allow nested facsimile elements

[martinascholger]

This PR addresses #2565

[martindholmes]

After some discussion with @martinascholger, we decided that this approach is too loose, and allows lots of weird content mixes (facsimiles interleaved with surfaces, for instance) whose meaning is hard to fathom. The feature request is just for the ability to create a facsimile containing child facsimiles, so perhaps the content model should just be an alternate between the existing content model and one or more facsimiles.

[tuurma]

@martinascholger @martindholmes I agree with the proposed alternate - either nested facsimiles or surfaces etc

[sydb]

Just to be sure I understand, y’all are proposing

facsimile = ( model.graphicLike | surfaceGrp | surface )+ | facsimile+

as opposed to the current definition (on this ms_2565_facsimile branch) of

facsimile = ( model.graphicLike | surfaceGrp | surface | facsimile )+

Right? If that’s the case, seems like a good idea to me, but I would want to hear from the likes of @MatijaOgrin, @jamescummings, or @schassan before merging into dev.

[sydb]

(Just to be clear, the actual content model being discussed allows an optional <front> before, and an optional <back> after, all the other stuff. Thus what I really should have said above is that the intervention suggestion is to use

facsimile = ( front?, ( model.graphicLike | surfaceGrp | surface )+, back? ) | facsimile+

instead of

facsimile = front?, ( model.graphicLike | surfaceGrp | surface | facsimile )+, back?

which I still think is a good idea.) Given that we have gotten a thumbs-up from @martinascholger, @martindholmes, @tuurma, myself, and @MatijaOgrin,¹ I am inclined to just make the change and then ask @jamescummings for a final review.

Although I do wonder if there is any need for discussion or examples in the Guidelines.

Note
¹ Presuming the thumbs-up emoji was approval of the idea, not just approval of getting feedback, first.

[martindholmes]

Looks good to me. I agree that an example tying this to the parallel with msPart would be helpfull.

[sydb]

Egads! @martindholmes, my apologies! You just reviewed it without my having pushed the latest change. Pushed now, which is a bit premature, as we know it will fail to build until #2680 is merged (presumably into dev and then to this branch).