Select Code to Download

%functions = (
  '?' => 0,
...
);
# have to initialize this outside declaration of %functions
$functions{'?'} = $functions{'HELP'};

while(<>) {
  $func = $_;
...
    print "\"$func\" not defined\n";
  }
}

    &$functions{$func};

    my $code;
    $code = $functions{$func};
    &$code;