[] creates a new empty array and returns a reference to it.

If your goal was simply to empty the array, you could use @$array_ref = ();

If your goal was to free the array and the reference, you could use undef $array_ref; or let the reference fall out of scope.

{
   my $array_ref = [];
   for(1 ... 10) {
      my $hash_ref = { foo => foo, bar => bar };
      push(@{$array_ref}, $hash_ref);
   }
} # $array_ref is freed here.
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