X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=scm%2Fmusic-functions.scm;h=31b6c8ad3c48d3861b3ffe500b8a1c6d2f627d76;hb=bf707a03756021f69e3f5d1a8246639a6a601099;hp=234faf41b5c40ac3237133971a76d855fe3542a4;hpb=086cfb9aebcd5a68cc5186a0103aa270037f0570;p=lilypond.git

diff --git a/scm/music-functions.scm b/scm/music-functions.scm
index 234faf41b5..31b6c8ad3c 100644
--- a/scm/music-functions.scm
+++ b/scm/music-functions.scm
@@ -1,11 +1,22 @@
-;;;; music-functions.scm --
+;;;; This file is part of LilyPond, the GNU music typesetter.
 ;;;;
-;;;;  source file of the GNU LilyPond music typesetter
-;;;; 
-;;;; (c) 1998--2006 Jan Nieuwenhuizen <janneke@gnu.org>
+;;;; Copyright (C) 1998--2011 Jan Nieuwenhuizen <janneke@gnu.org>
 ;;;;                 Han-Wen Nienhuys <hanwen@xs4all.nl>
+;;;;
+;;;; LilyPond is free software: you can redistribute it and/or modify
+;;;; it under the terms of the GNU General Public License as published by
+;;;; the Free Software Foundation, either version 3 of the License, or
+;;;; (at your option) any later version.
+;;;;
+;;;; LilyPond is distributed in the hope that it will be useful,
+;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;;; GNU General Public License for more details.
+;;;;
+;;;; You should have received a copy of the GNU General Public License
+;;;; along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
 
-;; (use-modules (ice-9 optargs)) 
+;; (use-modules (ice-9 optargs))
 
 ;;; ly:music-property with setter
 ;;; (ly:music-property my-music 'elements)
@@ -25,18 +36,30 @@
   (make-procedure-with-setter ly:grob-property
 			      ly:grob-set-property!))
 
+(define-public ly:grob-object
+  (make-procedure-with-setter ly:grob-object
+			      ly:grob-set-object!))
+
+(define-public ly:grob-parent
+  (make-procedure-with-setter ly:grob-parent
+			      ly:grob-set-parent!))
+
 (define-public ly:prob-property
   (make-procedure-with-setter ly:prob-property
 			      ly:prob-set-property!))
 
+(define-public ly:context-property
+  (make-procedure-with-setter ly:context-property
+			      ly:context-set-property!))
+
 (define-public (music-map function music)
   "Apply @var{function} to @var{music} and all of the music it contains.
 
-First it recurses over the children, then the function is applied to MUSIC.
-"
+First it recurses over the children, then the function is applied to
+@var{music}."
   (let ((es (ly:music-property music 'elements))
 	(e (ly:music-property music 'element)))
-    (set! (ly:music-property music 'elements) 
+    (set! (ly:music-property music 'elements)
 	  (map (lambda (y) (music-map function y)) es))
     (if (ly:music? e)
 	(set! (ly:music-property music 'element)
@@ -44,8 +67,8 @@ First it recurses over the children, then the function is applied to MUSIC.
     (function music)))
 
 (define-public (music-filter pred? music)
-  "Filter out music expressions that do not satisfy PRED."
-  
+  "Filter out music expressions that do not satisfy @var{pred?}."
+
   (define (inner-music-filter pred? music)
     "Recursive function."
     (let* ((es (ly:music-property music 'elements))
@@ -73,10 +96,11 @@ First it recurses over the children, then the function is applied to MUSIC.
       (make-music 'Music)))	  ;must return music.
 
 (define-public (display-music music)
-  "Display music, not done with music-map for clarity of presentation."
+  "Display music, not done with @code{music-map} for clarity of
+presentation."
 
   (display music)
-  (display ": { ")  
+  (display ": { ")
   (let ((es (ly:music-property music 'elements))
 	(e (ly:music-property music 'element)))
     (display (ly:music-mutable-properties music))
@@ -96,7 +120,7 @@ First it recurses over the children, then the function is applied to MUSIC.
 ;;;
 (define (markup-expression->make-markup markup-expression)
   "Transform `markup-expression' into an equivalent, hopefuly readable, scheme expression.
-For instance, 
+For instance,
   \\markup \\bold \\italic hello
 ==>
   (markup #:line (#:bold (#:italic (#:simple \"hello\"))))"
@@ -111,7 +135,7 @@ For instance,
 	  ((and (not (string? arg)) (markup? arg)) ;; a markup
 	   (inner-markup->make-markup arg))
 	  (else					 ;; scheme arg
-	   arg)))
+	   (music->make-music arg))))
   (define (inner-markup->make-markup mrkup)
     (if (string? mrkup)
 	`(#:simple ,mrkup)
@@ -124,14 +148,15 @@ For instance,
       `(markup ,@(inner-markup->make-markup markup-expression))))
 
 (define-public (music->make-music obj)
-  "Generate a expression that, once evaluated, may return an object equivalent to `obj',
-that is, for a music expression, a (make-music ...) form."
+  "Generate an expression that, once evaluated, may return an object
+equivalent to @var{obj}, that is, for a music expression, a
+@code{(make-music ...)} form."
   (cond (;; markup expression
 	 (markup? obj)
 	 (markup-expression->make-markup obj))
 	(;; music expression
 	 (ly:music? obj)
-	 `(make-music 
+	 `(make-music
 	   ',(ly:music-property obj 'name)
 	   ,@(apply append (map (lambda (prop)
                                   `(',(car prop)
@@ -170,7 +195,7 @@ that is, for a music expression, a (make-music ...) form."
 	 `(list ,@(map music->make-music obj)))
 	(;; a pair
 	 (pair? obj)
-	 `(cons ,(music->make-music (car obj)) 
+	 `(cons ,(music->make-music (car obj))
 		,(music->make-music (cdr obj))))
 	(else
 	 obj)))
@@ -204,9 +229,9 @@ Returns `obj'.
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (define-public (shift-one-duration-log music shift dot)
-  "  add SHIFT to duration-log of 'duration in music and optionally 
-  a dot to any note encountered. This scales the music up by a factor 
-  2^shift * (2 - (1/2)^dot)"
+  "Add @var{shift} to @code{duration-log} of @code{'duration} in
+@var{music} and optionally @var{dot} to any note encountered.  This
+scales the music up by a factor `2^@var{shift} * (2 - (1/2)^@var{dot})'."
   (let ((d (ly:music-property music 'duration)))
     (if (ly:duration? d)
 	(let* ((cp (ly:duration-factor d))
@@ -222,7 +247,22 @@ Returns `obj'.
 	     music))
 
