Populate a select list with integers

Hello,

I've just started getting going with Drupal 7.

I'm trying to add a weight value to an image. I've created an integer field - widget type Select list and I want to populate the select list. In Drupal 6 (using CCK) it was really easy to use a bit of php like so:

$value = -100;
for( $i = 0; $i <=200; $i++ ) {
$values[$i] = $value++;
}
return $values;

This would populate the select list with integers from -100 to 100. Easy.

Drupal 7 doesn't seem to have this option and seems to expect me to manually add a list of numbers like a non-programmer would have to. Is that so? Please tell me I've just overlooked something.

Any help would be appreaciated.