Re: Understanding how \tag works in \relative pitched music

[David Wright]

On Sun 06 Aug 2017 at 22:51:57 (+0200), David Kastrup wrote:
> David Wright <address@hidden> writes:
> 
> > (\fixed could have been implemented differently, ie without
> > collapsing the meaning of c' through b' as its first argument.
> > This might make it more useful for parts having a limited range
> > centered close to c.)
> 
> How so?  The reason we collapsed the meaning is that we had several
> different opinions of what the natural behavior of \fixed f' should be
> "obviously", so we punted by choosing behavior that did not provide
> (possibly shortlived) usefulness for anything rather than c'''.

As an example, some hymn tunes have alto parts of very limited range,
barely a few notes. However, those notes frequently lie around middle C
which means that both \fixed c and \fixed c' will have many octavation
marks, either "'" or ",". However, were \fixed g { … } to mean that
unmarked notes lie in the absolute range g through f', the number of
marks required would be drastically reduced, which is how I was measuring
usefulness. (I have no idea whether this methodology was one of the
"obvious natural behaviours" that were considered and passed over.)

> > Anyway, would the people who like \absolute please be a little less
> > evangelical about it.
> 
> Uh, where is the point?  This is a discussion group.

Yes, but there seem to be occasional postings where the opinions
come across as attempts at conversion rather than mere discussion. I
didn't want to be specific, but perhaps it's necessary for you—eg,
"There are many, many other reasons I'm glad I switched to absolute
(and \fixed), but this was a main one. You might consider doing the same?"

> > Some of us are happy using \relative, and understand how it interacts
> > (or, more usually, doesn't) with other constructions in LP. It's odd
> > that one of your main reasons for abandoning \relative was merely a
> > misunderstanding of what it does, but I think that that could partly
> > be blamed on its documentation. \relative's treatment of accidentals
> > merits bold typeface in the LM; perhaps its existence as an immediate
> > _input_ method could be similarly emphasised where appropriate.
> 
> \relative is a tool for expressing input.  As such, it should offer
> significant clarity with regard to one aspect of input.

And it succeeds in at least two for me. I've already mentioned one,
the treatment of intervals across b-c. Another is preventing LP code
looking like fly-shit language (cf Leaning Toothpick Syndrome).

> It doesn't do
> that impressively when communicating with other programs, so its main
> incentive is communication with humans.  When humans are confused about
> what it does, it fails on one of the core tenets of its justification.

That argument fails because not all humans are the same. The humans
that are confused are those that don't seem to learn/understand/
retain your sentence "\relative is a tool for expressing input."

> So its advantages are not without drawbacks, and people weighing in on
> how those affect them respectively are making for a clearer picture.

I'd be interested to know whether you agree with "the unpredictability
of \relative with \tag". I don't see it (as I expressed earlier), but
would value your opinion as you've probably forgotten more about LP
than I ever knew.

Cheers,
David.