.