Re: Where to put new Scheme engravers?

[Trevor Daniels]

Urs, you wrote Sunday, September 28, 2014 10:38 AM


> Am 28.09.2014 11:36, schrieb Trevor Daniels:
>>
>> Most of the engravers are written in C++ and each is a separate
>> file in the lily/ directory.  There's a little above engravers here:
>>
>> http://www.lilypond.org/doc/v2.19/Documentation/contributor/engraver-tutorial
> 
> Yes, I've seen that, and as you say this only gives information about 
> C++ engravers.
> 
> But I do have an engraver written in Scheme (not by me) that I find very 
> useful. I could make it available in openlilylib, but I think it's a 
> very common notation that should be available in LilyPond itself 
> (printing double barlines before time signature changes).
> 
> Do you want to say that it's inappropriate to add Scheme engravers to 
> LilyPond and that it should be rewritten in C++ for that (which I couldn't?

Ah, sorry, I missed the keyword "Scheme" in your original post.

Currently there is just one Scheme engraver in the LilyPond codebase.
It is in scm/scheme-engravers.scm, and was added as part of issue 2445.
You may find it useful to read through that issue:

https://code.google.com/p/lilypond/issues/detail?id=2445

It would be sensible to add your engraver to to same file.  Later, if
many more Scheme engravers appear, it might be better to separate
them out into individual files.  And by then the documentation problem
mentioned by David might have been fixed.

Trevor