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

[thomasmorley65]

https://codereview.appspot.com/321930043/diff/60001/scm/merge-rests-engraver.scm
File scm/merge-rests-engraver.scm (right):

https://codereview.appspot.com/321930043/diff/60001/scm/merge-rests-engraver.scm#newcode10
scm/merge-rests-engraver.scm:10: (define (rest-length rest)
This definition is unused later and wouldn't work because of here
undefined 'rest-a'.
Maybe change it to something iterating over a list, comparing their
elements looking at their 'duration-log for Rests and 'measure-count for
MultiMeasureRests.
And use it for checking equal Rests/MMRs.

https://codereview.appspot.com/321930043/diff/60001/scm/merge-rests-engraver.scm#newcode23
scm/merge-rests-engraver.scm:23: (define-public merge-rests-engraver
Two general questions:
(1)
Is it possible to merge both engravers or is there a use case to have
them separated?
(2)
What do you think about introducing a property to switch rest-merging
on/off.
Could be a grob-property, both support rest-interface. Or probably a
context-property because the engraver(s) are in Staff.

https://codereview.appspot.com/321930043/diff/60001/scm/merge-rests-engraver.scm#newcode72
scm/merge-rests-engraver.scm:72: `((start-translation-timestep .
,(lambda (trans)
The order:
start-translation-timestep
stop-translation-timestep
finalize
acknowledgers
feels irritating and does not correspondend to the time they are called.
Any reason I for it, I'm not aware?

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