 (define-public (make-repeat name times main alts)
-  "create a repeat music expression, with all properties initialized properly"
+  "Create a repeat music expression, with all properties initialized
+properly."
+  (define (first-note-duration music)
+    "Finds the duration of the first NoteEvent by searching depth-first
+through MUSIC."
+    (if (memq 'note-event (ly:music-property music 'types))
+	(ly:music-property music 'duration)
+	(let loop ((elts (if (ly:music? (ly:music-property music 'element))
+			     (list (ly:music-property music 'element))
+			     (ly:music-property music 'elements))))
+	  (and (pair? elts)
+	       (let ((dur (first-note-duration (car elts))))
+		 (if (ly:duration? dur)
+		     dur
+		     (loop (cdr elts))))))))
+
   (let ((talts (if (< times (length alts))
 		   (begin
 		     (ly:warning (_ "More alternatives than repeats.  Junking excess alternatives"))
@@ -232,35 +272,54 @@ Returns `obj'.
     (set! (ly:music-property r 'element) main)
     (set! (ly:music-property r 'repeat-count) (max times 1))
     (set! (ly:music-property r 'elements) talts)
-    (if (equal? name "tremolo")
-	(let* ((dot? (zero? (modulo times 3)))
-	       (dots (if dot? 1 0))
-	       (mult (if dot?
-			 (quotient (* times 2) 3)
-			 times))
-	       (shift (- (ly:intlog2 mult))))
-	  
-	  (if (memq 'sequential-music (ly:music-property main 'types))
-	      ;; \repeat "tremolo" { c4 d4 }
-	      (let ((children (length (ly:music-property main 'elements))))
-
-		;; fixme: should be more generic.
-		(if (and (not (= children 2))
-			 (not (= children 1)))
-		    (ly:warning (_ "expecting 2 elements for chord tremolo, found ~a") children))
-		(ly:music-compress r (ly:make-moment 1 children))
-		(shift-duration-log r
-				    (if (= children 2)  (1- shift) shift)
-				    dots))
-	      ;; \repeat "tremolo" c4
-	      (shift-duration-log r shift dots)))
+    (if (and (equal? name "tremolo")
+	     (or (pair? (ly:music-property main 'elements))
+		 (ly:music? (ly:music-property main 'element))))
+	;; This works for single-note and multi-note tremolos!
+	(let* ((children (if (music-is-of-type? main 'sequential-music)
+			     ;; \repeat tremolo n { ... }
+			     (length (ly:music-property main 'elements))
+			     ;; \repeat tremolo n c4
+			     1))
+	       ;; # of dots is equal to the 1 in bitwise representation (minus 1)!
+	       (dots (1- (logcount (* times children))))
+	       ;; The remaining missing multiplicator to scale the notes by
+	       ;; times * children
+	       (mult (/ (* times children (ash 1 dots)) (1- (ash 2 dots))))
+	       (shift (- (ly:intlog2 (floor mult))))
+	       (note-duration (first-note-duration r))
+	       (duration-log (if (ly:duration? note-duration)
+				 (ly:duration-log note-duration)
+				 1))
+	       (tremolo-type (ash 1 duration-log)))
+	  (set! (ly:music-property r 'tremolo-type) tremolo-type)
+	  (if (not (integer?  mult))
+              (ly:warning (_ "invalid tremolo repeat count: ~a") times))
+	  ;; Adjust the time of the notes
+	  (ly:music-compress r (ly:make-moment 1 children))
+	  ;; Adjust the displayed note durations
+	  (shift-duration-log r shift dots))
 	r)))
 
+(define (calc-repeat-slash-count music)
+  "Given the child-list @var{music} in @code{PercentRepeatMusic},
+calculate the number of slashes based on the durations.  Returns @code{0}
+if durations in in @var{music} vary, allowing slash beats and double-percent
+beats to be distinguished."
+  (let* ((durs (map (lambda (elt)
+		      (duration-of-note elt))
+		    (extract-named-music music 'EventChord)))
+	 (first-dur (car durs)))
+
+    (if (every (lambda (d) (equal? d first-dur)) durs)
+	(max (- (ly:duration-log first-dur) 2) 1)
+	0)))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; clusters.
 
 (define-public (note-to-cluster music)
-  "Replace NoteEvents by ClusterNoteEvents."
+  "Replace @code{NoteEvents} by @code{ClusterNoteEvents}."
   (if (eq? (ly:music-property music 'name) 'NoteEvent)
       (make-music 'ClusterNoteEvent
 		  'pitch (ly:music-property music 'pitch)
@@ -274,39 +333,38 @@ Returns `obj'.
 ;; repeats.
 
 (define-public (unfold-repeats music)
-  "
-This function replaces all repeats  with unfold repeats. "
+  "Replace all repeats with unfolded repeats."
 
   (let ((es (ly:music-property music 'elements))
-	(e  (ly:music-property music 'element))
-	)
-    (if (memq 'repeated-music (ly:music-property music 'types))
-	(let*
-	    ((props (ly:music-mutable-properties music))
-	     (old-name (ly:music-property music 'name))
-	     (flattened  (flatten-alist props)))
+	(e (ly:music-property music 'element)))
 
+    (if (memq 'repeated-music (ly:music-property music 'types))
+	(let* ((props (ly:music-mutable-properties music))
+	       (old-name (ly:music-property music 'name))
+	       (flattened (flatten-alist props)))
 	  (set! music (apply make-music (cons 'UnfoldedRepeatedMusic
 					      flattened)))
 
 	  (if (equal? old-name 'TremoloRepeatedMusic)
 	      (let* ((seq-arg? (memq 'sequential-music
 				     (ly:music-property e 'types)))
-		     (count  (ly:music-property music 'repeat-count))
+		     (count (ly:music-property music 'repeat-count))
 		     (dot-shift (if (= 0 (remainder count 3))
-				    -1 0)))
+				    -1 0))
+		     (child-count (if seq-arg?
+				      (length (ly:music-property e 'elements))
+				      0)))
 
 		(if (= 0 -1)
 		    (set! count (* 2 (quotient count 3))))
-		
-		(shift-duration-log music (+ (if seq-arg? 1 0)
+
+		(shift-duration-log music (+ (if (= 2 child-count)
+						 1 0)
 					     (ly:intlog2 count)) dot-shift)
-		
+
 		(if seq-arg?
-		    (ly:music-compress e (ly:make-moment (length (ly:music-property
-								  e 'elements)) 1)))))))
-	  
-    
+		    (ly:music-compress e (ly:make-moment child-count 1)))))))
+
     (if (pair? es)
 	(set! (ly:music-property music 'elements)
 	      (map unfold-repeats es)))
@@ -319,8 +377,8 @@ This function replaces all repeats  with unfold repeats. "
 ;; property setting music objs.
 
 (define-public (make-grob-property-set grob gprop val)
-  "Make a Music expression that sets GPROP to VAL in GROB. Does a pop first,
-i.e.  this is not an override"
+  "Make a @code{Music} expression that sets @var{gprop} to @var{val} in
+@var{grob}.  Does a pop first, i.e., this is not an override."
   (make-music 'OverrideProperty
 	      'symbol grob
 	      'grob-property gprop
@@ -328,21 +386,32 @@ i.e.  this is not an override"
 	      'pop-first #t))
 
 (define-public (make-grob-property-override grob gprop val)
-  "Make a Music expression that sets GPROP to VAL in GROB. Does a pop first,
-i.e.  this is not an override"
+  "Make a @code{Music} expression that overrides @var{gprop} to @var{val}
+in @var{grob}."
   (make-music 'OverrideProperty
 	      'symbol grob
 	      'grob-property gprop
 	      'grob-value val))
 
 (define-public (make-grob-property-revert grob gprop)
-  "Revert the grob property GPROP for GROB."
+  "Revert the grob property @var{gprop} for @var{grob}."
   (make-music 'RevertProperty
 	      'symbol grob
 	      'grob-property gprop))
 
 (define direction-polyphonic-grobs
-  '(Stem Tie Rest Slur PhrasingSlur Script TextScript Dots DotColumn Fingering))
+  '(DotColumn
+    Dots
+    Fingering
+    LaissezVibrerTie
+    PhrasingSlur
+    RepeatTie
+    Rest
+    Script
+    Slur
+    Stem
+    TextScript
+    Tie))
 
