I am a little uncertain as to what you mean when you say that the array is empty, because your pseudo code says

all the elements of @array contains &nbsp

So, if you want to test if any of your array elements have somthing other than blank characters, you would need something different.

if (! @array) {
  # there are NO elements, do what you need to do
}
elsif (grep ! /^\s*$/, @array) {
  # there are elements in your array, and at least one
  # of them contains a string that has something other
  # than spaces
}
else {
  # there are elements in your array, but they are either
  # empty strings, or strings with spaces
}
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