+If the key/value pair C<< hook => $hook >> comes first, C<$hook> will be called for each error with the object name as C<$_[0]>, the method name as C<$_[1]>, the current file as C<$_[2]> and the line number as C<$_[3]>.
+
+=item *
+
+Otherwise, a warning will be emitted for each indirect construct.
+
+=back
+
+=cut
+
+my $msg = sub {
+ "Indirect call of method \"$_[1]\" on object \"$_[0]\" at $_[2] line $_[3].\n"
+};