I'm deliberately conflating linear layout of code with the flow of the program, because that's what makes it easier to read. Exit points other than } are typically easier to notice, and can conceptually link "special thing happens here that I should watch for" with that point in a programmer's head.

I want a warning at the } if you have created an object that is going to do something special at that point and nothing has been done to make it visible. Call your destructor explicitly as a reminder, unless doing so would be even worse (i.e. you built a dozen of these objects in the same scope), in which case, put a single-line comment at the } and another at the line that turns off the warnings.

But as I said before, this is a stylistic thing, and I imagine it's not really worth getting into a big scuffle over it.

Exit points other than } are typically easier to notice, can conceptually link "special thing happens here that I should watch for" with that point in a programmer's head.

No. How many exit points are in this code:

sub foo {
  my $resourceHandle = acquire_locked_resource();
  my $dbh = get_database_handle;
  my $count = get_current_users($dbh);
  my $elapsed = get_elapsed_time();

  my $users_per_second = $count/$elapsed;

  $resourceHandle->output("$users_per_second users/s");

  $resourceHandle->release;
};
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Assuming that you haven't deliberately made things worse on yourself by concealing objects, a programmer new to your code will note that you have kindly warned him that $resourceHandle is an object via the ->release just before the closing brace (this is the thing that I want the warning to check for, and you've done exactly that), and check acquire_locked_resource, get_database_handle, get_current_users, get_elapsed_time, and the output method on whatever acquire_locked_resource claims in the comments to return, and assume that you were sane enough to make the release an explicit destructor before the brace. If you did something insane like sticking an object in $count and $elapsed and hid an operator overload in '/', or hid an object in $users_per_second and then tinkered with the lvalue assignment, then committed that sub without comment, you deserve to have your access revoked.

In my stylistic opinion, of course. No personal offense or disrespect intended, especially given that this is just example code.

That said, the original topic at hand is warning messages on unused variables, and you've declared: $resourceHandle, $dbh, $count, $elapsed, and $users_per_second, and every single one of those got used. Why are you worrying about the warning on this code?

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