Trie Folder

Folder.pm

package Folder;
use Moo;

has trie => (
    is => 'rw',
    isa => sub { die "$_[0] is not a Trie Obj!" unless ref $_[0] eq "Trie" },
    default => sub { Trie->new() }
);

sub read {
    my $self = shift;
    my $path = shift;

    my (undef, @path_arr) = split("/", $path);
    unshift @path_arr, ".";

    my $trie_ref = $self->trie;
    $trie_ref = $trie_ref->walk($_) for @path_arr;

    return $trie_ref->version();
}

sub write {
    my $self = shift;
    my ($path, $num) = @_;

    my (undef, @path_arr) = split("/", $path);
    unshift @path_arr, ".";

    my $trie_ref = $self->trie;
    $trie_ref = $trie_ref->walk($_) for @path_arr;

    return $trie_ref->inc($num || 1);
}

1;

package Trie;
use Moo;

has data => (is => 'rw', default => sub { +{ "." => {"/b" => 0} } });

sub walk {
    my $self = shift;
    my $c = shift;

    my $previous = $self->data->{"/v"} || 0;
    $self->{data}{$c} ||= { "/b" => 0 };
    $self->{data}{$c}{"/v"} = $self->{data}{$c}{"/b"} + $previous;

    return Trie->new(data => $self->{data}{$c});
}

sub version { shift->data->{"/v"} }

sub inc { $_[0]->data->{"/b"} += $_[1] }

1;