Use make-engraver when feasible

[lilypond.git] / Documentation / snippets / new / defining-an-engraver-in-scheme-ambitus-engraver.ly

diff --git a/Documentation/snippets/new/defining-an-engraver-in-scheme-ambitus-engraver.ly b/Documentation/snippets/new/defining-an-engraver-in-scheme-ambitus-engraver.ly
index 379dc69147c3e608845aabccf44041bd0aff84c1..8958cd9e128f9f56a1261983465966afd98253be 100644 (file)
--- a/Documentation/snippets/new/defining-an-engraver-in-scheme-ambitus-engraver.ly
+++ b/Documentation/snippets/new/defining-an-engraver-in-scheme-ambitus-engraver.ly
@@ -1,4 +1,4 @@
-\version "2.14.0"
+\version "2.15.31"
 
 \header {
 
@@ -21,10 +21,6 @@
 %%% Grob utilities
 %%%
 %%% These are literal rewrites of some C++ methods used by the ambitus engraver.
-#(define (ly:event::in-event-class event class-name)
-   "Check if @var{event} the given class.
-Rewrite of @code{Stream_event::internal_in_event_class} from @file{lily/stream-event.cc}."
-   (memq class-name (ly:make-event-class (ly:event-property event 'class))))
 
 #(define (ly:separation-item::add-conditional-item grob grob-item)
    "Add @var{grob-item} to the array of conditional elements of @var{grob}.
@@ -188,7 +184,7 @@ position of middle C and key signature from @var{translator}'s context."
    ;; Get the event that caused the note-grob creation
    ;; and check that it is a note-event.
    (let ((note-event (ly:grob-property note-grob 'cause)))
-     (if (ly:event::in-event-class note-event 'note-event)
+     (if (ly:in-event-class? note-event 'note-event)
          ;; get the pitch from the note event
          (let ((pitch (ly:event-property note-event 'pitch)))
            ;; if this pitch is lower than the current ambitus lower
@@ -292,23 +288,24 @@ position of middle C and key signature from @var{translator}'s context."
    (lambda (context)
      (let ((ambitus #f))
        ;; when music is processed: make the ambitus object, if not already built
-       `((process-music . ,(lambda (translator)
-                             (if (not ambitus)
-                                 (set! ambitus (make-ambitus translator)))))
-         ;; set the ambitus clef and key signature state
-         (stop-translation-timestep . ,(lambda (translator)
-                                         (if ambitus
-                                             (initialize-ambitus-state ambitus translator))))
-         ;; when a note-head grob is built, update the ambitus notes
-         (acknowledgers
-          (note-head-interface . ,(lambda (engraver grob source-engraver)
-                                    (if ambitus
-                                        (update-ambitus-notes ambitus grob)))))
-         ;; finally, typeset the ambitus according to its upper and lower notes
-         ;; (if any).
-         (finalize . ,(lambda (translator)
-                        (if ambitus
-                            (typeset-ambitus ambitus translator))))))))
+       (make-engraver
+       ((process-music translator)
+        (if (not ambitus)
+            (set! ambitus (make-ambitus translator))))
+       ;; set the ambitus clef and key signature state
+       ((stop-translation-timestep translator)
+        (if ambitus
+            (initialize-ambitus-state ambitus translator)))
+       ;; when a note-head grob is built, update the ambitus notes
+       (acknowledgers
+          ((note-head-interface engraver grob source-engraver)
+          (if ambitus
+              (update-ambitus-notes ambitus grob))))
+       ;; finally, typeset the ambitus according to its upper and lower notes
+       ;; (if any).
+       ((finalize translator)
+        (if ambitus
+            (typeset-ambitus ambitus translator)))))))
 
 %%%
 %%% Example