 (define-safe-public (make-voice-props-set n)
   (make-sequential-music
@@ -351,20 +420,37 @@ i.e.  this is not an override"
 					     (if (odd? n) -1 1)))
 	 direction-polyphonic-grobs)
     (list
+     (make-property-set 'graceSettings
+			;; TODO: take this from voicedGraceSettings or similar.
+			'((Voice Stem font-size -3)
+			  (Voice NoteHead font-size -3)
+			  (Voice TabNoteHead font-size -4)
+			  (Voice Dots font-size -3)
+			  (Voice Stem length-fraction 0.8)
+			  (Voice Stem no-stem-extend #t)
+			  (Voice Beam beam-thickness 0.384)
+			  (Voice Beam length-fraction 0.8)
+			  (Voice Accidental font-size -4)
+			  (Voice AccidentalCautionary font-size -4)
+			  (Voice Script font-size -3)
+			  (Voice Fingering font-size -8)
+			  (Voice StringNumber font-size -8)))
+
      (make-grob-property-set 'NoteColumn 'horizontal-shift (quotient n 2))
-     (make-grob-property-set 'MultiMeasureRest 'staff-position (if (odd? n) -4 4)))))) 
+     (make-grob-property-set 'MultiMeasureRest 'staff-position (if (odd? n) -4 4))))))
 
 (define-safe-public (make-voice-props-revert)
   (make-sequential-music
    (append
     (map (lambda (x) (make-grob-property-revert x 'direction))
 	 direction-polyphonic-grobs)
-    (list (make-grob-property-revert 'NoteColumn 'horizontal-shift))
-    (list (make-grob-property-revert 'MultiMeasureRest 'staff-position)))))
+    (list (make-property-unset 'graceSettings)
+	  (make-grob-property-revert 'NoteColumn 'horizontal-shift)
+	  (make-grob-property-revert 'MultiMeasureRest 'staff-position)))))
 
 
 (define-safe-public (context-spec-music m context #:optional id)
-  "Add \\context CONTEXT = ID to M. "
+  "Add \\context CONTEXT = ID to M."
   (let ((cm (make-music 'ContextSpeccedMusic
 			'element m
 			'context-type context)))
@@ -373,7 +459,7 @@ i.e.  this is not an override"
     cm))
 
 (define-public (descend-to-context m context)
-  "Like context-spec-music, but only descending. "
+  "Like @code{context-spec-music}, but only descending."
   (let ((cm (context-spec-music m context)))
     (ly:music-set-property! cm 'descend-only #t)
     cm))
@@ -423,87 +509,23 @@ i.e.  this is not an override"
   (make-music 'PropertyUnset
 	      'symbol sym))
 
-(define-public (make-ottava-set octavation)
-  (let ((m (make-music 'ApplyContext)))
-    (define (ottava-modify context)
-      "Either reset middleCPosition to the stored original, or remember
-old middleCPosition, add OCTAVATION to middleCPosition, and set
-OTTAVATION to `8va', or whatever appropriate."	    
-      (if (number? (ly:context-property	 context 'middleCPosition))
-	  (begin
-	    (if (number? (ly:context-property context 'originalMiddleCPosition))
-		(let ((where (ly:context-property-where-defined context 'middleCPosition)))
-		  
-		  (ly:context-set-property! context 'middleCPosition
-					    (ly:context-property context 'originalMiddleCPosition))
-		  (ly:context-unset-property where 'originalMiddleCPosition)
-		  (ly:context-unset-property where 'ottavation)))
-ot	    
-	    (let* ((where (ly:context-property-where-defined context 'middleCPosition))
-		   (c0 (ly:context-property context 'middleCPosition))
-		   (new-c0 (+ c0 (* -7 octavation)))
-		   (string (cdr (assoc octavation '((2 . "15ma")
-						    (1 . "8va")
-						    (0 . #f)
-						    (-1 . "8vb")
-						    (-2 . "15mb"))))))
-	      (ly:context-set-property! context 'middleCPosition new-c0)
-	      (ly:context-set-property! context 'originalMiddleCPosition c0)
-	      (ly:context-set-property! context 'ottavation string)))))
-    (set! (ly:music-property m 'procedure) ottava-modify)
-    (context-spec-music m 'Staff)))
-
-(define-public (set-octavation ottavation)
-  (ly:export (make-ottava-set ottavation)))
-
-(define-public (make-time-signature-set num den . rest)
-  "Set properties for time signature NUM/DEN.  Rest can contain a list
-of beat groupings "
-
-  (define (standard-beat-grouping num den)
-
-    "Some standard subdivisions for time signatures."
-    (let*
-	((key (cons num den))
-	 (entry (assoc key '(((6 . 8) . (3 3))
-			 ((5 . 8) . (3 2))
-			 ((9 . 8) . (3 3 3))
-			 ((12 . 8) . (3 3 3 3))
-			 ((8 . 8) . (3 3 2))
-			 ))))
-
-      (if entry
-	  (cdr entry)
-	  '())))    
-  
-  (let* ((set1 (make-property-set 'timeSignatureFraction (cons num den)))
-	 (beat (ly:make-moment 1 den))
-	 (len  (ly:make-moment num den))
-	 (set2 (make-property-set 'beatLength beat))
-	 (set3 (make-property-set 'measureLength len))
-	 (set4 (make-property-set 'beatGrouping (if (pair? rest)
-						    (car rest)
-						    (standard-beat-grouping num den))))
-	 (basic	 (list set1 set2 set3 set4)))
-    (descend-to-context
-     (context-spec-music (make-sequential-music basic) 'Timing) 'Score)))
-
-(define-public (make-mark-set label)
-  "Make the music for the \\mark command."  
-  (let* ((set (if (integer? label)
-		  (context-spec-music (make-property-set 'rehearsalMark label)
-				      'Score)
-		  #f))
-	 (ev (make-music 'MarkEvent))
-	 (ch (make-event-chord (list ev))))
-    (if set
-	(make-sequential-music (list set ch))
-	(begin
-	  (set! (ly:music-property ev 'label) label)
-	  ch))))
+;;; Need to keep this definition for \time calls from parser
+(define-public (make-time-signature-set num den)
+  "Set properties for time signature @var{num}/@var{den}."
+  (make-music 'TimeSignatureMusic
+              'numerator num
+              'denominator den
+              'beat-structure '()))
 
+;;; Used for calls that include beat-grouping setting
 (define-public (set-time-signature num den . rest)
-  (ly:export (apply make-time-signature-set `(,num ,den . ,rest))))
+  "Set properties for time signature @var{num}/@var{den}.
+If @var{rest} is present, it is used to set @code{beatStructure}."
+  (ly:export
+   (make-music 'TimeSignatureMusic
+	       'numerator num
+	       'denominator den
+	       'beat-structure (if (null? rest) rest (car rest)))))
 
 (define-safe-public (make-articulation name)
   (make-music 'ArticulationEvent
@@ -518,15 +540,50 @@ of beat groupings "
   (make-music type
 	      'span-direction span-dir))
 
-(define-public (set-mus-properties! m alist)
-  "Set all of ALIST as properties of M." 
+(define-public (override-head-style heads style)
+  "Override style for @var{heads} to @var{style}."
+  (make-sequential-music
+    (if (pair? heads)
+        (map (lambda (h)
+              (make-grob-property-override h 'style style))
+         heads)
+        (list (make-grob-property-override heads 'style style)))))
+
+(define-public (revert-head-style heads)
+  "Revert style for @var{heads}."
+  (make-sequential-music
+    (if (pair? heads)
+        (map (lambda (h)
+              (make-grob-property-revert h 'style))
+         heads)
+        (list (make-grob-property-revert heads 'style)))))
+
+(define-public (style-note-heads heads style music)
+ "Set @var{style} for all @var{heads} in @var{music}.  Works both
+inside of and outside of chord construct."
+  ;; are we inside a <...>?
+  (if (eq? (ly:music-property music 'name) 'NoteEvent)
+      ;; yes -> use a tweak
+      (begin
+        (set! (ly:music-property music 'tweaks)
+              (acons 'style style (ly:music-property music 'tweaks)))
+        music)
+      ;; not in <...>, so use overrides
+      (make-sequential-music
+        (list
+          (override-head-style heads style)
+          music
+          (revert-head-style heads)))))
+
+ (define-public (set-mus-properties! m alist)
+  "Set all of @var{alist} as properties of @var{m}."
   (if (pair? alist)
       (begin
 	(set! (ly:music-property m (caar alist)) (cdar alist))
 	(set-mus-properties! m (cdr alist)))))
 
 (define-public (music-separator? m)
-  "Is M a separator?"
+  "Is @var{m} a separator?"
   (let ((ts (ly:music-property m 'types)))
     (memq 'separator ts)))
 
@@ -534,10 +591,10 @@ of beat groupings "
 (define (voicify-list lst number)
   "Make a list of Musics.
 
