Document that tr() is not tr(1).

p4raw-id: //depot/cfgperl@5946

diff --git a/pod/perlop.pod b/pod/perlop.pod
index d847c99..174cf00 100644 (file)
--- a/pod/perlop.pod
+++ b/pod/perlop.pod
@@ -1225,6 +1225,12 @@ SEARCHLIST is delimited by bracketing quotes, the REPLACEMENTLIST has
 its own pair of quotes, which may or may not be bracketing quotes,
 e.g., C<tr[A-Z][a-z]> or C<tr(+\-*/)/ABCD/>.
 
+Note that C<tr> does B<not> do regular expression character classes
+such as C<\d> or C<[:lower:]>.  The <tr> operator is not equivalent to
+the tr(1) utility.  If you want to map strings between lower/upper
+cases, see L<perlfunc/lc> and L<perlfunc/uc>, and in general consider
+using the C<s> operator if you need regular expressions.
+
 Note also that the whole range idea is rather unportable between
 character sets--and even within character sets they may cause results
 you probably didn't expect.  A sound principle is to use only ranges