problems with user-defined command line options

[Marc Hohl]

Hello list,

I have some files with songs where I want to switch the slurs on
and off.

After searching the docs, I came up with this:

optional-slurs.ly
==================

\version "2.15.23"

#(ly:add-option 'no-slurs #f
      "Whether to print a slur or not.")

slurSwitch = #(define-music-function (parser location) ()
   (if (eq? #t (ly:get-option 'no-slurs))
       #{ \override Slur #'transparent = ##t #}
       #{#}))

test = {
  \slurSwitch
  c2 ( d )
}

\score { \test }

==================

If I call it with

> lilypond optional-slurs.ly

everything is fine; when I use

> lilypind -d no-slurs optional-slurs.ly

I get a warning that option 'no-slurs is
undefined, and the slurs are still visible.

Searching in the archives showed

http://lists.gnu.org/archive/html/lilypond-devel/2009-11/msg00135.html
http://lists.gnu.org/archive/html/lilypond-devel/2008-02/msg00080.html

with no apparent solution.

Am I doing something wrong, or is lilypond faulty here?

Thanks in advance

Marc