-   voicify-list :: [ [Music ] ] -> number -> [Music]
-   LST is a list music-lists.
+voicify-list :: [ [Music ] ] -> number -> [Music]
+LST is a list music-lists.
 
-   NUMBER is 0-base, i.e. Voice=1 (upstems) has number 0.
+NUMBER is 0-base, i.e., Voice=1 (upstems) has number 0.
 "
   (if (null? lst)
       '()
@@ -545,7 +602,7 @@ of beat groupings "
 	     (make-sequential-music
 	      (list (make-voice-props-set number)
 		    (make-simultaneous-music (car lst))))
-	     'Voice  (number->string (1+ number)))
+	     'Bottom  (number->string (1+ number)))
 	    (voicify-list (cdr lst) (1+ number)))))
 
 (define (voicify-chord ch)
@@ -556,7 +613,7 @@ of beat groupings "
     ch))
 
 (define-public (voicify-music m)
-  "Recursively split chords that are separated with \\ "
+  "Recursively split chords that are separated with @code{\\\\}."
   (if (not (ly:music? m))
       (ly:error (_ "music expected: ~S") m))
   (let ((es (ly:music-property m 'elements))
@@ -573,14 +630,11 @@ of beat groupings "
 
 (define-public (empty-music)
   (ly:export (make-music 'Music)))
-;;;
 
-					; Make a function that checks score element for being of a specific type. 
+;; Make a function that checks score element for being of a specific type.
 (define-public (make-type-checker symbol)
   (lambda (elt)
-    ;;(display	symbol)
-    ;;(eq? #t (ly:grob-property elt symbol))
-    (not (eq? #f (memq symbol (ly:grob-property elt 'interfaces))))))
+    (grob::has-interface elt symbol)))
 
 (define-public ((outputproperty-compatibility func sym val) grob g-context ao-context)
   (if (func grob)
@@ -588,25 +642,20 @@ of beat groupings "
 
 
 (define-public ((set-output-property grob-name symbol val)  grob grob-c context)
-  "Usage:
-
-\\applyoutput #(set-output-property 'Clef 'extra-offset '(0 . 1))
-
-"
+  "Usage example:
+@code{\\applyoutput #(set-output-property 'Clef 'extra-offset '(0 . 1))}"
   (let ((meta (ly:grob-property grob 'meta)))
-    (if (equal?  (cdr (assoc 'name meta)) grob-name)
+    (if (equal? (assoc-get 'name meta) grob-name)
 	(set! (ly:grob-property grob symbol) val))))
 
 
 ;;
 (define-public (smart-bar-check n)
-  "Make	 a bar check that checks for a specific bar number. 
-"
+  "Make a bar check that checks for a specific bar number."
   (let ((m (make-music 'ApplyContext)))
     (define (checker tr)
       (let* ((bn (ly:context-property tr 'currentBarNumber)))
-	(if (= bn n)
-	    #t
+	(or (= bn n)
 	    (ly:error
 	     ;; FIXME: uncomprehensable message
 	     (_ "Bar check failed.  Expect to be at ~a, instead at ~a")
@@ -616,23 +665,32 @@ of beat groupings "
 
 
 (define-public (skip->rest mus)
+  "Replace @var{mus} by @code{RestEvent} of the same duration if it is a
+@code{SkipEvent}.  Useful for extracting parts from crowded scores."
 
-  "Replace MUS by RestEvent of the same duration if it is a
-SkipEvent. Useful for extracting parts from crowded scores"
-
-  (if (equal? (ly:music-property mus 'name) 'SkipEvent)
+  (if  (memq (ly:music-property mus 'name) '(SkipEvent SkipMusic))
    (make-music 'RestEvent 'duration (ly:music-property mus 'duration))
    mus))
 
 
+(define-public (music-has-type music type)
+  (memq type (ly:music-property music 'types)))
+
+(define-public (music-clone music)
+  (define (alist->args alist acc)
+    (if (null? alist)
+	acc
+	(alist->args (cdr alist)
+		     (cons (caar alist) (cons (cdar alist) acc)))))
+
+  (apply
+   make-music
+   (ly:music-property music 'name)
+   (alist->args (ly:music-mutable-properties music) '())))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; warn for bare chords at start.
 
-(define (has-request-chord elts)
-  (reduce (lambda (x y) (or x y)) #f
-	  (map (lambda (x)
-		 (equal? (ly:music-property x 'name) 'RequestChord))
-	       elts)))
 
 (define-public (ly:music-message music msg)
   (let ((ip (ly:music-property music 'origin)))
@@ -640,25 +698,6 @@ SkipEvent. Useful for extracting parts from crowded scores"
 	(ly:input-message ip msg)
 	(ly:warning msg))))
 
-(define (check-start-chords music)
-  "Check music expression for a Simultaneous_music containing notes\n(ie. Request_chords),
-without context specification. Called  from parser."
-  (let ((es (ly:music-property music 'elements))
-	(e (ly:music-property music 'element))
-	(name (ly:music-property music 'name)))
-    (cond ((equal? name "Context_specced_music") #t)
-	  ((equal? name "Simultaneous_music")
-	   (if (has-request-chord es)
-	       (ly:music-message music "Starting score with a chord.\nInsert an explicit \\context before chord")
-	       (map check-start-chords es)))
-	  ((equal? name "SequentialMusic")
-	   (if (pair? es)
-	       (check-start-chords (car es))))
-	  (else (if (ly:music? e) (check-start-chords e)))))
-  music)
-
-
-
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;
 ;; setting stuff for grace context.
@@ -673,21 +712,20 @@ without context specification. Called  from parser."
     nv))
 
 (define (vector-map f v)
-  "Map	F over V. This function returns nothing."
+  "Map F over V.  This function returns nothing."
   (do ((n (vector-length v))
        (i 0 (+ i 1)))
       ((>= i n))
     (f (vector-ref v i))))
 
 (define (vector-reverse-map f v)
-  "Map	F over V, N to 0 order. This function returns nothing."
+  "Map F over V, N to 0 order.  This function returns nothing."
   (do ((i (- (vector-length v) 1) (- i 1)))
       ((< i 0))
     (f (vector-ref v i))))
 
-;; TODO:  make a remove-grace-property too.
 (define-public (add-grace-property context-name grob sym val)
-  "Set SYM=VAL for GROB in CONTEXT-NAME. "
+  "Set @var{sym}=@var{val} for @var{grob} in @var{context-name}."
   (define (set-prop context)
     (let* ((where (ly:context-property-where-defined context 'graceSettings))
 	   (current (ly:context-property where 'graceSettings))
@@ -696,10 +734,31 @@ without context specification. Called  from parser."
       (ly:context-set-property! where 'graceSettings new-settings)))
   (ly:export (context-spec-music (make-apply-context set-prop) 'Voice)))
 
