Dear Monks, everyday at the Monastery is a new day for me that I enjoy since it accompanies practice for my Perl learning experience. I have learnt a lot ever since I joined and today I am learning complex data structures incited by my reply in this interaction to this node. I found myself hitting a roadblock so I wanted to learn Perl advanced data structures in a systematic way to be able to answer such questions myself.

My question here spans Perl references to hashes or arrays stored in an anonymous hash, I solicit an explanation to decloud my confusion of why there is no difference in dereferencing a reference to a hash or array using ${} block in the following example and dereferencing the same with only the infix arrow operator. With "no difference" I mean I don't get an error when strictures are on.

Here is the example:

%hash = (fruit=>'apple', veggie=>'corn');
@array = qw(1 2 3 4 5);
$struct={
        hashRef => \%hash,
        arrayRef => \@array
        };
print ${$struct->{hashRef}}{fruit},"\n";     #using the ${}
print ${$struct->{arrayRef}}[0],"\n";

print $struct->{hashRef}{fruit},"\n";  #can this be better to use?
print $struct->{arrayRef}[0],"\n";

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In reply to Referencing in advanced data structures by biohisham

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