I'm new to Perl and am having a hard time working with hashes.

I have hash from a module successfully being passed into a function in another module as @_. I can Data::Dumper it to the screen. I thought I had success by simply being able to get the hash into my function. However, I can't figure out what to do next.

If I say:

sub test_parser(\%) {
use Data::Dumper;
print Dumper(@_);
}

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...the hash prints to the screen fine. But now I need to access the hash. It's a hash of hashes. So I figured I'd do something like this:

%mytest = @_

...so I could then work with at as a hash inside my function. But this does not work.

How can I pass a hash into a function and then get it back into a hash, or a reference or whatever, that I can work with?

I need to get @_ into a form like %myhash, so I can run foreach something like this:

    %myhash = @_; #this is where the problem is!!
    
    foreach $key (keys %myhash) {

        %subhash = %{$myhash{$key}};
        
        foreach $subkeys (keys %subhash){

            $subkey_val = $subhash{$subkeys};
            
            #print "$subkeys and $subkey_val\n";
            
            if ($subkeys eq "competitor_firm" && $subkey_val eq ""){
                
                delete $competitors_only{$key};
            
            }

        }

    }

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What's inside the above hash isn't so important. The main thing is that I need %myhash to be assigned the value of the hash that's inside @_. I have this routine running elsewhere in a module where I successfully duplicated a hash I needed to delete some values from. In case where I have the above routine working fine, I have this:

%myhash = %myoriginalhash;

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SUMMARY: How do I take a hash being passed into a function as @_ and convert it to a hash I can do something with, like %myhash?

Thanks

Doug

In reply to Trouble passing hash into function by dbonneville

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