Update to an update: Actually what I really wanted to do was:

$condition{$key} = \@{$query->param($key)} || $condition{$key} = $quer
+y->param($key);
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Why not use

$condition{$key} = [$query->param($key)];
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Which will give you an array-ref with 1 element when the parameter only has one value.

If you really need to, you can later do:

if (@{$condition{$key}} == 1) {
   # one value
}
else {
   # ... zero or more than one value
}
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