How to access hash from object - perl

Question

I have written a small class which just got some getter and setter methods. One of those Properties is a hash.
sub getMyData
{
my $objekt = shift;
return $objekt->{MYDATA};
}
sub setMyData
{
my $objekt = shift;
my %myData= shift;
$objekt->{MYDATA} = \%myData;
}
If i set the value like this in another skript which access my class:
my %test;
$test{'apple'}='red';
$objekt = MYNAMESPACE::MYCLASS->new;
$objekt->setMyData(%test);
I thought i can access this value easy via:
my $data = $objekt->getMyData;
print $data{'apple'};
I just get undef value.
Output from Dumper:
Can someone tell me what's wrong here and how i can access getMyData and print the value 'red'?

Answer 1

shift removes and returns the first element of an array. Inside of a subroutine a bare shift operates on #_, which contains a copy of all arguments passed to that subroutine.
What is really happening here is that setMyData is being passed this data:
setMyData($objekt, 'apple', 'red');
The first shift in setMyData removes $objekt from #_
The second shift in setMyData removes 'apple', but since you assign the result of this shift to a Hash it creates a Hash that looks like this: 'apple' => undef
You take a reference to this Hash and store it in the MYDATA key of $objekt
What you really want is to assign the remainder of #_ to your Hash:
sub setMyData {
my $objekt = shift;
my %myData = #_;
# my ($objekt, %myData) = #_; (alternative)
$objekt->{MYDATA} = \%myData;
}
Another option is to instead send a Hash reference to setMyData, which would work with shift:
sub setMyData {
my $objekt = shift;
my $myData_ref = shift
$objekt->{MYDATA} = $myData_ref;
}
$objekt->setMyData(\%test);

Answer 2

You are missing the dereference arrow. Because you put a hashref (\%myData) in, you also get a reference out.
my $data = $objekt->getMyData;
print $data->{'apple'};
# ^
# here
You also need to change the assignment, because you are passing a list to the setter, not a reference. shift is for scalar (single) values, but %test gets turned into a list (many values).
sub setMyData
{
my $objekt = shift;
my %myData = #_;
$objekt->{MYDATA} = \%myData;
}
However, there are a few more issues with your code.