Re: Proposed new available and recommended behavior of \relative

[Graham Percival]

On Fri, Mar 08, 2013 at 06:29:34AM +0100, David Kastrup wrote:
> Graham Percival <address@hidden> writes:
> 
> > Whereas keeping the explicit initial pitch:
> >   \relative c' { c' c' }
> > the c' outside the {} means "middle C"
> > each c' inside the {} means "jump an octave higher"
> 
> Not every piece starts from c, and we had lots of discussions about what
> to do when it doesn't.  I think we promoted using \relative x''' { x for

Yes.

> this case so that one would not have to figure out the relation of x to
> c to figure out the starting pitch, and \relative x''' { x is really
> not more helpful than \relative { x'''.

I disagree.  In that case, the x''' *outside* the {} is interepted
as an absolute note, while all the xyz *inside* the {} are
interpreted as relative notes.


> Here are some examples from our code
> base:
> 
> \context Voice  \relative c'' {

The fact that this uses \context Voice tells me that it was
probably written before 2005 or so, since I don't use that
construct and would normally complain about it if I saw it in a
patch.  I am entirely unsurprised that there are flaws in the
docs.

> sopranoMusic = \relative c'' {
>   \clef "treble"
>   r4 d2 a4 | d4. d8 a2 | cis4 d cis2 |
> }

looks ok to me?

> What's the deal with that?  How is this helpful when the starting pitch
> is not specified in relation to a preceding pitch in a musical phrase
> but rather in relation to some phantasmagoric pitch not in relation to
> scale or melody?  There is no c' in the key signature, so why in the
> \relative statements?

I wouldn't complain if somebody wanted to change the c'' to an
d''.

> > I know that David knows this, but just to remind people, you can
> > absolutely do things like \relative a'' { a b } \relative f,, { f d }
> 
> And distribute the pitch information across two places possibly
> separated like
> 
> \relative a' << \new Voice \time 2/4 \key g\major \clef "treble" R1*20
> \tuplet 3/2 { r r r } \tuplet 3/2 { r as

Spread of information is certainly a valid concern.  That's why my
scores would generally look like this:

<<
  \new Voice {
    \time 2/4
    \key g\major
    \clef "treble"

    \relative a' {
      R1*20
      \tuplet 3/2 { r r r } \tuplet 3/2 { r as
    }
  }
>>


> And make no mistake: our code base does not show _any_ coherent usage of
> \relative.

That's no surprise to anybody familiar with the docs.

- Graham