Question

I wish to assign a hash (returned by a method) into another hash, for a given key.

For e.g., a method returns a hash of this form:

hash1->{'a'} = 'a1';
hash1->{'b'} = 'b1';

Now, I wish to assign these hash values into another hash inside the calling method, to get something like:

hash2->{'1'}->{'a'} = 'a1';
hash2->{'1'}->{'b'} = 'b1';

Being new to perl, I’m not sure the best way to do this. But sounds trivial…

Answer 1

Your sub might be:

#!/usr/bin/env perl
use strict;
use warnings;

sub mystery
{
    my($hashref) = { a => 'a1', b => 'b1' };
    return $hashref;
}

my $hashref1 = mystery;
print "$hashref1->{a} and $hashref1->{b}\n";
my $hashref2 = { 1 => $hashref1 };
print "$hashref2->{1}->{a} and $hashref2->{1}->{b}\n";

One key point is that your notation for accessing the variables with the -> arrow operator is dealing with hash refs, not with plain hashes.