X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=scm%2Flily-library.scm;h=05875b2da2ec5915d7d4c99ae5c89489e9a13986;hb=HEAD;hp=8176db1d7b66ee31ec1ebd4f881709e662cc8545;hpb=0387f04497978e37b335a8b99eec905499d6ad0f;p=lilypond.git

diff --git a/scm/lily-library.scm b/scm/lily-library.scm
index 8176db1d7b..05875b2da2 100644
--- a/scm/lily-library.scm
+++ b/scm/lily-library.scm
@@ -1,10 +1,28 @@
+;;;; This file is part of LilyPond, the GNU music typesetter.
 ;;;;
-;;;; lily-library.scm -- utilities
-;;;;
-;;;;  source file of the GNU LilyPond music typesetter
-;;;; 
-;;;; (c) 1998--2008 Jan Nieuwenhuizen <janneke@gnu.org>
+;;;; Copyright (C) 1998--2015 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/>.
+
+;; for take, drop, take-while, list-index, and find-tail:
+(use-modules (srfi srfi-1))
+
+;; for define-safe-public when byte-compiling using Guile V2
+(use-modules (scm safe-utility-defs))
+
+(use-modules (ice-9 pretty-print))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; constants.
@@ -19,17 +37,6 @@
 (define-public DOWN -1)
 (define-public CENTER 0)
 
-(define-safe-public DOUBLE-FLAT-QTS -4)
-(define-safe-public THREE-Q-FLAT-QTS -3)
-(define-safe-public FLAT-QTS -2)
-(define-safe-public SEMI-FLAT-QTS -1)
-(define-safe-public NATURAL-QTS 0)
-(define-safe-public SEMI-SHARP-QTS 1)
-(define-safe-public SHARP-QTS 2)
-(define-safe-public THREE-Q-SHARP-QTS 3)
-(define-safe-public DOUBLE-SHARP-QTS 4)
-(define-safe-public SEMI-TONE-QTS 2)
-
 (define-safe-public DOUBLE-FLAT  -1)
 (define-safe-public THREE-Q-FLAT -3/4)
 (define-safe-public FLAT -1/2)
@@ -41,14 +48,80 @@
 (define-safe-public DOUBLE-SHARP 1)
 (define-safe-public SEMI-TONE 1/2)
 
+(define-safe-public INFINITY-INT 1000000)
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; moments
 
-(define-public ZERO-MOMENT (ly:make-moment 0 1)) 
+(define-public ZERO-MOMENT (ly:make-moment 0 1))
 
 (define-public (moment-min a b)
   (if (ly:moment<? a b) a b))
 
