trying to implement multidimensional slicing

gistfile1.txt

class Foo is Array {
    multi method postcircumfix:<[ ]>(\SELF: LoL $coords) is rw {
        my $subcoords = $coords[1..^*].lol;
        if +@$subcoords == 1 {
            $subcoords = $subcoords[0].list;
        }
        for $coords[0].list {
            SELF[$_][@$subcoords];
        }
    }
}

my $farr = Foo.new();

for (0..7) X (0..7) -> $x, $y { $farr[$x][$y] = $x ~ $y }

say $farr[1, 2; 3, 4].perl;
say $farr[0, 1; 1, 4].perl;
$farr[1, 2; 5, 6] = <foo bar>, <baz quux>;
say $farr;