=head1 Core Enhancements
-XXX New core language features go here. Summarize user-visible core language
-enhancements. Particularly prominent performance optimisations could go
-here, but most should go in the L</Performance Enhancements> section.
-
-[ List each enhancement as a =head2 entry ]
-
=head2 Interpolations now Accepted in Regular Expression Set Operations
Perl v5.17.8 introduced L<regular expression set operations|perlre/(?[ ])>.
...
qr/(?[ \p{Digit} & $thai_or_lao ])/;
-=head1 Security
-
-XXX Any security-related notices go here. In particular, any security
-vulnerabilities closed should be noted here rather than in the
-L</Selected Bug Fixes> section.
-
-[ List each security issue as a =head2 entry ]
-
=head1 Incompatible Changes
=head2 C<$ENV{foo} = undef> no longer deletes value from environ
=back
-=head2 Removed Modules and Pragmata
-
-=over 4
-
-=item *
-
-XXX
-
-=back
-
=head1 Documentation
-XXX Changes to files in F<pod/> go here. Consider grouping entries by
-file and be sure to link to the appropriate page, e.g. L<perlfunc>.
-
-=head2 New Documentation
-
-XXX Changes which create B<new> files in F<pod/> go here.
-
-=head3 L<XXX>
-
-XXX Description of the purpose of the new file here
-
=head2 Changes to Existing Documentation
=head3 L<perlsec>
contains. (The name C<av_top> which was introduced in Perl v.5.17.8 has
been removed.)
-XXX
-
=back
=head1 Selected Bug Fixes