+(define-public (moment<=? a b)
+  (or (equal? a b)
+      (ly:moment<? a b)))
+
+(define-public (fraction->moment fraction)
+  (if (null? fraction)
+      ZERO-MOMENT
+      (ly:make-moment (car fraction) (cdr fraction))))
+
+(define-public (moment->fraction moment)
+  (cons (ly:moment-main-numerator moment)
+        (ly:moment-main-denominator moment)))
+
+(define-public (seconds->moment s context)
+  "Return a moment equivalent to s seconds at the current tempo."
+  (ly:moment-mul (ly:context-property context 'tempoWholesPerMinute)
+                 (ly:make-moment (/ s 60))))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; durations
+
+(define-public (duration-log-factor lognum)
+  "Given a logarithmic duration number, return the length of the duration,
+as a number of whole notes."
+  (or (and (exact? lognum) (integer? lognum))
+      (scm-error 'wrong-type-arg "duration-log-factor" "Not an integer: ~S" (list lognum) #f))
+  (if (<= lognum 0)
+      (ash 1 (- lognum))
+      (/ (ash 1 lognum))))
+
+(define-public (duration-dot-factor dotcount)
+  "Given a count of the dots used to extend a musical duration, return
+the numeric factor by which they increase the duration."
+  (or (and (exact? dotcount) (integer? dotcount) (>= dotcount 0))
+      (scm-error 'wrong-type-arg "duration-dot-factor" "Not a count: ~S" (list dotcount) #f))
+  (- 2 (/ (ash 1 dotcount))))
+
+(define-public (duration-length dur)
+  "Return the overall length of a duration, as a number of whole
+notes.  (Not to be confused with ly:duration-length, which returns a
+less-useful moment object.)"
+  (ly:moment-main (ly:duration-length dur)))
+
+(define-public (duration-visual dur)
+  "Given a duration object, return the visual part of the duration (base
+note length and dot count), in the form of a duration object with
+non-visual scale factor 1."
+  (ly:make-duration (ly:duration-log dur) (ly:duration-dot-count dur) 1))
+
+(define-public (duration-visual-length dur)
+  "Given a duration object, return the length of the visual part of the
+duration (base note length and dot count), as a number of whole notes."
+  (duration-length (duration-visual dur)))
+
+(define-public (unity-if-multimeasure context dur)
+  "Given a context and a duration, return @code{1} if the duration is
+longer than the @code{measureLength} in that context, and @code{#f} otherwise.
+This supports historic use of @code{Completion_heads_engraver} to split
+@code{c1*3} into three whole notes."
+  (if (ly:moment<? (ly:context-property context 'measureLength)
+                   (ly:duration-length dur))
+    1
+    #f))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; arithmetic
 (define-public (average x . lst)
@@ -56,169 +129,347 @@
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; parser <-> output hooks.
-		
-(define-public (collect-bookpart-for-book parser book-part)
-  "Toplevel book-part handler"
+
+(define-public (collect-bookpart-for-book book-part)
+  "Toplevel book-part handler."
   (define (add-bookpart book-part)
-    (ly:parser-define!
-       parser 'toplevel-bookparts
-       (cons book-part (ly:parser-lookup parser 'toplevel-bookparts))))
+    (ly:parser-define! 'toplevel-bookparts
+     (cons book-part (ly:parser-lookup 'toplevel-bookparts))))
   ;; If toplevel scores have been found before this \bookpart,
   ;; add them first to a dedicated bookpart
-  (if (pair? (ly:parser-lookup parser 'toplevel-scores))
+  (if (pair? (ly:parser-lookup 'toplevel-scores))
       (begin
-	(add-bookpart (ly:make-book-part
-		       (ly:parser-lookup parser 'toplevel-scores)))
-	(ly:parser-define! parser 'toplevel-scores (list))))
+        (add-bookpart (ly:make-book-part
+                       (ly:parser-lookup 'toplevel-scores)))
+        (ly:parser-define! 'toplevel-scores (list))))
   (add-bookpart book-part))
 
-(define-public (collect-scores-for-book parser score)
-  (ly:parser-define!
-   parser 'toplevel-scores
-   (cons score (ly:parser-lookup parser 'toplevel-scores))))
+(define-public (collect-scores-for-book score)
+  (ly:parser-define! 'toplevel-scores
+   (cons score (ly:parser-lookup 'toplevel-scores))))
 
-(define-public (collect-music-aux score-handler parser music)
+(define-public (collect-music-aux score-handler music)
   (define (music-property symbol)
-    (let ((value (ly:music-property music symbol)))
-      (if (not (null? value))
-	  value
-	  #f)))
+    (ly:music-property music symbol #f))
   (cond ((music-property 'page-marker)
-	 ;; a page marker: set page break/turn permissions or label
-	 (begin
-	   (let ((label (music-property 'page-label)))
-	     (if (symbol? label)
-		 (score-handler (ly:make-page-label-marker label))))
-	   (for-each (lambda (symbol)
-		       (let ((permission (music-property symbol)))
-			 (if (symbol? permission)
-			     (score-handler
-			      (ly:make-page-permission-marker symbol
-							      (if (eqv? 'forbid permission)
-								  '()
-								  permission))))))
-		     (list 'line-break-permission 'page-break-permission
-			   'page-turn-permission))))
-	((not (music-property 'void))
-	 ;; a regular music expression: make a score with this music
-	 ;; void music is discarded
-	 (score-handler (scorify-music music parser)))))
-
-(define-public (collect-music-for-book parser music)
-  "Top-level music handler"
+         ;; a page marker: set page break/turn permissions or label
+         (let ((label (music-property 'page-label)))
+           (if (symbol? label)
+               (score-handler (ly:make-page-label-marker label))))
+         (for-each (lambda (symbol)
+                     (let ((permission (music-property symbol)))
+                       (if (symbol? permission)
+                           (score-handler
+                            (ly:make-page-permission-marker symbol
+                                                            (if (eq? 'forbid permission)
+                                                                '()
+                                                                permission))))))
+                   '(line-break-permission page-break-permission
+                                           page-turn-permission)))
+        ((not (music-property 'void))
+         ;; a regular music expression: make a score with this music
+         ;; void music is discarded
+         (score-handler (scorify-music music)))))
+
+(define-public (collect-music-for-book music)
+  "Top-level music handler."
   (collect-music-aux (lambda (score)
-		       (collect-scores-for-book parser score))
-                     parser
-		     music))
+                       (collect-scores-for-book score))
+                     music))
 
