Good question. Hashes are a source of vague confusion to many programmers (some of whom I've worked with, particularly C++ programmers, treat them with rather a reverence bordering on mysticism).

First, rearrange your lines to put the chomp BEFORE any code that references $_. This way the value returned from split(), which is being assigned to $value won't end in a newline ("\n").

Then, assign the VALUE (in $value) to the hash indexed by $key. Your code associates $key with itself, not with $value.

Also, note that split /;/; is IDENTICAL to what you have, split(/;/, $_); but is more succinct (once you're accustomed to Perl idioms).

while (<OUTFILE>) {
    chomp;                              # <== move the chomp here
    my ($key, $value) = split /;/;
    $calhash{$key} = $value;            # not '= $key'
}
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That addresses the hash loading issues.

Your printing code is fine, except that you are printing each value ($calhash{$key}) with a blank (see my $value = ""; at the top of your code), not each key and its associated value, as you clearly mean to do:

foreach my $key (sort {$b cmp $a} keys %calhash) {
    my $value = $calhash{$key};
    print TESTFILE "$key;$value\n";
}
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Update: Apologies to all and sundry who beat me to the punch here. When I started, there were no replies!

dmm

If you GIVE a man a fish you feed him for a day
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