I was looking at the recipe of the day on Perl . Com and wondering how i would save the duplicate values when reversing a hash.

I was using the ternary syntax but it didnt work like I expected. Why does the second construct (without the braces) clobber the hash key with the value??? 

my %hash = ('apple2' => 'green',
            'apple1' => 'green',
            'banana' => 'yellow',
            'plum' => 'red');

my %distinct;
my %overflow;

while (my ($k, $v) = each %hash) {
# construct1
#   (defined $distinct{$v}) ? ($overflow{$k} = $v)
#                           : ($distinct{$v} = $k);
# construct2
   (exists $distinct{$v}) ? $overflow{$k} = $v
                          : $distinct{$v} = $k;
}
for (keys %overflow) {
   print "$_, $overflow{$_} \n";
}

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In reply to Recipe of day - hashes q. by agoth

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