-(define-public (collect-book-music-for-book parser book music)
-  "Book music handler"
+(define-public (collect-book-music-for-book book music)
+  "Book music handler."
   (collect-music-aux (lambda (score)
-		       (ly:book-add-score! book score))
-                     parser
-		     music))
-
-(define-public (scorify-music music parser)
-  "Preprocess MUSIC."
-  
-  (for-each (lambda (func)
-	      (set! music (func music parser)))
-	    toplevel-music-functions)
-
-  (ly:make-score music))
-
-(define (print-book-with parser book process-procedure)
-  (let*
-      ((paper (ly:parser-lookup parser '$defaultpaper))
-       (layout (ly:parser-lookup parser '$defaultlayout))
-       (count (ly:parser-lookup parser 'output-count))
-       (base (ly:parser-output-name parser))
-       (output-suffix (ly:parser-lookup parser 'output-suffix)) )
-
+                       (ly:book-add-score! book score))
+                     music))
+
+(define-public (scorify-music music)
+  "Preprocess @var{music}."
+  (ly:make-score
+   (fold (lambda (f m) (f m))
+         music
+         toplevel-music-functions)))
+
+(define (get-current-filename book)
+  "return any suffix value for output filename allowing for settings by
+calls to bookOutputName function"
+  (or (paper-variable book 'output-filename)
+      (ly:parser-output-name)))
+
+(define (get-current-suffix book)
+  "return any suffix value for output filename allowing for settings by calls to
+bookoutput function"
+  (let ((book-output-suffix (paper-variable book 'output-suffix)))
+    (if (not (string? book-output-suffix))
+        (ly:parser-lookup 'output-suffix)
+        book-output-suffix)))
+
+(define-public current-outfile-name #f)  ; for use by regression tests
+
+(define (get-outfile-name book)
+  "return current filename for generating backend output files"
+  ;; user can now override the base file name, so we have to use
+  ;; the file-name concatenated with any potential output-suffix value
+  ;; as the key to out internal a-list
+  (let* ((base-name (get-current-filename book))
+         (output-suffix (get-current-suffix book))
+         (alist-key (format #f "~a~a" base-name output-suffix))
+         (counter-alist (ly:parser-lookup 'counter-alist))
+         (output-count (assoc-get alist-key counter-alist 0))
+         (result base-name))
+    ;; Allow all ASCII alphanumerics, including accents
     (if (string? output-suffix)
-	(set! base (format "~a-~a" base (string-regexp-substitute
-					   "[^a-zA-Z0-9-]" "_" output-suffix))))
-
-    ;; must be careful: output-count is under user control.
-    (if (not (integer? count))
-	(set! count 0))
-
-    (if (> count 0)
-	(set! base (format #f "~a-~a" base count)))
-    (ly:parser-define! parser 'output-count (1+ count))
-    (process-procedure book paper layout base)
-    ))
-
-(define-public (print-book-with-defaults parser book)
-  (print-book-with parser book ly:book-process))
+        (set! result
+              (format #f "~a-~a"
+                      result
+                      (string-regexp-substitute
+                       "[^-[:alnum:]]"
+                       "_"
+                       output-suffix))))
+
+    ;; assoc-get call will always have returned a number
+    (if (> output-count 0)
+        (set! result (format #f "~a-~a" result output-count)))
+
+    (ly:parser-define! 'counter-alist
+     (assoc-set! counter-alist alist-key (1+ output-count)))
+    (set! current-outfile-name result)
+    result))
+
+(define (print-book-with book process-procedure)
+  (let* ((paper (ly:parser-lookup '$defaultpaper))
+         (layout (ly:parser-lookup '$defaultlayout))
+         (outfile-name (get-outfile-name book)))
+    (process-procedure book paper layout outfile-name)))
+
+(define-public (print-book-with-defaults book)
+  (print-book-with book ly:book-process))
+
+(define-public (print-book-with-defaults-as-systems book)
+  (print-book-with book ly:book-process-to-systems))
+
+;; Add a score to the current bookpart, book or toplevel
+(define-public (add-score score)
+  (cond
+   ((ly:parser-lookup '$current-bookpart)
+    ((ly:parser-lookup 'bookpart-score-handler)
+     (ly:parser-lookup '$current-bookpart) score))
+   ((ly:parser-lookup '$current-book)
+    ((ly:parser-lookup 'book-score-handler)
+     (ly:parser-lookup '$current-book) score))
+   (else
+    ((ly:parser-lookup 'toplevel-score-handler) score))))
+
+(define-public paper-variable
+  (let
+      ((get-papers
+        (lambda (book)
+          (append (if (and book (ly:output-def? (ly:book-paper book)))
+                      (list (ly:book-paper book))
+                      '())
+                  (ly:parser-lookup '$papers)
+                  (list (ly:parser-lookup '$defaultpaper))))))
+    (make-procedure-with-setter
+     (lambda (book symbol)
+       (any (lambda (p) (ly:output-def-lookup p symbol #f))
+            (get-papers book)))
+     (lambda (book symbol value)
+       (ly:output-def-set-variable!
+        (car (get-papers book))
+        symbol value)))))
+
+(define-public (add-text text)
+  (add-score (list text)))
+
+(define-public (add-music music)
+  (collect-music-aux (lambda (score)
+                       (add-score score))
+                     music))
+
+(define-public (context-mod-from-music music)
