and vertical whitespace characters.
The uppercase variants (C<\W>, C<\D>, C<\S>, C<\H>, and C<\V>) are
-character classes that match any character that isn't a word character,
-digit, whitespace, horizontal whitespace nor vertical whitespace.
+character classes that match, respectively, any character that isn't a
+word character, digit, whitespace, horizontal whitespace, or vertical
+whitespace.
Mnemonics: I<w>ord, I<d>igit, I<s>pace, I<h>orizontal, I<v>ertical.
=back
It is worth noting that C<\d>, C<\w>, etc, match single characters, not
-complete numbers or words. To match a number (that consists of integers),
+complete numbers or words. To match a number (that consists of digits),
use C<\d+>; to match a word, use C<\w+>.
=head3 \N