Re: Add the command \offset to LilyPond (issue 8647044)

[janek . lilypond]

On 2013/04/16 13:03:25, dak wrote:
> On 2013/04/16 12:50:47, david.nalesnik wrote:
> > Here I kept the same pattern as \alterBroken and \shape,
> > as they have been revised by David Kastrup.  I agree that
> > the syntax is a little awkward, and that
> > it would be nice if the pattern you give were workable.
> > However, IIRC, this syntax is the only one currently feasible.
> > I'm not an expert here, though.

> For \alterBroken and \shape, the syntax is actually
> \shape ... item where item is either music
> (which is then tweaked) _or_ a grob
> (which then gets an override).  The syntax
> is only due to this double-function.

> If \offset does not have the same characteristic (nor intends to have
it), then
> one should be able to make do with a single specification.

> I have not reviewed this so far, so I can't tell.

I've always thought that the syntax of \shape was done
this way because there was no "property" argument (as
it always concerned control-points) - in other words,
\shape's syntax is

\shape value grobname-or-music

because we need to keep the number and order of arguments
quite constant. The alternative (specifying grobname before
value) would be bad because then we'd have

\shape grobname-or-nothing value nothing-or-musc

and there's too many "or-nothing"s there (i suppose
that the biggest problem is an optional argument
followed by non-optional one ("value")).  However,
in case of \offset, we can have either a \shape-like
syntax

\offset property value grobname-or-music

or

\offset grobwithproperty-or-property value nothing-or-music

since the first argument is not optional (i.e there's
always at least the property to specify), i guess that
it should be easier to do?

best,
Janek

https://codereview.appspot.com/8647044/