INS, DEL and MOD: Markup for Denoting Changes/Revisions

related resource: Modification Markup Use Cases & Requirements

1. there is a need for a tertiary semantic marker to compliment and plug a hole left by INS and DEL:

• use INS - to indicate inserted text
• use DEL - to indicate deleted text
• use MOD - to indicate modified text

2. why are INS and DEL insufficient?

• they are indicators of text that has been deleted from or introduced to a document instance, but they are incapable of communicating that text has been modified;
• there is not a binary relationship between text in a document; XHTML2 semantics should capture the concept of text which has been modified, but neither inserted (new text) or deleted (text removed from the document)

3. in most DIFF documents, the generic SPAN element is used to color-code text that has been inserted, deleted, or modified; this, of course, is a violation of WCAG (the Web Content Accessibility Guidelines) and is in direct opposition to the separation of presentation from structure; such documents (and the scripts which generate them) should be marked up using INS, DEL or MOD -- whichever most accurately reflects the status of the text.

4. any exploration of this subject would be incomplete without considering if multiple elements for the purposes for which INS and DEL were defined are necessary?

• why not have a single element (such as MOD or CHANGE) with the following type or role values?
  • ins (inserted text)
  • del (deleted text)
  • mod (modified text)