Initialize hashes of arbitrary depth

hash.pl

my %h;

my @keys = <a b c d e>;
my $value = 'foo';

fill %h, @keys, $value;
say %h.perl;

sub fill(%hash is rw, @keys, $value) {
    my %h := %hash;
    my @k = @keys;
    my $last_key = @k.pop;
    for @k -> $k {
        %h{$k} //= {};
        %h := %h{$k}
    }
    %h{$last_key} = $value;
}