How do I prevent List::MoreUtils from warning about using $a and $b only once?

Question

The List::MoreUtils module indicates that you use the variables $a and $b when supplying the BLOCK that goes with the pairwise

Answer 1

This is probably a bug in List::Util.

Turning off warnings globally is probably not a good idea, however you could do something like this:

{
  no warnings 'once';
  return join("_", @monsters) if @monsters && List::Util::reduce { $a && $b // 0 > 0 } 1,@monsters;
}

This would turn off the relevant warning category for that part of the code only.