Nesting Hashes in Perl.

faref · 06-07-2006, 01:59 PM

I've been staring at this all day and it's given me a bit of a headache.

(This is perl not php, but I like the colors

)

PHP Code:



@MasterList = ("Hardware","Hardware Overview","Serial Number", "123456789"); 
%HashMasterList ={@MasterList[0] => {@MasterList[1] => {@MasterList[2] => @MasterList[3]}}}; 
print "The Serial is: $HashMasterList{'Hardware'}->{'Hardware Overview'}->{'Serial Number'}\n";

Why does this not print "The Serial is: 123456789"? I've googled but there does not seem to be much in the way of nesting hashes...especially three deep based off of names stored in an array. Any help would be most appreciated.

demon_vox · 06-07-2006, 03:00 PM

Hi,
I've modificated two things and it worked.
The first one is when you write @MasterList[0]. Remember that you want to access a particular element, and that is a scalar value. So you should put a $ instead of a @ (and with all the @MasterList[ ] of the second asignment).
The second one is that I define the HashMasterList with parentesis instead of brackets. I believe, but I am not sure (and I am a little out of time to check it out), that if you use brackets you are defining a reference to an hash as contrary of direct hash, which would change the syntax from where you are reading an element.

So, that line would end up like this:

Code:

%HashMasterList = ($MasterList[0] => {$MasterList[1] => {$MasterList[2] => $MasterList[3]}});

Hope this is useful

faref · 06-07-2006, 05:03 PM

wow.

This is only my third day of perl and you've been most helpful, thanks!