Optional args in event-function not working with 2.17.6 ?

[Thomas Morley]

Hi,

I was working on
http://lists.gnu.org/archive/html/lilypond-user/2012-11/msg00185.html
and wrote a event-function as a template for custom-script-signs.
This function uses some optional arguments and works as expected in 2.16.0
But not in 2.17.6
What am I missing?

\version "2.16.0"

#(define (mrkp align arg)
#{
        \markup
          \fontsize #1.2
          \general-align #X #align
          \override #'(font-name . "TeXGyreSchola Bold")
          %\override #'(font-name . "Century Schoolbook L")
          \vcenter
          #arg

#})

newScript =
#(define-event-function (parser location lst scaling strg) ((list? '(0
0 0)) (boolean? #f) string?)
#{
        \tweak
          #'stencil
            #(lambda (grob)
              (let* ((dir (ly:grob-property grob 'direction))
                     (note-head (ly:grob-parent grob X))
                     (note-column (ly:grob-parent note-head Y))
                     (stem (ly:grob-object note-column 'stem))
                     (stem-dir (ly:grob-property stem 'direction))
                     (align (cond ((and (= stem-dir 1)(= dir 1))
                                   (car lst))
                                   ((and (= stem-dir -1)(= dir -1))
                                    (cadr lst))
                                   ((or (= stem-dir -1)(= dir -1))
                                    (car (last-pair lst)))
                                  (else 0)))
                     (new-stencil
                        (grob-interpret-markup grob
                           (mrkp align strg))))
              (ly:stencil-scale
              new-stencil
              1 (if scaling dir 1)
              )))
    -|
#})

% The arguments of the list dictate alignment-behaviour.
% First: If Stem- and Script-direction is UP.
% Second: If Stem- and Script-direction is DOWN.
% Third: If Stem- or Script-direction is DOWN
%
% LEFT   : -1
% RIGHT  : 1
% CENTER : 0
% Other value are possible.
%
% The list #'(0 0 0) could be omitted.
%
%
% If you want to mirror the script sign (while Script-direction is Down)
% add ##t, as shown in the examples.
% Otherwise it could be omitted too.

grave = \newScript #'(-1 0 0) ##t "`"
acute = \newScript #'(0 1 0) ##t "´"
threePoints = \newScript "…"
noName = \newScript "@"

\relative c' {
        c1\grave
        d\acute
        e\threePoints
        f\noName
}


Regards,
  Harm