+(define-public (remove-grace-property context-name grob sym)
+  "Remove all @var{sym} for @var{grob} in @var{context-name}."
+  (define (sym-grob-context? property sym grob context-name)
+    (and (eq? (car property) context-name)
+         (eq? (cadr property) grob)
+         (eq? (caddr property) sym)))
+  (define (delete-prop context)
+    (let* ((where (ly:context-property-where-defined context 'graceSettings))
+	   (current (ly:context-property where 'graceSettings))
+           (prop-settings (filter
+                            (lambda(x) (sym-grob-context? x sym grob context-name))
+                            current))
+	   (new-settings current))
+      (for-each (lambda(x)
+                 (set! new-settings (delete x new-settings)))
+               prop-settings)
+      (ly:context-set-property! where 'graceSettings new-settings)))
+  (ly:export (context-spec-music (make-apply-context delete-prop) 'Voice)))
+
 
 
-(defmacro-public def-grace-function (start stop)
+(defmacro-public def-grace-function (start stop . docstring)
+  "Helper macro for defining grace music"
   `(define-music-function (parser location music) (ly:music?)
+     ,@docstring
      (make-music 'GraceMusic
 		 'origin location
 		 'element (make-music 'SequentialMusic
@@ -713,37 +772,52 @@ Syntax:
   (define-music-function (parser location arg1 arg2 ...) (arg1-type? arg2-type? ...)
     ...function body...)
 "
-  `(ly:make-music-function (list ,@signature)
-			   (lambda (,@args)
-			     ,@body)))
+(if (and (pair? body) (pair? (car body)) (eqv? '_i (caar body)))
+      ;; When the music function definition contains a i10n doc string,
+      ;; (_i "doc string"), keep the literal string only
+      (let ((docstring (cadar body))
+	    (body (cdr body)))
+	`(ly:make-music-function (list ,@signature)
+				 (lambda (,@args)
+				   ,docstring
+				   ,@body)))
+      `(ly:make-music-function (list ,@signature)
+			       (lambda (,@args)
+				 ,@body))))
 
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (define-public (cue-substitute quote-music)
-  "Must happen after quote-substitute."
-  
+  "Must happen after @code{quote-substitute}."
+
   (if (vector? (ly:music-property quote-music 'quoted-events))
       (let* ((dir (ly:music-property quote-music 'quoted-voice-direction))
+	     (clef (ly:music-property quote-music 'quoted-music-clef))
 	     (main-voice (if (eq? 1 dir) 1 0))
 	     (cue-voice (if (eq? 1 dir) 0 1))
 	     (main-music (ly:music-property quote-music 'element))
 	     (return-value quote-music))
 
 	(if (or (eq? 1 dir) (eq? -1 dir))
-	    
+
 	    ;; if we have stem dirs, change both quoted and main music
 	    ;; to have opposite stems.
 	    (begin
 	      (set! return-value
-
 		    ;; cannot context-spec Quote-music, since context
 		    ;; for the quotes is determined in the iterator.
 		    (make-sequential-music
 		     (list
+		      (if (null? clef)
+		          (make-music 'Music)
+		          (make-cue-clef-set clef))
 		      (context-spec-music (make-voice-props-set cue-voice) 'CueVoice "cue")
 		      quote-music
-		      (context-spec-music (make-voice-props-revert)  'CueVoice "cue"))))
+		      (context-spec-music (make-voice-props-revert) 'CueVoice "cue")
+		      (if (null? clef)
+		          (make-music 'Music)
+		          (make-cue-clef-unset)))))
 	      (set! main-music
 		    (make-sequential-music
 		     (list
@@ -757,11 +831,10 @@ Syntax:
 
 (define-public ((quote-substitute quote-tab) music)
   (let* ((quoted-name (ly:music-property music 'quoted-music-name))
-	 (quoted-vector (if (string? quoted-name)
-			    (hash-ref quote-tab quoted-name #f)
-			    #f)))
+	 (quoted-vector (and (string? quoted-name)
+			     (hash-ref quote-tab quoted-name #f))))
+
 
-    
     (if (string? quoted-name)
 	(if (vector? quoted-vector)
 	    (begin
@@ -788,7 +861,7 @@ Syntax:
     (if (and (ly:music? m)
 	     (eq? (ly:music-property m 'error-found) #t))
 	(set! found #t)))
-  
+
   (for-each signal (ly:music-property music 'elements))
   (signal (ly:music-property music 'element))
 
@@ -801,41 +874,86 @@ Syntax:
 	(ly:music-length music))
   music)
 
-(define (skip-to-last music parser)
-
+(define-public (make-duration-of-length moment)
+ "Make duration of the given @code{moment} length."
+ (ly:make-duration 0 0
+  (ly:moment-main-numerator moment)
+  (ly:moment-main-denominator moment)))
+
+(define (make-skipped moment bool)
+ "Depending on BOOL, set or unset skipTypesetting,
+then make SkipMusic of the given MOMENT length, and
+then revert skipTypesetting."
+ (make-sequential-music
+  (list
+   (context-spec-music (make-property-set 'skipTypesetting bool)
+    'Score)
+   (make-music 'SkipMusic 'duration
+    (make-duration-of-length moment))
+   (context-spec-music (make-property-set 'skipTypesetting (not bool))
+    'Score))))
+
+(define (skip-as-needed music parser)
   "Replace MUSIC by
-
-<< { \\set skipTypesetting = ##t
-     LENGTHOF(\\showLastLength)
-     \\set skipTypesetting = ##t  }
-    MUSIC >>
-
-if appropriate.
- "
+ << {  \\set skipTypesetting = ##f
+ LENGTHOF(\\showFirstLength)
+ \\set skipTypesetting = ##t
+ LENGTHOF(\\showLastLength) }
+ MUSIC >>
+ if appropriate.
+
+ When only showFirstLength is set,
+ the 'length property of the music is
+ overridden to speed up compiling."
   (let*
-      ((show-last  (ly:parser-lookup parser 'showLastLength)))
-    
-    (if (ly:music? show-last)
-	(let*
-	    ((orig-length (ly:music-length music))
-	     (skip-length (ly:moment-sub orig-length (ly:music-length show-last))))
-
-	  (make-simultaneous-music
-	   (list
-	    (make-sequential-music
-	     (list
-	      (context-spec-music (make-property-set 'skipTypesetting #t)
-				  'Score)
-	      (make-music 'SkipMusic 'duration
-			  (ly:make-duration
-			   0 0
-			   (ly:moment-main-numerator skip-length)
-			   (ly:moment-main-denominator skip-length)))
-	      (context-spec-music (make-property-set 'skipTypesetting #f)
-				  'Score)))
-	    music)))
-	music)))
-    
+      ((show-last (ly:parser-lookup parser 'showLastLength))
+       (show-first (ly:parser-lookup parser 'showFirstLength))
+       (show-last-length (and (ly:music? show-last)
+			      (ly:music-length show-last)))
+       (show-first-length (and (ly:music? show-first)
+			       (ly:music-length show-first)))
+       (orig-length (ly:music-length music)))
+
+    ;;FIXME: if using either showFirst- or showLastLength,
+    ;; make sure that skipBars is not set.
+
+    (cond
+
+     ;; both properties may be set.
+     ((and show-first-length show-last-length)
+      (let
+          ((skip-length (ly:moment-sub orig-length show-last-length)))
+        (make-simultaneous-music
+         (list
+          (make-sequential-music
+           (list
+            (make-skipped skip-length #t)
+            ;; let's draw a separator between the beginning and the end
+            (context-spec-music (make-property-set 'whichBar "||")
+                                'Timing)))
+          (make-skipped show-first-length #f)
+          music))))
+
+     ;; we may only want to print the last length
+     (show-last-length
+      (let
+          ((skip-length (ly:moment-sub orig-length show-last-length)))
+        (make-simultaneous-music
+         (list
+          (make-skipped skip-length #t)
+          music))))
+
+     ;; we may only want to print the beginning; in this case
+     ;; only the first length will be processed (much faster).
+     (show-first-length
+      ;; the first length must not exceed the original length.
+      (if (ly:moment<? show-first-length orig-length)
+          (set! (ly:music-property music 'length)
+                show-first-length))
+      music)
+
+     (else music))))
+
 
