Re: Implement optional music function arguments (issue 5023044)

[David Kastrup]

address@hidden writes:

> Looks pretty cool, apart from some involved Scheme which I couldn't
> really unravel totally (see below).
>
> Will this patch allow us to get rid of the abomination of
> \afterGraceFraction by recasting \afterGrace to have an optional
> parameter
> \afterGrace {note} {gracenotes} [spacing-fraction]

You'd rather have to make this

\afterGrace [spacing-fraction] {note} {gracenotes}

or similar.  I am not too clear on just what would work as an argument
type for spacing-fraction.  Scheme as in #'(15 . 16) or a duration as in
1*15/16 (ugh, what with the 1?).

Personally, I'd likely just go for
\afterGrace \times 15/16 {note} {gracenotes}

\afterGrace can easily check whether it gets scaled music and unpack
it.  If you really want to write scaled music, you can do so as
\afterGrace { \times 15/16 ...
in which case you get a sequential music event as topmost expression
which you leave alone.

This will turn out weird if you did
somemacro = \times 2/3 { .... }
and then use
\afterGrace \somemacro ...
because then you'll likely have no idea what happens.  Or if you do
\afterGrace on tuplets without bothering to enclose them in braces.

This would work fine without involving any functionality from this patch
series.

Or you do
\afterGrace [spacing-duration] ...

instead and forget about the fraction (durations can be fractions after
all).

-- 
David Kastrup