@array2 will be empty if there are no matches. A way to test this condition is:

if (@array2) {
   # array2 is not empty
} else {
   # array2 is empty
}
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Used in this way, @array2 returns its size. So, you can write tests like this:

if (@array2 > 3) {
  # array2 has more than three elements
}
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The first test is short-hand for if (@array2 != 0) { ....