cloning closures everywhere works

$ cat church

# church 0 = \f -> \x -> x

multi church(0) {
    pir::clone(-> &f { pir::clone(-> $x { $x }) });
}

# church n = \f -> \x -> f (church (n-1) f x)

multi church($n) {
    pir::clone(-> &f { pir::clone(-> $x { &f(church($n - 1)(&f)($x)); }) });
}

# unchurch n = n (\x -> x + 1) 0

sub unchurch(&c) {
    &c(pir::clone(-> $x { $x + 1 }))(0);
}

# plus m n = \f -> \x -> m f (n f x)

multi plus(&m, &n) {
    pir::clone(-> &f { pir::clone(-> $x { &m(&f)(&n(&f)($x)) })})
}

say unchurch(plus(church(2), church(3)));

$ perl6 church 
5