Re: Syntax: a2*2

[Mats Bengtsson]

> For what purpose serves the syntax 'a2*2'? The confuse was found in
> 
> \score { \notes { \time 4/4 a2*2   a1*3/4 a4 a1} } % multiplied durations,
> \score { \notes { \time 4/4 a1     a2.    a4 a1} } % where expected output
> \score { \notes { \time 4/4 a1 <a1 {s2. a4}> a1} } % got distorted (why?).

The idea of the a2*2 syntax is that the note itself (note head and
flags) is printed as the original a2 note, whereas the placement
of the notes is done as if the duration was twice that of a2.
You could see it just as a shorthand for \times 2 {a2}.
It may not sound too useful, but I've actually used it several 
times for example in cadenza-like situations where the composer
was a bit sloppy with the exact rhythm. Most common, though, is
when you have spacing notes in some voice: s1*12 or multimeasure
rests: R2.*30.

> This bug (?) was found also in another context:
> 
> \score { \notes { \time 12/4 \context Voice = i {
>     \repeat "tremolo" 6 { c8 es } s1. % While tremolos are repeated long
>     \repeat "tremolo" 12 { c8 es }}}} % enough, the duration is too short.

Well, that's a completely different matter. The problem is that 
you could easily input a \repeat tremolo instruct where there
is no standard notation. In your example you may claim that 
Lilypond could be smart enough to insert a bar line and and 
output two bars.Likewise, for
\repeat tremolo 5 {c16 es} 
it'd have to split into two separate chord tremolos with half note
and eigth note durations, respectively. In some cases this 
division can be done in several ways, so it's not trivial.

A first step, though, would be for Lilypond to warn about
situations it does not know how to handle. I try to put
together a patch.

> Imho, for a1. and for a1.*1 there should be the following note heads:
>    ___             ___
>   /   \    and  ||/   \||
>   \___/ o       ||\___/||o

Does a\breve. give you what you are looking for?

  /Mats