File Coverage

blib/lib/Data/StackedMap.pm

Criterion	Covered	Total	%
statement	51	51	100.0
branch	8	8	100.0
condition			n/a
subroutine	15	15	100.0
pod	10	10	100.0
total	84	84	100.0

package Data::StackedMap;

use 5.00503;
use strict;

use vars qw($VERSION);

$VERSION = '0.03';

use strict;

use Carp qw(croak);

sub new {
    my ($pkg, $default) = @_;

    my $self = bless [ {} ], $pkg;

    if (ref $default eq 'HASH') {
        %{$self->[-1]} = %$default;
    }

    return $self;
}

sub delete {
    my ($self, $key) = @_;

    return delete $self->[-1]->{$key};
}

sub exists {
    my ($self, $key) = @_;

    for my $layer (1..@$self) {
        return -$layer if exists $self->[-$layer]->{$key};
    }

    return 0;
}

sub get {
    my ($self, $key) = @_;

    my $layer = $self->exists($key);
    return $self->[$layer]->{$key} if $layer;

    return;
}

sub keys {
    my $self = shift;

    my %keys;
    for my $layer (1..@$self) {
        my @kkeys = CORE::keys %{$self->[-$layer]};
        @keys{@kkeys} = (1) x scalar @kkeys;
    }
    return CORE::keys %keys;
}

sub top_keys {
    my $self = shift;

    return CORE::keys %{$self->[1]};
}

sub pop {
    my $self = shift;

    if (@$self == 1) {
        croak "Can't pop single layer stack";
    }

    return pop @$self;
}

sub push {
    my $self = shift;
    push @$self, {};
}

sub set {
    my ($self, $key, $value) = @_;

    $self->[-1]->{$key} = $value;
}
*put = \&set;

sub size {
    my $self = shift;
    return scalar @$self;
}

1;
__END__