Re: Proposed new available and recommended behavior of \relative

[Robert Schmaus]

On Fri, Mar 8, 2013, at 09:06 AM, David Kastrup wrote:
> Robert Schmaus <address@hidden> writes:
> 
> > Hi everyone,
> >
> > I haven't read all posts on this subject, so sorry should I write
> > something that's already been written.
> > Why not keep the \relative <pitch> { <music> } syntax as one supported
> > way and simply change the \relative { <music> } syntax to what David
> > proposed?
> 
> Uh, that was the plan anyway.  The question was rather whether we should
> convert to using the second form preferably in documentation and
> examples.

Oh, sorry, I interpreted your remark from an earlier mail ("But when
upgrading, convert-ly will convert it to the form without explicit pitch
if it can.") in that way, that the \relative <pitch> { <music> } is
planned to disappear ultimately.


> > I myself have always only used the first version (I didn't even know
> > the other existed, to be honest), and I liked the idea of having a
> > lever outside the music that shifted the music ocave-wise.
> 
> \transpose c c'' is such a lever.

I have thought of that too - it's just that transposition for me is
something I'd apply to a complete score in concert pitch e.g. to produce
a music sheet for Bb instruments. Something that comes after the actual
music writing process - in my understanding anyway. Of course, one can
use any command in lilypond however one sees fit ...


> > Or, as an alternative, the \relative { <music> } syntax could rely on
> > music that was written *before* the relative block.
> 
> That one is not an actual alternative.
> 
> xxx = \relative { c d e f g }
> yyy = \relative { c d e f g }
> 
> \new Voice { \yyy \xxx }
> 
> Now what is the music "written before the relative block"?  The whole
> point of \relative is that it returns absolute music given relative
> music.  You propose it should return relative music given relative
> music.  But how would music then become absolute?

It would, if there's either a default (pitch) for \relative { ... } with
no music before it. Or if the compiler gives an error if a user were to
write something like your example. After all, it's always up to the
typesetter to write something that makes sense.


> Making this proposal work in a sensible and predictable
> manner would be quite harder than it might appear.

There are probably not many persons who would know this better than you
do ... and I don't think that any of what lilypond can produce is quite
as easy as it appears! Each time I use it, I am amazed by something new!

Best,
Robert