using \offset with Slur.positions

[Werner LEMBERG]

[2.19.4]


Folks,


it seems that \offset can't be applied to `Slur.positions'.  Doing

  \relative c' {
  \once \offset positions #'(5 . 5) Slur
    c'2( c)
  }

I get

  Warnung: the property 'positions of #<Grob Slur > cannot be offset

Doing

  \relative c' {
  \once \offset Slur.positions #'(5 . 5)
    c'2( c)
  }

instead I get no warning, but there is no effect at all.  [This looks
like a buglet, since I would expect a warning, too.]

Why is that?  In most cases a slur's representation can be most easily
improved by modifying the start and end points.  Using the
`control-points' property is far more complicated IMHO.

A minor issue: Would it be possible to support

  \offset Slur.positions = #'(5 . 5)

as a syntax for to be in sync with \override?


    Werner