Velato VS abjad

Hi, I'm the creator of Velato. I will be reworking the website to include more examples later this year. In the mean time, the latest version of the compiler is on github: https://github.com/rottytooth/Velato

No one has yet written a quine although I would love to see one -- perhaps outputting its representation in lilypond format.

In 2009, I made Velato, an esolang where code is written in pitch values (https://github.com/rottytooth/Velato) encoded as MIDI files. So sort of the opposite of writing algorithmic music (where the human programmer writes music to satisfy conditions of the program). Before switching to LilyPond, I'd used GUIDO with a GUIDO-to-MIDI generator, but it was always awkward. Part of the challenge is that notes can be sounded simultaneously to make the score work better musically, but still need to appear in the correct sequence in the MIDI file for the program to succeed; something that LilyPond handles correctly. There's a transparency to how LilyPond functions that is not always there with programs that try to be "helpful" and clean-up or rearrange information.

And for the intrepid folks who prefer algorithmic or computer-assisted composition, there's Abjad, a Python-based wrapper around LilyPond.

https://abjad.github.io/

The abjad library looks really interesting, as it basically gives a Python API for Lilypond. It would help me do all the main features I want. However, from the way it does its Lilypond objects, each song would have to output its own PDF. I don't see how I can use something like PyLaTeX to concatenate all those existing PDFs and make nice hyperlinks and indexes for it all.

This could be done in many other ways. Indeed this is not even the standard way (that would be coding a 2to3 fixer). The practical solution is not general (for instance, it does not support nested classes). Also, it has problems with comments (as we lose them in the AST). But, for the practical purpose (patching abjad) it was good enough (You can see the result here.