> On 17 Mar 2025, at 11:01, Aura Kelloniemi <kaura....@sange.fi> wrote: > > I am developing a tool for processing musical notation in Haskell. I want to > be able to import LilyPond scores and as I don't want to parse LilyPond's > surface syntax and write a Scheme interpreter, I have decided to export > LilyPond scores as S-expressions (which are easy to generate in Guile). > > The process works such that my import routine invokes LilyPond with a custom > init file, which runs the S-expression export routine. > > The command that my importer uses is: > $ lilypond --init /absolute/path/to/init-file.ly > relative/path/to/score-file.ly > > The exporter writes output to stdout. > > I have a few questions/problems: > > 1) First of all, is this a good strategy at all or would there be a better way > to make LilyPond run a custom export code and prevent it from generating any > output files itself? I would like my solution to be forwards-compatible from > LilyPond 2.24 onwards to some extent at least..
In my experience, it is hard to work with source code directly, because of the difficulty to pin down dependencies. GHC has a FFI interface for C++, and Guile has a C interface, so it might work to call it directly from the Haskell code. What is missing is a direct LilyPond C++ interface. https://wiki.haskell.org/GHC/Using_the_FFI
