It does not protect C<$> or C<@>, so that variables can still be
substituted.
-C<\Q>, C<\L>, C<\U> and C<\E> are actually part of the syntax of regular
-expression I<literals>, and are not part of regexp syntax proper. So they
-do not work in interpolated patterns.
+C<\Q>, C<\L>, C<\l>, C<\U>, C<\u> and C<\E> are actually part of
+double-quotish syntax, and not part of regexp syntax proper. They will
+work if they appear in a regular expression embeddded directly in a
+program, but not when contained in a string that is interpolated in a
+pattern.
With the advent of 5.6.0, Perl regexps can handle more than just the
standard ASCII character set. Perl now supports I<Unicode>, a standard