Re: lilypond ChangeLog Documentation/user/examples....

[Erik Sandberg]

On Monday 18 September 2006 12:44, Han-Wen Nienhuys wrote:
> Erik Sandberg wrote:
> > How about
> > \score {
> >  { c d e }
> >  \midi{ pre = \tempo 4. = 70 }
> > }
> > ?
> >
> > (I.e., \tempo is a music expression => it's not a grammatical exception)
> >
> > Semantics: If pre is set, then embed main input in a SequentialMusic when
> > interpreting music for midi. So instead of interpreting { c d e } above,
> > we interpret the expression:
> > { \tempo 4.=70 { c d e } }
>
> This is a smart idea. Syntactically, I'm not a big fan of this (the
> double = is a little strange). However, it would be easy to encapsulate
> this with a Scheme expression,
>
>
>    #(set-midi-tempo "4." 70)
>
> however, we would need to have a separate music expression for each
> output block.

in that case, why not stick with the following, which already works?
\score { {\tempo 4.=70 \music} \midi {}}
\score { \music \layout {}}

> That would nicely match with a syntax change along the lines of
>
>
>    \withoutput \layout { .. } {music expression}
>
>    \withoutput \midi { .. } {music expression}
>
> This implies that music functions are definitely allowed to have side
> effects, so it's a syntax change that has some serious repercussions.

Similarly, why can't
  \withoutput \layout {} \music 
just be a function that returns a Score object (such as the one described 
above)?

-- 
Erik