I am writing a subroutine that chooses a random key from a hash, but the choice is weighted depending on the value of the hash. The keys are a list of words from a text, the values are the frequency of occurence. (This is from the online book "Learning Perl the Hard Way" http://greenteapress.com/perl/)

anyway I don't understand the syntax error being flagged: 

# sub weighted_hash
# chooses and returns a random key from a hash;
# the probability of choosing a specific key
# is weighted by the value associated with that key
sub weighted_hash{
   my $hashref = shift;
   my %hash = $$hashref;
   my @weighted;

   foreach my $key (keys %hash){
      my $weight = $hash{$key};
      while ($weight >0){
         push @weighted $key;
         $weight--;
      }
   }
   rand_elt @weighted;
}

[download]
update: changed
push @weighted $hash{$key);
to
push @weighted $key;error still there

In reply to "Scalar found where operator expected", references by jjohhn

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