return wantarray ? %$extra : $extra;
}
+# ----------------------------------------------------------------------
+sub remove_extra {
+
+=head2 remove_extra
+
+L</extra> can only be used to get or set "extra" attributes but not to
+remove some. Call with no args to remove all extra attributes that
+have been set before. Call with a list of key names to remove
+certain extra attributes only.
+
+ # remove all extra attributes
+ $field->remove_extra();
+
+ # remove timezone and locale attributes only
+ $field->remove_extra(qw/timezone locale/);
+
+=cut
+
+ my ( $self, @keys ) = @_;
+ unless (@keys) {
+ $self->{'extra'} = {};
+ }
+ else {
+ delete $self->{'extra'}{$_} for @keys;
+ }
+}
# ----------------------------------------------------------------------
sub equals {