RE: Chapter 3 of "LilyPond Extending" document

[Peter Gentry]

You are spot on David. I spend a lot of time transposing music for a small band of amateur wind players.  I use the said snippet as an include file "enharmonic.ly" to tidy up the accidentals. My issue is that the tidy up takes no account of the current key signature and so sometimes you are left with a Gb say when there is F# in the key signature. I am trying to get at the list of sharps and flats from the keysignature interface use to force the Gb to F# (and adjust any other unpleasant accidentals).

 

I can see that there is such data lurking about but so far I haven't been able to extract it.  This has lead me into a crash course of C++ and Scheme which at 73 is proving interesting but time consuming - (I was brought up on Basic and Fortran)

---

From: David Nalesnik [mailto:address@hidden
Sent: Thursday, November 27, 2014 3:17 PM
To: Peter Gentry
Cc: lilypond-user
Subject: Re: Chapter 3 of "LilyPond Extending" document

On Thu, Nov 27, 2014 at 6:34 AM, Peter Gentry <address@hidden> wrote:

This chapter headed "LilyPond Scheme Interfaces" would be most useful to the tyro since it would help to get information into and
out of music streams.

However it is missing from the 2.18.2 documentation which relates to the 2.16.2 release.

Inside the 2.18.2 source download there is a file scheme-tutorial.itely which refers to the 2.17.11 unstable version. This is
somewhat different from the above but still has no chapter "LilyPond Scheme Interfaces"

Is there an intention to provide this chapter or is it a low priority for the experts?

 I think it would be very useful, I don't know of anybody actively working on it.  Speaking as somebody who could contribute to this section, I wouldn't know where to begin!

One issue here is that there is much to work on in LilyPond and a rather small pool of contributors.

Still battling on to fathom a way to recover key signature details for mods to enharmonic.ly - currently pondering
key-signature-interface.cc

As far as I can tell, enharmonic.ly is not a file in the distribution--where are you getting this?  From other threads of yours which include the code, it seems you are referring to the snippet  http://lilypond.org/doc/v2.18/Documentation/snippets/pitches#pitches-transposing-pitches-with-minimum-accidentals-_0028_0022smart_0022-transpose_0029

As far as your quandary, what are you trying to do?  Maybe I or someone else can provide some insight.

Best,

David