their builtin one. Note also that, if you have a package called C<m>,
C<s>, or C<y>, then you can't use the qualified form of an identifier
because it will be interpreted instead as a pattern match, a substitution,
-or a translation.
+or a transliteration.
(Variables beginning with underscore used to be forced into package
main, but we decided it was more useful for package writers to be able