=item *
+A single hexadecimal number denoting a Unicode code point to include.
+
+=item *
+
Two hexadecimal numbers separated by horizontal whitespace (space or
tabular characters) denoting a range of Unicode code points to include.
It's important to remember not to use "&" for the first set -- that
would be intersecting with nothing (resulting in an empty set).
-A final note on the user-defined property tests: they will be used
-only if the scalar has been marked as having Unicode characters.
-Old byte-style strings will not be affected.
-
=head2 User-Defined Case Mappings
You can also define your own mappings to be used in the lc(),