RE: Pointers

From: Paul Kraus (pkraus_at_pelsupply.com)
Date: 11/20/03 

To: "'Eric Walker'" <ewalker@micron.com>
Date: Thu, 20 Nov 2003 14:23:43 -0500

Forget about references for a minute.

%hash <- refers to the entire hash.

$hash{key} refers to one element of that hash.

So as a reference you would address the entire hash as %$hashref
Or a single element of that hash as $$hashref{key}

HTH
Paul

-----Original Message-----
From: Eric Walker [mailto:ewalker@micron.com]
Sent: Thursday, November 20, 2003 2:20 PM
To: Paul Kraus
Cc: 'perlgroup'
Subject: RE: Pointers

ok why the $$ instead of the %$?

sorry confused.

On Thu, 2003-11-20 at 12:08, Paul Kraus wrote:

    $$overdate{key}
    
    Perldoc perlref
    
    -----Original Message-----
    From: Eric Walker [mailto:ewalker@micron.com]
    Sent: Thursday, November 20, 2003 2:03 PM
    To: perlgroup
    Subject: Pointers
    
    
    Hello all, newbie here got a few questions:
    I am working with pointers and I sort of understand them and then I
    don't. I understand that instead of making a variable for a
particular
    value you can use a pointer to access the same data. So the new
    variable stores the pointer to the old data. ie.... $a = "mom";
          $b = \$b;
    print $$b --> mom
    
    Ok so what I don't understand is when do I need to dereference the
    pointer for hashes. so I have a hash pointer.. \%overData. Now
how do
    I access this hash. %$overData?
    
    Thanks
    confused.
    newbie
    
    
    
    

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