 (define-public toplevel-music-functions
   (list
@@ -845,32 +963,243 @@ if appropriate.
    (lambda (music parser)
 
      (music-map (quote-substitute (ly:parser-lookup parser 'musicQuotes))  music))
-   
+
    ;; switch-on-debugging
    (lambda (x parser) (music-map cue-substitute x))
- 
+
    (lambda (x parser)
-     (skip-to-last x parser)
+     (skip-as-needed x parser)
    )))
 
+;;;;;;;;;;
+;;; general purpose music functions
+
+(define (shift-octave pitch octave-shift)
+  (_i "Add @var{octave-shift} to the octave of @var{pitch}.")
+  (ly:make-pitch
+     (+ (ly:pitch-octave pitch) octave-shift)
+     (ly:pitch-notename pitch)
+     (ly:pitch-alteration pitch)))
+
 
 ;;;;;;;;;;;;;;;;;
 ;; lyrics
 
-(define (apply-durations lyric-music durations) 
+(define (apply-durations lyric-music durations)
   (define (apply-duration music)
     (if (and (not (equal? (ly:music-length music) ZERO-MOMENT))
 	     (ly:duration?  (ly:music-property music 'duration)))
 	(begin
 	  (set! (ly:music-property music 'duration) (car durations))
 	  (set! durations (cdr durations)))))
-  
+
   (music-map apply-duration lyric-music))
 
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; accidentals
 
+(define (recent-enough? bar-number alteration-def laziness)
+  (or (number? alteration-def)
+      (equal? laziness #t)
+      (<= bar-number (+ (cadr alteration-def) laziness))))
+
+(define (accidental-invalid? alteration-def)
+  "Checks an alteration entry for being invalid.
+
+Non-key alterations are invalidated when tying into the next bar or
+when there is a clef change, since neither repetition nor cancellation
+can be omitted when the same note occurs again.
+
+Returns @code{#f} or the reason for the invalidation, a symbol."
+  (let* ((def (if (pair? alteration-def)
+		  (car alteration-def)
+		  alteration-def)))
+    (and (symbol? def) def)))
+
+(define (extract-alteration alteration-def)
+  (cond ((number? alteration-def)
+	 alteration-def)
+	((pair? alteration-def)
+	 (car alteration-def))
+	(else 0)))
+
+(define (check-pitch-against-signature context pitch barnum laziness octaveness)
+  "Checks the need for an accidental and a @q{restore} accidental against
+@code{localKeySignature}.  The @var{laziness} is the number of measures
+for which reminder accidentals are used (i.e., if @var{laziness} is zero,
+only cancel accidentals in the same measure; if @var{laziness} is three,
+we cancel accidentals up to three measures after they first appear.
+@var{octaveness} is either @code{'same-octave} or @code{'any-octave} and
+specifies whether accidentals should be canceled in different octaves."
+  (let* ((ignore-octave (cond ((equal? octaveness 'any-octave) #t)
+			      ((equal? octaveness 'same-octave) #f)
+			      (else
+			       (ly:warning (_ "Unknown octaveness type: ~S ") octaveness)
+			       (ly:warning (_ "Defaulting to 'any-octave."))
+			       #t)))
+	 (key-sig (ly:context-property context 'keySignature))
+	 (local-key-sig (ly:context-property context 'localKeySignature))
+	 (notename (ly:pitch-notename pitch))
+	 (octave (ly:pitch-octave pitch))
+	 (pitch-handle (cons octave notename))
+	 (need-restore #f)
+	 (need-accidental #f)
+	 (previous-alteration #f)
+	 (from-other-octaves #f)
+	 (from-same-octave (assoc-get pitch-handle local-key-sig))
+	 (from-key-sig (or (assoc-get notename local-key-sig)
+
+    ;; If no key signature match is found from localKeySignature, we may have a custom
+    ;; type with octave-specific entries of the form ((octave . pitch) alteration)
+    ;; instead of (pitch . alteration).  Since this type cannot coexist with entries in
+    ;; localKeySignature, try extracting from keySignature instead.
+			   (assoc-get pitch-handle key-sig))))
+
+    ;; loop through localKeySignature to search for a notename match from other octaves
+    (let loop ((l local-key-sig))
+      (if (pair? l)
+	  (let ((entry (car l)))
+	    (if (and (pair? (car entry))
+		     (= (cdar entry) notename))
+		(set! from-other-octaves (cdr entry))
+		(loop (cdr l))))))
+
+    ;; find previous alteration-def for comparison with pitch
+    (cond
+     ;; from same octave?
+     ((and (not ignore-octave)
+	   from-same-octave
+	   (recent-enough? barnum from-same-octave laziness))
+      (set! previous-alteration from-same-octave))
+
+     ;; from any octave?
+     ((and ignore-octave
+	   from-other-octaves
+	   (recent-enough? barnum from-other-octaves laziness))
+      (set! previous-alteration from-other-octaves))
+
+     ;; not recent enough, extract from key signature/local key signature
+     (from-key-sig
+      (set! previous-alteration from-key-sig)))
+
+    (if (accidental-invalid? previous-alteration)
+	(set! need-accidental #t)
+
+	(let* ((prev-alt (extract-alteration previous-alteration))
+	       (this-alt (ly:pitch-alteration pitch)))
+
+	  (if (not (= this-alt prev-alt))
+	      (begin
+		(set! need-accidental #t)
+		(if (and (not (= this-alt 0))
+			 (or (< (abs this-alt) (abs prev-alt))
+			     (< (* prev-alt this-alt) 0)))
+		    (set! need-restore #t))))))
+
+    (cons need-restore need-accidental)))
+
+(define-public ((make-accidental-rule octaveness laziness) context pitch barnum measurepos)
+  "Create an accidental rule that makes its decision based on the octave of
+the note and a laziness value.
+
+@var{octaveness} is either @code{'same-octave} or @code{'any-octave} and
+defines whether the rule should respond to accidental changes in other
+octaves than the current.  @code{'same-octave} is the normal way to typeset
+accidentals -- an accidental is made if the alteration is different from the
+last active pitch in the same octave.  @code{'any-octave} looks at the last
+active pitch in any octave.
+
+@var{laziness} states over how many bars an accidental should be remembered.
+@code{0}@tie{}is the default -- accidental lasts over 0@tie{}bar lines, that
+is, to the end of current measure.  A positive integer means that the
+accidental lasts over that many bar lines.  @code{-1} is `forget
+immediately', that is, only look at key signature.  @code{#t} is `forever'."
+
+  (check-pitch-against-signature context pitch barnum laziness octaveness))
+
+(define (key-entry-notename entry)
+  "Return the pitch of an entry in localKeySignature.  The entry is either of the form
+  '(notename . alter) or '((octave . notename) . (alter barnum . measurepos))."
+  (if (number? (car entry))
+      (car entry)
+      (cdar entry)))
+
+(define (key-entry-octave entry)
+  "Return the octave of an entry in localKeySignature (or #f if the entry does not have
+  an octave)."
+  (and (pair? (car entry)) (caar entry)))
+
+(define (key-entry-bar-number entry)
+  "Return the bar number of an entry in localKeySignature (or #f if the entry does not
+  have a bar number)."
+  (and (pair? (car entry)) (caddr entry)))
+
+(define (key-entry-measure-position entry)
+  "Return the measure position of an entry in localKeySignature (or #f if the entry does
+  not have a measure position)."
+  (and (pair? (car entry)) (cdddr entry)))
+
+(define (key-entry-alteration entry)
+  "Return the alteration of an entry in localKeySignature.
+
+For convenience, returns @code{0} if entry is @code{#f}."
+  (if entry
+      (if (number? (car entry))
+	  (cdr entry)
+	  (cadr entry))
+      0))
+
+(define-public (find-pitch-entry keysig pitch accept-global accept-local)
+  "Return the first entry in @var{keysig} that matches @var{pitch}.
+@var{accept-global} states whether key signature entries should be included.
+@var{accept-local} states whether local accidentals should be included.
+If no matching entry is found, @var{#f} is returned."
+  (and (pair? keysig)
+       (let* ((entry (car keysig))
+	      (entryoct (key-entry-octave entry))
+	      (entrynn (key-entry-notename entry))
+	      (oct (ly:pitch-octave pitch))
+	      (nn (ly:pitch-notename pitch)))
+	 (if (and (equal? nn entrynn)
+		  (or (and accept-global (not entryoct))
+		      (and accept-local (equal? oct entryoct))))
+	     entry
+	     (find-pitch-entry (cdr keysig) pitch accept-global accept-local)))))
+
+(define-public (neo-modern-accidental-rule context pitch barnum measurepos)
+  "An accidental rule that typesets an accidental if it differs from the
+key signature @emph{and} does not directly follow a note on the same
+staff line.  This rule should not be used alone because it does neither
+look at bar lines nor different accidentals at the same note name."
+  (let* ((keysig (ly:context-property context 'localKeySignature))
+	 (entry (find-pitch-entry keysig pitch #t #t)))
+    (if (not entry)
+	(cons #f #f)
+	(let* ((global-entry (find-pitch-entry keysig pitch #t #f))
+	       (key-acc (key-entry-alteration global-entry))
+	       (acc (ly:pitch-alteration pitch))
+	       (entrymp (key-entry-measure-position entry))
+	       (entrybn (key-entry-bar-number entry)))
+	  (cons #f (not (or (equal? acc key-acc)
+			    (and (equal? entrybn barnum) (equal? entrymp measurepos)))))))))
+
+(define-public (teaching-accidental-rule context pitch barnum measurepos)
+  "An accidental rule that typesets a cautionary accidental if it is
+included in the key signature @emph{and} does not directly follow a note
+on the same staff line."
+  (let* ((keysig (ly:context-property context 'localKeySignature))
+	 (entry (find-pitch-entry keysig pitch #t #t)))
+    (if (not entry)
+	(cons #f #f)
+	(let* ((global-entry (find-pitch-entry keysig pitch #f #f))
+	       (key-acc (key-entry-alteration global-entry))
+	       (acc (ly:pitch-alteration pitch))
+	       (entrymp (key-entry-measure-position entry))
+	       (entrybn (key-entry-bar-number entry)))
+	  (cons #f (not (or (equal? acc key-acc)
+			    (and (equal? entrybn barnum) (equal? entrymp measurepos)))))))))
+
 (define-public (set-accidentals-properties extra-natural
 					   auto-accs auto-cauts
 					   context)
@@ -884,9 +1213,10 @@ if appropriate.
    context))
 
