Page numbers in page_labels

[sciurius]

2.042 introduced a new method to specify page labels, page_labels, deprecating the old pageLabels method. Simultaneously the page number parameter changed from 0-based to 1-based. Even though documented, it can be easily overlooked, as I did, and, in my case it led to PDF documents that were not correctly dealt with by certain viewers.

Would it be possible to add a warning in page_labels when the page parameter is less than 1?

[ssimms]

Are you aware of anywhere in the spec that says page numbers can't be negative? 7.9.7 Number Trees only says "integers", and 7.7.2 Document Catalog only says that index 0 must be present.

If index -1 (i.e. page_labels(0) isn't allowed, I'll make it an error rather than a warning. If it's allowed, though, I worry that if the code throws a warning, someone's going to complain that they meant to do that. That said, it's probably still better to throw a warning in that case (along with asking the person why they're doing that) and remove it later...

[sciurius]

Even if the spec doesn't explicitly forbid negative numbers apparently there are PDF viewers that complain. A warning is much appreciated.