Clarify warning that e.g. \q is reserved

Currently the meaning of e.g. \q is simply 'q', with a warning
generated.  Elsewhere it is documented that this means that \q is
thus a reserved term, available for Perl to co-opt in some future
release.  But the warning doesn't say that.  Clarify it.

diff --git a/pod/perldiag.pod b/pod/perldiag.pod
index 3963e7e..f80bdcd 100644 (file)
--- a/pod/perldiag.pod
+++ b/pod/perldiag.pod
@@ -4522,19 +4522,21 @@ to run a compressed script, a binary program, or a directory as a Perl program.
 
 (W regexp) You used a backslash-character combination which is not
 recognized by Perl inside character classes.  The character was
-understood literally.
+understood literally, but this may change in a future version of Perl.
 The <-- HERE shows in the regular expression about where the
 escape was discovered.
 
 =item Unrecognized escape \\%c passed through
 
 (W misc) You used a backslash-character combination which is not
-recognized by Perl.  The character was understood literally.
+recognized by Perl.  The character was understood literally, but this may
+change in a future version of Perl.
 
 =item Unrecognized escape \\%c passed through in regex; marked by <-- HERE in m/%s/
 
 (W regexp) You used a backslash-character combination which is not
-recognized by Perl.  The character was understood literally.
+recognized by Perl.  The character was understood literally, but this may
+change in a future version of Perl.
 The <-- HERE shows in the regular expression about where the
 escape was discovered.