+  (let ((warn #t) (mods (ly:make-context-mod)))
+    (let loop ((m music))
+      (if (music-is-of-type? m 'layout-instruction-event)
+          (let ((symbol (ly:music-property m 'symbol)))
+            (ly:add-context-mod
+             mods
+             (case (ly:music-property m 'name)
+               ((PropertySet)
+                (list 'assign
+                      symbol
+                      (ly:music-property m 'value)))
+               ((PropertyUnset)
+                (list 'unset symbol))
+               ((OverrideProperty)
+                (cons* 'push
+                       symbol
+                       (ly:music-property m 'grob-value)
+                       (cond
+                        ((ly:music-property m 'grob-property #f) => list)
+                        (else
+                         (ly:music-property m 'grob-property-path)))))
+               ((RevertProperty)
+                (cons* 'pop
+                       symbol
+                       (cond
+                        ((ly:music-property m 'grob-property #f) => list)
+                        (else
+                         (ly:music-property m 'grob-property-path))))))))
+          (case (ly:music-property m 'name)
+            ((ApplyContext)
+             (ly:add-context-mod mods
+                                 (list 'apply
+                                       (ly:music-property m 'procedure))))
+            ((ContextSpeccedMusic)
+             (loop (ly:music-property m 'element)))
+            (else
+             (let ((callback (ly:music-property m 'elements-callback)))
+               (if (procedure? callback)
+                   (for-each loop (callback m))
+                   (if (and warn (ly:duration? (ly:music-property m 'duration)))
+                       (begin
+                         (ly:music-warning
+                          music
+                          (_ "Music unsuitable for context-mod"))
+                         (set! warn #f)))))))))
+    mods))
+
+(define-public (context-defs-from-music output-def music)
+  (let ((warn #t))
+    (let loop ((m music) (mods #f))
+      ;; The parser turns all sets, overrides etc into something
+      ;; wrapped in ContextSpeccedMusic.  If we ever get a set,
+      ;; override etc that is not wrapped in ContextSpeccedMusic, the
+      ;; user has created it in Scheme himself without providing the
+      ;; required wrapping.  In that case, using #f in the place of a
+      ;; context modification results in a reasonably recognizable
+      ;; error.
+      (if (music-is-of-type? m 'layout-instruction-event)
+          (ly:add-context-mod
+           mods
+           (case (ly:music-property m 'name)
+             ((PropertySet)
+              (list 'assign
+                    (ly:music-property m 'symbol)
+                    (ly:music-property m 'value)))
+             ((PropertyUnset)
+              (list 'unset
+                    (ly:music-property m 'symbol)))
+             ((OverrideProperty)
+              (cons* 'push
+                     (ly:music-property m 'symbol)
+                     (ly:music-property m 'grob-value)
+                     (cond
+                      ((ly:music-property m 'grob-property #f) => list)
+                      (else
+                       (ly:music-property m 'grob-property-path)))))
+             ((RevertProperty)
+              (cons* 'pop
+                     (ly:music-property m 'symbol)
+                     (cond
+                      ((ly:music-property m 'grob-property #f) => list)
+                      (else
+                       (ly:music-property m 'grob-property-path)))))))
+          (case (ly:music-property m 'name)
+            ((ApplyContext)
+             (ly:add-context-mod mods
+                                 (list 'apply
+                                       (ly:music-property m 'procedure))))
+            ((ContextSpeccedMusic)
+             ;; Use let* here to let defs catch up with modifications
+             ;; to the context defs made in the recursion
+             (let* ((mods (loop (ly:music-property m 'element)
+                                (ly:make-context-mod)))
+                    (defs (ly:output-find-context-def
+                           output-def (ly:music-property m 'context-type))))
+               (if (null? defs)
+                   (ly:music-warning
+                    music
+                    (ly:format (_ "Cannot find context-def \\~a")
+                               (ly:music-property m 'context-type)))
+                   (for-each
+                    (lambda (entry)
+                      (ly:output-def-set-variable!
+                       output-def (car entry)
+                       (ly:context-def-modify (cdr entry) mods)))
+                    defs))))
+            (else
+             (let ((callback (ly:music-property m 'elements-callback)))
+               (if (procedure? callback)
+                   (fold loop mods (callback m))
+                   (if (and warn (ly:duration? (ly:music-property m 'duration)))
+                       (begin
+                         (ly:music-warning
+                          music
+                          (_ "Music unsuitable for output-def"))
+                         (set! warn #f))))))))
+      mods)))
 
