Although I'd recommend using further arrows other wise you'll get your knickers in a twist.

Remember that % means a whole hash, and $ is a hash value (as it is in effect a scalar).

So if $hashref contained a hash, then you could access the whole hash with %$hashref (the hash % in the scalar reference $hashref).

Remember references (or pointers if you will) are a single value (a single reference), so effectively a scalar, hence the $.

Use arrow notation and the appropriate brackets to access the nested hash/array you need. 
$hashref = \%hash; # $hashref is a scalar pointing to %hash
%$hashref   or   %{$hashref}# the same as %hash

$hash{'key'}
# is the same as
$hashref->{'key'}

$hashref->{'key'} = \@array; # Make this key a reference to the array 
+@array
@{$hashref->{'key'}} # the same as @array, the extra brackets {} show 
+you are looking for the array in $hashref->{'key'} and not an array i
+n $hashref

$hashref->{'key'}->[0] # same as $array[0]

[download]
It takes a little getting used to, but all makes sense after a while.
The books Advanced Perl Programming (First Edition) and Intermediate Perl cover this quite well


Lyle

In reply to Re^2: Brief Hash Tutorial by cosmicperl
in thread Brief Hash Tutorial by gw1500se

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