in reply to The Drivel is in the Details

$source is a reference to a hash. You find the keys by de-referencing it (%$source) then you dereference it with the arrow in $source->{node}. You could use the format you are used to if you do something like: 
my %newSource = %$source; # dereference it all at once
foreach my $node(keys (%newSource)) { # note no %$
   #...
   $newSource{$node}; # already dereferenced.

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update I'm not recommending that you change the code, but showing a similar situation to explain the code. If you are thinking of changing the code, see the important caveat mentioned by Random_Walk.

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Re^2: The Drivel is in the Details
by Anonymous Monk on May 29, 2007 at 22:28 UTC
    Thank you - I think I can explain it from there.

    Peace
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Re^2: The Drivel is in the Details
by Random_Walk (Prior) on May 30, 2007 at 22:48 UTC

    I think you should point out that when you do 

    
my %newSource = %$source; # dereference it all at once

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    you are not just dereferencing $source but making a new and independent copy in %newSource. This may have implications if the code evolves. Any change made to one array will not be reflected in the other, for instance an element removed from %$source is not removed from %newSource and the removal of $source will not imply removal of %newSource

    Cheers,
    R.

    Pereant, qui ante nos nostra dixerunt!
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