-(define-public (print-book-with-defaults-as-systems parser book)
-  (print-book-with parser book ly:book-process-to-systems))
 
 ;;;;;;;;;;;;;;;;
 ;; alist
 
 (define-public assoc-get ly:assoc-get)
 
+(define-public chain-assoc-get ly:chain-assoc-get)
+
 (define-public (uniqued-alist alist acc)
   (if (null? alist) acc
       (if (assoc (caar alist) acc)
-	  (uniqued-alist (cdr alist) acc)
-	  (uniqued-alist (cdr alist) (cons (car alist) acc)))))
+          (uniqued-alist (cdr alist) acc)
+          (uniqued-alist (cdr alist) (cons (car alist) acc)))))
 
 (define-public (alist<? x y)
   (string<? (symbol->string (car x))
-	    (symbol->string (car y))))
-
-(define-public (chain-assoc-get x alist-list . default)
-  "Return ALIST entry for X. Return DEFAULT (optional, else #f) if not
-found."
-
-  (define (helper x alist-list default)
-    (if (null? alist-list)
-	default
-	(let* ((handle (assoc x (car alist-list))))
-	  (if (pair? handle)
-	      (cdr handle)
-	      (helper x (cdr alist-list) default)))))
-
-  (helper x alist-list
-	  (if (pair? default) (car default) #f)))
+            (symbol->string (car y))))
 
 (define (map-alist-vals func list)
-  "map FUNC over the vals of  LIST, leaving the keys."
+  "map FUNC over the vals of LIST, leaving the keys."
   (if (null?  list)
       '()
       (cons (cons  (caar list) (func (cdar list)))
-	    (map-alist-vals func (cdr list)))))
+            (map-alist-vals func (cdr list)))))
 
 (define (map-alist-keys func list)
-  "map FUNC over the keys of an alist LIST, leaving the vals. "
+  "map FUNC over the keys of an alist LIST, leaving the vals."
   (if (null?  list)
       '()
       (cons (cons (func (caar list)) (cdar list))
-	    (map-alist-keys func (cdr list)))))
+            (map-alist-keys func (cdr list)))))
 
 (define-public (first-member members lst)
-  "Return first successful MEMBER of member from MEMBERS in LST."
-  (if (null? members)
-      #f
-      (let ((m (member (car members) lst)))
-	(if m m (first-member (cdr members) lst)))))
+  "Return first successful member (of member) from @var{members} in
+@var{lst}."
+  (any (lambda (m) (member m lst)) members))
 
 (define-public (first-assoc keys lst)
-  "Return first successful ASSOC of key from KEYS in LST."
-  (if (null? keys)
-      #f
-      (let ((k (assoc (car keys) lst)))
-	(if k k (first-assoc (cdr keys) lst)))))
+  "Return first successful assoc of key from @var{keys} in @var{lst}."
+  (any (lambda (k) (assoc k lst)) keys))
 
