What should the relation between \book / \bookpart be?

Simon Albrecht <[email protected]> writes:

>> What is wrong with a \bookpart?
>
> It causes a page break,

That is correct.  Maybe some way of being able to merge several
bookparts into one might make sense.

> and I understood your goal was to allow for the greatest possible
> flexibility in reusing segments of a project inside/outside of \book
> and \bookpart. That was me reading between the lines, which I felt to
> be necessary.

Well, the idea was to avoid roadblocks that are hard to understand.
"Why doesn't this work" should have an answer people can get behind.
I just have a bad imagination about "people".

>> If you want to think of things as mere text, you can use include, but
>> then they _are_ mere text without inherent structure, and depending on
>> the syntactic context they are included in, the structure may become
>> different or incoherent.
>>
>> There is a reason text-based macros are a nightmare.  You cannot use
>> them as black box.  You cannot rely on them being interpreted in a
>> particular manner.
>
> I don’t understand. Are you arguing against using \include to
> modularise a project? Of course using it always requires smart
> handling of what’s inside and outside any \includes.

That is the point.  You need to look inside of the includes.
"Modularisation" means somebody tells you "you can include this file and
it will do this and that" without needing to look inside.  And basically
being able to write

\bookpart { \include "someone else's LilyPond source file" }

without having to dig into what is in that file would be nice as an
ideal.  OF course it will not always work, but one can muse about just
what complications would make sense to people, and which will not
exactly be met with enthusiasm.

-- 
David Kastrup