Warnings raised on getting value for undefined key

[dionys]

Call of $memd->get(undef, cb => sub { my ($val, $err) = @_; ... }) raises Use of uninitialized value within @_ in list assignment warning.

I'm not shure that it is an error. But…

The reason for this is that if $key is undef in _get() method then $args{cb}( $array ? \%res : $res{ $keys } ); calls with one undefined argument (not undef value).

So may be you wouldn't send request to the server if key isn't defined. Like this:

sub _get {
    my $self = shift;
    my $cmd  = shift;
    my $keys = shift;
    my %args = @_;

    unless (defined($keys)) {
        $_ and $_->begin() for $self->{cv}, $args{cv};
        $args{cb}(undef);
        $_ and $_->end() for $self->{cv}, $args{cv};
        return;
    }
    ...
}