 (define-public (flatten-alist alist)
   (if (null? alist)
       '()
       (cons (caar alist)
-	    (cons (cdar alist)
-		  (flatten-alist (cdr alist))))))
+            (cons (cdar alist)
+                  (flatten-alist (cdr alist))))))
+
+(define-public (map-selected-alist-keys function keys alist)
+  "Return @var{alist} with @var{function} applied to all of the values
+in list @var{keys}.
+
+For example:
+@example
+@code{guile> (map-selected-alist-keys - '(a b) '((a . 1) (b . -2) (c . 3) (d . 4)))}
+@code{((a . -1) (b . 2) (c . 3) (d . 4)}
+@end example"
+  (define (map-selected-alist-keys-helper key alist)
+    (map
+     (lambda (pair)
+       (if (equal? key (car pair))
+           (cons key (function (cdr pair)))
+           pair))
+     alist))
+  (fold map-selected-alist-keys-helper alist keys))
 
 ;;;;;;;;;;;;;;;;
 ;; vector
@@ -233,260 +484,311 @@ found."
 ;; hash
 
 (define-public (hash-table->alist t)
-  (hash-fold (lambda (k v acc) (acons  k v  acc))
-	     '() t))
+  (hash-fold acons '() t))
 
-;; todo: code dup with C++. 
+;; todo: code dup with C++.
 (define-safe-public (alist->hash-table lst)
   "Convert alist to table"
   (let ((m (make-hash-table (length lst))))
-    (map (lambda (k-v) (hashq-set! m (car k-v) (cdr k-v))) lst)
+    (for-each (lambda (k-v) (hashq-set! m (car k-v) (cdr k-v))) lst)
     m))
 
 ;;;;;;;;;;;;;;;;
 ;; list
 
 (define (functional-or . rest)
-  (if (pair? rest)
-      (or (car rest)
-	   (apply functional-and (cdr rest)))
-      #f))
+  (any identity rest))
 
 (define (functional-and . rest)
-  (if (pair? rest)
-      (and (car rest)
-	   (apply functional-and (cdr rest)))
-      #t))
+  (every identity rest))
 
 (define (split-list lst n)
   "Split LST in N equal sized parts"
-  
+
   (define (helper todo acc-vector k)
     (if (null? todo)
-	acc-vector
-	(begin
-	  (if (< k 0)
-	      (set! k (+ n k)))
-	    
-	  (vector-set! acc-vector k (cons (car todo) (vector-ref acc-vector k)))
-	  (helper (cdr todo) acc-vector (1- k)))))
+        acc-vector
+        (begin
+          (if (< k 0)
+              (set! k (+ n k)))
+
+          (vector-set! acc-vector k (cons (car todo) (vector-ref acc-vector k)))
+          (helper (cdr todo) acc-vector (1- k)))))
 
   (helper lst (make-vector n '()) (1- n)))
 
 (define (list-element-index lst x)
-  (define (helper todo k)
-    (cond
-     ((null? todo) #f)
-     ((equal? (car todo) x) k)
-     (else
-      (helper (cdr todo) (1+ k)))))
-
-  (helper lst 0))
+  (list-index (lambda (m) (equal? m x)) lst))
 
 (define-public (count-list lst)
-  "Given lst (E1 E2 .. ) return ((E1 . 1) (E2 . 2) ... )  "
-
-  (define (helper l acc count)
-    (if (pair? l)
-	(helper (cdr l) (cons (cons (car l) count) acc) (1+ count))
-	acc))
+  "Given @var{lst} as @code{(E1 E2 .. )}, return
+@code{((E1 . 1) (E2 . 2) ... )}."
+  (map cons lst (iota (length lst) 1)))
 
-
-  (reverse (helper lst '() 1)))
-  
 (define-public (list-join lst intermediate)
-  "put INTERMEDIATE  between all elts of LST."
+  "Put @var{intermediate} between all elts of @var{lst}."
 
