New DocBook support (0004)

[Pavel Sanda]

On Fri, Jul 03, 2020 at 04:07:20PM +0200, Thibaut Cuvelier wrote:
> On Thu, 2 Jul 2020 at 16:24, Pavel Sanda <sanda at lyx.org> wrote:
> > 1) OutputParams::DOCBOOK5 is used, but not defined.
> 
> Well, then it's there one commit in advance :)! Similarly, there's already
> a fontToDocBookTag function that is only used by commit #5.

Sure, I figured that out; the difference is that redudant fontToDocBookTag throws
innocent warning, while missing OutputParams::DOCBOOK5 breaks compilation
for everyone which which is no-go. So we either should better parcel
0004 vs 0005 or merge them.

> 2) lyx_2_4.py:
> >    You remove \outputformat docbook from header, but why?
> >    If someone had this as default output wouldn't he intend to use docbook5
> >    as default now?
> >
> 
> Is there any notion of "default output" in LyX?
> 
> Before, this parameter was used to enable DocBook support. This support is

Could be wrong but my reading was that's not enabling docbook, but setting docbook
as default output format.

> > 4) If someone used now removed tag Head/Element in
> >    Document->Settings->Local Layout
> >    will those be deleted in lyx2lyx conversion?
> >    (I dunno whether lyx2lyx calls layout2layout, please check)
> >
> > 5) If someone uses docbookattr/docbooktag in local layout and decides to
> >    export file from lyx 2.4 to lyx 2.3, shall/will those be removed?
> 
> 
> No, no conversion is performed (as indicated by José). It looks like this
> is an existing problem in LyX, though. If LyX complains when seeing unknown
> tags, they should get removed. I think it's just a warning in the console
> right now, so they might be kept in case the user gets back to 2.4.

I see, if it's true that we don't have layout2layout functionality used by lyx2lyx 
we can leave it as it is. Users using local layout within lyx file will be simply
left on their own.

Pavel