Re: Create engravers for merging rests (issue 321930043 by address@hidden)

[horndude77]

https://codereview.appspot.com/321930043/diff/100001/scm/scheme-engravers.scm
File scm/scheme-engravers.scm (right):

https://codereview.appspot.com/321930043/diff/100001/scm/scheme-engravers.scm#newcode151
scm/scheme-engravers.scm:151: (define (rest-eqv rest-len-prop)
On 2017/05/20 12:18:33, thomasmorley651 wrote:
> The current patch-set fails with:
> "Variable used before given a value: rest-eqv"
> because subsequent usage of 'define ...' is equivalent to let not let*

> Moving (define (rest-eqv rest-len-prop) before the engraver-definiton
starts
> will work or something at the lines of

> ...
>    (let* ((rest-eqv
>             (lambda (rest-len-prop)
>               (define (rest-len rest) (ly:grob-property rest
rest-len-prop))
>               (lambda (rest-a rest-b)
>                 (eqv? (rest-len rest-a) (rest-len rest-b)))))
>           (mmrest-same-length (rest-eqv 'measure-count))
>           (rest-same-length (rest-eqv 'duration-log)))

>    (define (merge-mmrests rests)
> ...


Interesting. I didn't run into that error. I'm using the latest lilydev
which is using guile 2. That could be the difference. In any case I've
removed the methods so this shouldn't happen.

https://codereview.appspot.com/321930043/diff/100001/scm/scheme-engravers.scm#newcode167
scm/scheme-engravers.scm:167: (lambda (rest) (ly:grob-set-property! rest
'Y-offset (rest-offset rest)))
On 2017/05/20 14:33:15, david.nalesnik wrote:
> Just moving one rest on top of the other might cause offsets with some
printers.
>   This happened at one time with flags on chords: see
> http://lists.gnu.org/archive/html/bug-lilypond/2015-08/msg00080.html

> Would it work to set 'stencil of all of the cdr to point-stencil?

Using point-stencil causes odd alignment issues with text connected to
multimeasure rests. Making them invisible doesn't have this issue. Would
that solve the above potential problem?

Related to this, is there a way to re-parent grobs onto the surviving
rest? If so we could then use point-stencil (or possibly fully destroy)
the other rests.

https://codereview.appspot.com/321930043/diff/100001/scm/scheme-engravers.scm#newcode193
scm/scheme-engravers.scm:193: ((eq? 'MultiMeasureRest (grob::name grob))
On 2017/05/20 14:33:15, david.nalesnik wrote:
> The only two grobs you could get are Rest and MultiMeasureRest, so you
could
> just write

> (else
>    (set! [...]


> [I think looking at the grob name is fine.]

It was simple enough to switch over and use (else ...) as well.

https://codereview.appspot.com/321930043/