   (fold-right
    (lambda (elem prev)
-	    (if (pair? prev)
-		(cons  elem (cons intermediate prev))
-		(list elem)))
-	  '() lst))
-
-(define-public (filtered-map proc lst)
-  (filter
-   (lambda (x) x)
-   (map proc lst)))
+     (if (pair? prev)
+         (cons  elem (cons intermediate prev))
+         (list elem)))
+   '() lst))
 
+(define-public filtered-map filter-map)
 
-(define (flatten-list lst)
-  "Unnest LST" 
-  (if (null? lst)
-      '()
-      (if (pair? (car lst))
-	  (append (flatten-list (car lst)) (flatten-list  (cdr lst)))
-	  (cons (car lst) (flatten-list (cdr lst))))))
+(define-public (flatten-list x)
+  "Unnest list."
+  (let loop ((x x) (tail '()))
+    (cond ((list? x) (fold-right loop tail x))
+          ((not (pair? x)) (cons x tail))
+          (else (loop (car x) (loop (cdr x) tail))))))
 
 (define (list-minus a b)
   "Return list of elements in A that are not in B."
   (lset-difference eq? a b))
 
 (define-public (uniq-list lst)
-  "Uniq LST, assuming that it is sorted. Uses equal? for comparisons."
+  "Uniq @var{lst}, assuming that it is sorted.  Uses @code{equal?}
+for comparisons."
 
-  (reverse! 
+  (reverse!
    (fold (lambda (x acc)
-	   (if (null? acc)
-	       (list x)
-	       (if (equal? x (car acc))
-		   acc
-		   (cons x acc))))
-	 '() lst) '()))
-
-(define (split-at-predicate predicate lst)
- "Split LST = (a_1 a_2 ... a_k b_1 ... b_k)
-  into L1 = (a_1 ... a_k ) and L2 =(b_1 .. b_k) 
-  Such that (PREDICATE a_i a_{i+1}) and not (PREDICATE a_k b_1).
-  L1 is copied, L2 not.
-
-  (split-at-predicate (lambda (x y) (= (- y x) 2)) '(1 3 5 9 11) (cons '() '()))"
- 
- ;; " Emacs is broken
-
- (define (inner-split predicate lst acc)
-   (cond
-    ((null? lst) acc)
-    ((null? (cdr lst))
-     (set-car! acc (cons (car lst) (car acc)))
-     acc)
-    ((predicate (car lst) (cadr lst))
-     (set-car! acc (cons (car lst) (car acc)))
-     (inner-split predicate (cdr lst) acc))
-    (else
-     (set-car! acc (cons (car lst) (car acc)))
-     (set-cdr! acc (cdr lst))
-     acc)))
- 
- (let* ((c (cons '() '())))
-   (inner-split predicate lst  c)
-   (set-car! c (reverse! (car c)))
-   c))
-
-(define-public (split-list-by-separator lst sep?)
-   "(display (split-list-by-separator '(a b c / d e f / g) (lambda (x) (equal? x '/))))
-   =>
-   ((a b c) (d e f) (g))
-  "
-   ;; " Emacs is broken
-   (define (split-one sep?  lst acc)
-     "Split off the first parts before separator and return both parts."
-     (if (null? lst)
-	 (cons acc '())
-	 (if (sep? (car lst))
-	     (cons acc (cdr lst))
-	     (split-one sep? (cdr lst) (cons (car lst) acc)))))
-   
-   (if (null? lst)
-       '()
-       (let* ((c (split-one sep? lst '())))
-	 (cons (reverse! (car c) '()) (split-list-by-separator (cdr c) sep?)))))
+           (if (null? acc)
+               (list x)
+               (if (equal? x (car acc))
+                   acc
+                   (cons x acc))))
+         '() lst) '()))
+
+(define (split-at-predicate pred lst)
+  "Split LST into two lists at the first element that returns #f for
+  (PRED previous_element element).  Return the two parts as a pair.
+  Example: (split-at-predicate < '(1 2 3 2 1)) ==> ((1 2 3) . (2 1))"
+  (let ((i (and (pair? lst)
+                (list-index (lambda (x y) (not (pred x y)))
+                            lst
+                            (cdr lst)))))
+    (if i
+        (call-with-values
+            (lambda () (split-at lst (1+ i)))
+          cons)
+        (list lst))))
+
+(define-public (split-list-by-separator lst pred)
+  "Split @var{lst} at each element that satisfies @var{pred}, and return
+the parts (with the separators removed) as a list of lists.  For example,
+executing @samp{(split-list-by-separator '(a 0 b c 1 d) number?)} returns
+@samp{((a) (b c) (d))}."
+  (call-with-values (lambda () (break pred lst))
+    (lambda (head tail)
+      (cons head
+            (if (null? tail)
+                tail
+                (split-list-by-separator (cdr tail) pred))))))
 
