It looks like deleting the last element of an array no longer deletes the undefined elements before it:
> my $foo = [0,1,2,3,4]; say $foo.elems; say $foo.perl 5 [0, 1, 2, 3, 4] > $foo[4] = Any; $foo[3] = Any; say $foo.elems; say $foo.perl 5 [0, 1, 2, Any, Any] > $foo[4] :delete; say $foo.elems; say $foo.perl 4 [0, 1, 2, Any] The same with class Foo: > class Foo {}; my $foo = [0,1,2,3,4]; $foo[4] = Foo; $foo[3] = Foo; $foo[4] > :delete; say $foo.elems; say $foo.perl 4 [0, 1, 2, Foo] Is that the expected behaviour? The IRC log above expressed same doubts about that.