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[WebAim] Whither /TOC and /TOCI in PDF 2.0? PDF accessibility question.


From: Rick Davies
Date: May 14, 2019 11:38AM

Hello Everyone,

This is a question about accessibility and the PDF 2.0 standard.

The PDF 2.0 standard, ISO 32000-2:2017(E), says that /TOC and /TOCI, and several
other standard structure elements, are no longer 'defined'. (Annex M, page 958.)

OTOH there are many US Goverment agency documents containing accessibility
guidelines saying, e.g., entries in tables of contents *must* be tagged /TOCI.
(Table of contents entries in the PDF version of ISO 32000-2:2017(E) are tagged
/TOCI. That's presumably because it's a PDF 1.7 document.)

The complete list of previously-defined standard structure elements, *undefined*
by PDF 2.0, is: Sect, Art, BlockQuote, TOC, TOCI, Index, NonStruct, Private, Quote,
Note, Reference, BibEntry, Code.

Does anyone know why these standard structure elements were 'undefined' in PDF 2.0?
What is the significance of their removal/undefining/defenestration in PDF 2.0?
And what should be used instead?

If the PDF version of ISO 32000-2:2017(E) PDF 2.0 standard were to be in Version 2.0
PDF instead of version 1.7 PDF, would the table the table of contents entries still
be tagged /TOCI, or tagged some other way?

The answers must be obvious, but I can't find 'em. If anyone has time to explain
this, it would be wonderful, especially if the explanation could be made at a
level suitable for someone who finds understanding the various ISO PDF standards
woefully difficult.

Or maybe PDF 2.0 is ignoreable for, say, the next ten years in terms of accessibility,
& most other things??

Thanks very much ...