 (define-public (set-accidental-style style . rest)
-  "Set accidental style to STYLE. Optionally takes a context argument,
-e.g. 'Staff or 'Voice. The context defaults to Voice, except for piano styles, which
-use GrandStaff as a context. "
+  "Set accidental style to @var{style}.  Optionally take a context
+argument, e.g. @code{'Staff} or @code{'Voice}.  The context defaults
+to @code{Staff}, except for piano styles, which use @code{GrandStaff}
+as a context."
   (let ((context (if (pair? rest)
 		     (car rest) 'Staff))
 	(pcontext (if (pair? rest)
@@ -895,80 +1225,192 @@ use GrandStaff as a context. "
      (cond
       ;; accidentals as they were common in the 18th century.
       ((equal? style 'default)
-       (set-accidentals-properties #t '(Staff (same-octave . 0))
-				   '() context))
+       (set-accidentals-properties #t
+				   `(Staff ,(make-accidental-rule 'same-octave 0))
+				   '()
+				   context))
       ;; accidentals from one voice do NOT get cancelled in other voices
       ((equal? style 'voice)
-       (set-accidentals-properties #t '(Voice (same-octave . 0))
-				   '() context))
+       (set-accidentals-properties #t
+				   `(Voice ,(make-accidental-rule 'same-octave 0))
+				   '()
+				   context))
       ;; accidentals as suggested by Kurt Stone, Music Notation in the 20th century.
       ;; This includes all the default accidentals, but accidentals also needs cancelling
       ;; in other octaves and in the next measure.
       ((equal? style 'modern)
-       (set-accidentals-properties #f '(Staff (same-octave . 0) (any-octave . 0) (same-octave . 1))
-				   '()	context))
+       (set-accidentals-properties #f
+				   `(Staff ,(make-accidental-rule 'same-octave 0)
+					   ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1))
+				   '()
+				   context))
       ;; the accidentals that Stone adds to the old standard as cautionaries
       ((equal? style 'modern-cautionary)
-       (set-accidentals-properties #f '(Staff (same-octave . 0))
-				   '(Staff (any-octave . 0) (same-octave . 1))
+       (set-accidentals-properties #f
+				   `(Staff ,(make-accidental-rule 'same-octave 0))
+				   `(Staff ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1))
+				   context))
+      ;; same as modern, but accidentals different from the key signature are always
+      ;; typeset - unless they directly follow a note of the same pitch.
+      ((equal? style 'neo-modern)
+       (set-accidentals-properties #f
+				   `(Staff ,(make-accidental-rule 'same-octave 0)
+					   ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+				           ,neo-modern-accidental-rule)
+				   '()
+				   context))
+      ((equal? style 'neo-modern-cautionary)
+       (set-accidentals-properties #f
+				   `(Staff ,(make-accidental-rule 'same-octave 0))
+				   `(Staff ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+				           ,neo-modern-accidental-rule)
+				   context))
+      ((equal? style 'neo-modern-voice)
+       (set-accidentals-properties #f
+				   `(Voice ,(make-accidental-rule 'same-octave 0)
+					   ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+					   ,neo-modern-accidental-rule
+				     Staff ,(make-accidental-rule 'same-octave 0)
+					   ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+				      ,neo-modern-accidental-rule)
+				   '()
+				   context))
+      ((equal? style 'neo-modern-voice-cautionary)
+       (set-accidentals-properties #f
+				   `(Voice ,(make-accidental-rule 'same-octave 0))
+				   `(Voice ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+					   ,neo-modern-accidental-rule
+				     Staff ,(make-accidental-rule 'same-octave 0)
+					   ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+					   ,neo-modern-accidental-rule)
+				   context))
+      ;; Accidentals as they were common in dodecaphonic music with no tonality.
+      ;; Each note gets one accidental.
+      ((equal? style 'dodecaphonic)
+       (set-accidentals-properties #f
+				   `(Staff ,(lambda (c p bn mp) '(#f . #t)))
+				   '()
 				   context))
       ;; Multivoice accidentals to be read both by musicians playing one voice
       ;; and musicians playing all voices.
       ;; Accidentals are typeset for each voice, but they ARE cancelled across voices.
       ((equal? style 'modern-voice)
        (set-accidentals-properties  #f
-				    '(Voice (same-octave . 0) (any-octave . 0) (same-octave . 1)
-					    Staff (same-octave . 0) (any-octave . 0) (same-octave . 1))
+				    `(Voice ,(make-accidental-rule 'same-octave 0)
+					    ,(make-accidental-rule 'any-octave 0)
+					    ,(make-accidental-rule 'same-octave 1)
+				      Staff ,(make-accidental-rule 'same-octave 0)
+					    ,(make-accidental-rule 'any-octave 0)
+					    ,(make-accidental-rule 'same-octave 1))
 				    '()
 				    context))
       ;; same as modernVoiceAccidental eccept that all special accidentals are typeset
       ;; as cautionaries
       ((equal? style 'modern-voice-cautionary)
        (set-accidentals-properties #f
-				   '(Voice (same-octave . 0))
-				   '(Voice (any-octave . 0) (same-octave . 1)
-					   Staff (same-octave . 0) (any-octave . 0) (same-octave . 1))
+				   `(Voice ,(make-accidental-rule 'same-octave 0))
+				   `(Voice ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+				     Staff ,(make-accidental-rule 'same-octave 0)
+				           ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1))
 				   context))
       ;; stone's suggestions for accidentals on grand staff.
       ;; Accidentals are cancelled across the staves in the same grand staff as well
       ((equal? style 'piano)
        (set-accidentals-properties #f
-				   '(Staff (same-octave . 0)
-					   (any-octave . 0) (same-octave . 1)
-					   GrandStaff (any-octave . 0) (same-octave . 1))
+				   `(Staff ,(make-accidental-rule 'same-octave 0)
+					   ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+				     GrandStaff
+				           ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1))
 				   '()
 				   pcontext))
       ((equal? style 'piano-cautionary)
        (set-accidentals-properties #f
-				   '(Staff (same-octave . 0))
-				   '(Staff (any-octave . 0) (same-octave . 1)
-					   GrandStaff (any-octave . 0) (same-octave . 1))
+				   `(Staff ,(make-accidental-rule 'same-octave 0))
+				   `(Staff ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1)
+				     GrandStaff
+				           ,(make-accidental-rule 'any-octave 0)
+					   ,(make-accidental-rule 'same-octave 1))
 				   pcontext))
+
+      ;; same as modern, but cautionary accidentals are printed for all sharp or flat
+      ;; tones specified by the key signature.
+       ((equal? style 'teaching)
+       (set-accidentals-properties #f
+				    `(Staff ,(make-accidental-rule 'same-octave 0))
+				    `(Staff ,(make-accidental-rule 'same-octave 1)
+				           ,teaching-accidental-rule)
+				   context))
+
       ;; do not set localKeySignature when a note alterated differently from
       ;; localKeySignature is found.
       ;; Causes accidentals to be printed at every note instead of
       ;; remembered for the duration of a measure.
-      ;; accidentals not being remembered, causing accidentals always to be typeset relative to the time signature
+      ;; accidentals not being remembered, causing accidentals always to
+      ;; be typeset relative to the time signature
       ((equal? style 'forget)
        (set-accidentals-properties '()
-				   '(Staff (same-octave . -1))
-				   '() context))
+				   `(Staff ,(make-accidental-rule 'same-octave -1))
+				   '()
+				   context))
       ;; Do not reset the key at the start of a measure.  Accidentals will be
       ;; printed only once and are in effect until overridden, possibly many
       ;; measures later.
       ((equal? style 'no-reset)
        (set-accidentals-properties '()
-				   '(Staff (same-octave . #t))
+				   `(Staff ,(make-accidental-rule 'same-octave #t))
 				   '()
 				   context))
       (else
-       (ly:warning (_ "unknown accidental style: ~S" style))
+       (ly:warning (_ "unknown accidental style: ~S") style)
        (make-sequential-music '()))))))
 
