hmm could be, I was thinking of the operator not of the iterator, but when using reverse one should get a list like before and it doesn't help either:

use bigint;
my $answer = 1;
print ref $answer;    # prints "Math::BigInt"
 
for my $i (1..1) {
  print ref $i;       # prints nothing
}
for my $i (reverse 1..2) {
  print ref $i;       # prints nothing
}
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Lets be honest, these kind of problems are one of the reasons why Python is more popular for scientific calculations.