interactive Lilypond

[Guido Amoruso]

Hi!

While fiddling with Lilypond's internals, I often like to play
interactively with data structures: so I've made a script like this

  #!/bin/bash
  lilypond -e "(use-modules (ice-9 readline))
               (activate-readline)  
               (top-repl)"

which gives me an almost initialized Lilypond environment; then I write
at the Guile prompt 

  (ly:parse-file (ly:find-file "declarations-init.ly"))

to complete the bootstrap and be able to play with music expressions,
produce pdf output interactively, search for existing Lilypond functions
thanks to Readline autocompletion, and so on...

This is very nice, but I'd like to have even a better environment with
regard to these aspects:

1. Initialization. I'd like to start the fully initialized environment: 
   I've tryed to run

     "lilypond -e (ly:parse-file (ly:find-file "declarations-init.ly"))
                  (use-modules (ice-9 readline)) (activate-readline)
                  (top-repl)"

   but the parsing happens in a different module, so I don't get the 
   symbols imported in the environment. Is there a workaround? 

2. Creation of music expression. I'd like to be able to do something 
   like

     "(define music (parse-string "{c'' dd'}")"

   in order to build scores both interactively and programmatically. I 
   know there is "ly:parse-string", but I don't understand how it 
   should work. This would be sure interesting in non interactive
   use cases, too.


By the way, is there an IRC channel for Lilypond developers? Would you
guys find it useful?

Cheers,
Guido Amoruso