Any time you find yourself looking up a hash value for each key of a hash, don't forget the appropriately named each function.

while (my ($p9, $is_available) = each %is_available) {
    next if !$is_available;
    # do something with each available $p9
}

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The foreach (keys) iteration walks through the hash but averts its eyes from the values. The while (($key, $value) = each) iteration sensibly says we may as well grab the value while we're in the neighborhood.

In reply to Re: Foreach syntax - don't forget the each function! by Narveson
in thread Foreach syntax by JimSki

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