perldelta for #17727

p4raw-id: //depot/perl@17745

diff --git a/pod/perldelta.pod b/pod/perldelta.pod
index 9ade819..8704322 100644 (file)
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -11,6 +11,17 @@ the 5.9.0 release.
 
 =head1 Core Enhancements
 
+=head2 Tied Arrays with Negative Array Indices
+
+Formerly, the indices passed to C<FETCH>, C<STORE>, C<EXISTS>, and
+C<DELETE> methods in tied array class were always non-negative.  If
+the actual argument was negative, Perl would call FETCHSIZE implicitly
+and add the result to the index before passing the result to the tied
+array method.  This behavior is now optional.  If the tied array class
+contains a package variable named C<$NEGATIVE_INDICES> which is set to
+a true value, negative values will be passed to C<FETCH>, C<STORE>,
+C<EXISTS>, and C<DELETE> unchanged.
+
 =head1 Modules and Pragmata
 
 =head1 Utility Changes