Re: Some things need need to be fixed on the interfaces pages

[Christopher Heckman]

On Wed, Dec 11, 2024 at 10:58 PM Werner LEMBERG <wl@gnu.org> wrote:
>
> >> IIRC, a suggestion in the mentioned thread is to make the property
> >> description displayed for a given grob show which interfaces it is
> >> part of, for example
> >>
> >> ```
> >> ‘spacing-pair’ (pair)
> >>      interface(s):
> >>           centered-spanner-interface, multi-measure-interface
> [...]
> >>      default value:
> >>           '(break-alignment . break-alignment)
> >>
> >
> > There's a problem there, too, in that the default value depends on the grob.
> >
> > In MeasureSpanner, the default value is (staff-bar . staff-bar)
> >
> > In PercentRepeat, it's (break-alignment . staff-bar)
>
> I don't see a problem here.

You can't talk about *the* default value, because it's not unique; you
can only talk about *a* default value.

> For grob `foo`, it is completely
> irrelevant whether property `bar` is part of interface `xxx` or `yyy`.
> You access it as `foo.bar`.  Consequently, it is just a courtesy to
> the reader to mention which interface a property is part of.
>
> Maybe a grob description on the page showing the available default
> properties for `MeasureSpanner` could be displayed [...]
>

The default values seem to be set in grobs, not interfaces, so as an
alternative, how about something like ...

 ‘spacing-pair’ (pair)
      A pair of alignment symbols which set an object's spacing
      relative to its left and right ‘BreakAlignment’s.

      interface(s):
           centered-spanner-interface, multi-measure-interface
      default value in grob(s):
           CenteredBarNumber: [none]
           MeasureCounter: '(break-alignment . break-alignment)
           MultiMeasureRest: '(break-alignment . break-alignment)
           PercentRepeat: '(break-alignment . staff-bar)

(with the appropriate links added)

> >>> And there's actually precedent, in that left-handed chord diagrams
> >>> (FretBoards) are supported by Lilypond.
> >>
> >> Well, this makes sense, because they are displayed differently.
> >
> > Also, there's a grob named StrokeFinger.  It's not named
> > RightHandFinger.
>
> This is admittedly an inconsistency and could be fixed.  However, I'm
> not sure whether it is worth the cost: Renaming stuff forces all
> LilyPond users to re-learn commands that exist since a long time.
> Normally, we only do this only if there is confusing terminology (see
> the parallel thread about musical duration, moments, etc.)  In this
> case, however, it will IMHO suffice to mention that LilyPond uses the
> term 'right hand' for the strumming hand.
>
> A user can also very easily define new commands that better fits the
> intended purpose, for example,
>
> ```
> strummingHandFinger = \rightHandFinger
> ```

Yes. Also, I guess not as many left-handed players are upset about
this as I thought.

--- Christopher Carl Heckman