+(define-public (invalidate-alterations context)
+  "Invalidate alterations in @var{context}.
+
+Elements of @code{'localKeySignature} corresponding to local
+alterations of the key signature have the form
+@code{'((octave . notename) . (alter barnum . measurepos))}.
+Replace them with a version where @code{alter} is set to @code{'clef}
+to force a repetition of accidentals.
+
+Entries that conform with the current key signature are not invalidated."
+  (let* ((keysig (ly:context-property context 'keySignature)))
+    (set! (ly:context-property context 'localKeySignature)
+	  (map-in-order
+	   (lambda (entry)
+	     (let* ((localalt (key-entry-alteration entry))
+		    (localoct (key-entry-octave entry)))
+	       (if (or (accidental-invalid? localalt)
+		       (not localoct)
+		       (= localalt
+			  (key-entry-alteration
+			   (find-pitch-entry
+			    keysig
+			    (ly:make-pitch localoct
+					   (key-entry-notename entry)
+					   0)
+			    #t #t))))
+		   entry
+		   (cons (car entry) (cons 'clef (cddr entry))))))
+	   (ly:context-property context 'localKeySignature)))))
+  		    
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (define-public (skip-of-length mus)
-  "Create a skip of exactly the same length as MUS."
+  "Create a skip of exactly the same length as @var{mus}."
   (let* ((skip
 	  (make-music
 	   'SkipEvent
@@ -977,8 +1419,8 @@ use GrandStaff as a context. "
     (make-event-chord (list (ly:music-compress skip (ly:music-length mus))))))
 
 (define-public (mmrest-of-length mus)
-  "Create a mmrest of exactly the same length as MUS."
-  
+  "Create a multi-measure rest of exactly the same length as @var{mus}."
+
   (let* ((skip
 	  (make-multi-measure-rest
 	   (ly:make-duration 0 0) '())))
@@ -986,12 +1428,48 @@ use GrandStaff as a context. "
     skip))
 
 (define-public (pitch-of-note event-chord)
-
-  (let*
-      ((evs (filter (lambda (x) (memq 'note-event (ly:music-property x 'types)))
-		    (ly:music-property event-chord 'elements))))
-
-    (if (pair? evs)
-	(ly:music-property (car evs) 'pitch)
-	#f)))
-       
+  (let ((evs (filter (lambda (x)
+		       (music-has-type x 'note-event))
+		     (ly:music-property event-chord 'elements))))
+
+    (and (pair? evs)
+	 (ly:music-property (car evs) 'pitch))))
+
+(define-public (duration-of-note event-chord)
+  (let ((evs (filter (lambda (x)
+		       (music-has-type x 'rhythmic-event))
+		     (ly:music-property event-chord 'elements))))
+
+    (and (pair? evs)
+	 (ly:music-property (car evs) 'duration))))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(define-public (extract-named-music music music-name)
+  "Return a flat list of all music named @var{music-name} from @var{music}."
+   (let ((extracted-list
+          (if (ly:music? music)
+              (if (eq? (ly:music-property music 'name) music-name)
+                  (list music)
+                  (let ((elt (ly:music-property music 'element))
+                        (elts (ly:music-property music 'elements)))
+                    (if (ly:music? elt)
+                        (extract-named-music elt music-name)
+                        (if (null? elts)
+                            '()
+                            (map (lambda(x)
+                                    (extract-named-music x music-name ))
+                             elts)))))
+              '())))
+     (flatten-list extracted-list)))
+
+(define-public (event-chord-notes event-chord)
+  "Return a list of all notes from @var{event-chord}."
+  (filter
+    (lambda (m) (eq? 'NoteEvent (ly:music-property m 'name)))
+    (ly:music-property event-chord 'elements)))
+
+(define-public (event-chord-pitches event-chord)
+  "Return a list of all pitches from @var{event-chord}."
+  (map (lambda (x) (ly:music-property x 'pitch))
+       (event-chord-notes event-chord)))