Re: \parenthesize and optional arguments

[Marc Hohl]

Am 04.07.2015 um 10:08 schrieb David Kastrup:
[...]
> Well, I'm not enthusiastic about both code and interface.

What about

\version "2.19.20"

#(define (set-paren-property arg)
   (if (memq 'event-chord (ly:music-property arg 'types))
       ;; arg is an EventChord -> set the parenthesize property
       ;; on all child notes and rests
       (for-each
        (lambda (ev)
          (if (or (memq 'note-event (ly:music-property ev 'types))
                  (memq 'rest-event (ly:music-property ev 'types)))
              (set! (ly:music-property ev 'parenthesize) #t)))
        (ly:music-property arg 'elements))
       ;; No chord, simply set property for this expression:
       (set! (ly:music-property arg 'parenthesize) #t)))

lparenthesize =
#(define-music-function (arg) (ly:music?)
   (_i "Tag @var{arg} to be left parenthesized.")
   (set-paren-property arg)

    #{ \tweak ParenthesesItem.stencils #(lambda (grob)
          (let ((par-list (parentheses-item::calc-parenthesis-stencils 
grob)))
          (list (car par-list) point-stencil))) #arg #})

rparenthesize =
#(define-music-function (arg) (ly:music?)
   (_i "Tag @var{arg} to be right parenthesized.")
   (set-paren-property arg)

    #{ \tweak ParenthesesItem.stencils #(lambda (grob)
          (let ((par-list (parentheses-item::calc-parenthesis-stencils 
grob)))
          (list point-stencil (cadr par-list)))) #arg #})

{ \parenthesize c \lparenthesize d \rparenthesize e
  c-\parenthesize-1 d-\lparenthesize-2 e-\rparenthesize-3}

I'd define set-paren-property globally at a appropriate place, rewrite
the definition of \parenthesize using set-paren-property and add
\[l|r]parenthesize.

Would that warrant a patch?

Cheers,

Marc