Hi there professsa,

In general, if you've got a reference to a hash - let's call it $ref - then you can work with it like this:

#construct a ref to an anonymous hash:
my $ref = {andy => 'likes cake'}; #note *curly* brackets
#another way
my %hash = (andy => 'likes beer too'); $ref = \%hash; #normal brackets
+ of course

#get at one specific value
print $ref->{andy};
#another way
print $$ref{andy};

#get all the keys
print keys %$ref;
#get all the values
print values %$ref;
#get key/value pairs
while (my ($key, $val) = each %$ref) {print "$key = $val"}

#copy the hash into a new hash
my %newhash = %$ref

#if you use the -> syntax with references to references, then you can 
+omit the ->s, after the first one, like this:
my $ref = { andy => {eats => 'cake'}};
print $ref->{andy}{eats}; #note only one -> necessary

[download]
More info can be found here: perlref or here: References quick reference (or, newly, here if you speak German: (lang: de) Referenzen) or by typing 'perldoc perlref' at your command line.

hth,
andy.

update: and the book "Effective Perl Programming" has an excellent explanation, very full, with pictures.

In reply to dereferencing syntax Re: Getting keys/values from a referenced hash by andye
in thread Getting keys/values from a referenced hash by professa

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