the problem.
However, on earlier Perls, or if you pass strings to subroutines outside
-the feature's scope, you can force Unicode semantics by changing the
+the feature's scope, you can force Unicode rules by changing the
encoding to UTF-8 by doing C<utf8::upgrade($string)>. This can be used
safely on any string, as it checks and does not change strings that have
already been upgraded.