All of which makes me think that it's not really worth while pursuing this development any further. As an ex-programmer (yes, I sometimes did write comments, but in assembler you rather have to) it's just a bit frustrating not to be able to work it out by myself.
What you and Jeffery have cooked up is more than adequate for my immediate needs. For which many thanks again.
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Tuesday, February 28, 2017, 6:32:53 PM, you wrote:
> On Tue, Feb 28, 2017 at 12:02 PM, Simon Albrecht <address@hidden> wrote:
>> Am 28.02.2017 um 12:56 schrieb Peter Toye:
>> I'm trying to get my head around the code you sent me - it seems that real
>> programmers (you and David both) don't write comments :)
>> I figure that’s more a question of whether they have time and motivation to
>> do so.
>> Best practice would probably be writing enough comments that someone who is
>> reasonably familiar with the language and context should understand it at
>> first reading.
> Well, time is an issue. Also an issue is the feeling that a good
> solution requires functionality which isn't (so far as I know) part of
> LilyPond. (It would be nice to be able to get info about the unfolded
> music when it's folded -- i.e., the bar numbers Peter is after.) And
> that I shouldn't be coopting the MeasureCounter grob.
> Also relevant is the fact that this code requires a lot of familiarity
> with LilyPond internals. Certainly a comment here and there is
> useful, and I'm remiss, but you would still have to know how to write
> a Scheme engraver.