 (define-public (offset-add a b)
   (cons (+ (car a) (car b))
-	(+ (cdr a) (cdr b)))) 
+        (+ (cdr a) (cdr b))))
 
 (define-public (offset-flip-y o)
   (cons (car o) (- (cdr o))))
 
 (define-public (offset-scale o scale)
   (cons (* (car o) scale)
-	(* (cdr o) scale)))
+        (* (cdr o) scale)))
 
 (define-public (ly:list->offsets accum coords)
   (if (null? coords)
       accum
       (cons (cons (car coords) (cadr coords))
-	    (ly:list->offsets accum (cddr coords)))))
+            (ly:list->offsets accum (cddr coords)))))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; numbers
-
-(if (not (defined? 'nan?)) ;; guile 1.6 compat
-    (define-public (nan? x) (not (or (< 0.0 x)
-				     (> 0.0 x)
-				     (= 0.0 x)))))
+;; intervals
 
-(if (not (defined? 'inf?))
-    (define-public (inf? x) (= (/ 1.0 x) 0.0)))
+(define-public empty-interval '(+inf.0 . -inf.0))
 
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; intervals
+(define-public (symmetric-interval expr)
+  (cons (- expr) expr))
 
 (define-public (interval-length x)
-  "Length of the number-pair X, when an interval"
+  "Length of the number-pair @var{x}, if an interval."
   (max 0 (- (cdr x) (car x))))
 
-(define-public interval-start car)
 (define-public (ordered-cons a b)
   (cons (min a b)
-	(max a b)))
-
-(define-public interval-end cdr)
+        (max a b)))
 
 (define-public (interval-bound interval dir)
   ((if (= dir RIGHT) cdr car) interval))
 
 (define-public (interval-index interval dir)
-  "Interpolate INTERVAL between between left (DIR=-1) and right (DIR=+1)"
-  
+  "Interpolate @var{interval} between between left (@var{dir}=-1) and
+right (@var{dir}=+1)."
+
   (* (+  (interval-start interval) (interval-end interval)
-	 (* dir (- (interval-end interval) (interval-start interval))))
+         (* dir (- (interval-end interval) (interval-start interval))))
      0.5))
 
 (define-public (interval-center x)
-  "Center the number-pair X, when an interval"
+  "Center the number-pair @var{x}, if an interval."
   (if (interval-empty? x)
       0.0
       (/ (+ (car x) (cdr x)) 2)))
 
 (define-public interval-start car)
+
 (define-public interval-end cdr)
-(define-public (interval-translate iv amount)
-  (cons (+ amount (car iv))
-	(+ amount (cdr iv))))
 
 (define (other-axis a)
   (remainder (+ a 1) 2))
 
-(define-public (interval-widen iv amount)
-   (cons (- (car iv) amount)
-         (+ (cdr iv) amount)))
+(define-public (interval-scale iv factor)
+  (cons (* (car iv) factor)
+        (* (cdr iv) factor)))
 
+(define-public (interval-widen iv amount)
+  (cons (- (car iv) amount)
+        (+ (cdr iv) amount)))
 
 (define-public (interval-empty? iv)
-   (> (car iv) (cdr iv)))
+  (> (car iv) (cdr iv)))
 
 (define-public (interval-union i1 i2)
-   (cons (min (car i1) (car i2))
-	 (max (cdr i1) (cdr i2))))
+  (cons
+   (min (car i1) (car i2))
+   (max (cdr i1) (cdr i2))))
+
+(define-public (interval-intersection i1 i2)
+  (cons
+   (max (car i1) (car i2))
+   (min (cdr i1) (cdr i2))))
 
 (define-public (interval-sane? i)
   (not (or  (nan? (car i))
-	    (inf? (car i))
-	    (nan? (cdr i))
-	    (inf? (cdr i))
-	    (> (car i) (cdr i)))))
+            (inf? (car i))
+            (nan? (cdr i))
+            (inf? (cdr i))
+            (> (car i) (cdr i)))))
+
+(define-public (add-point interval p)
+  (cons (min (interval-start interval) p)
+        (max (interval-end interval) p)))
+
+(define-public (reverse-interval iv)
+  (cons (cdr iv) (car iv)))
 
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; coordinates
+
+(define coord-x car)
+(define coord-y cdr)
+
+(define (coord-operation operator operand coordinate)
+  (if (pair? operand)
+      (cons (operator (coord-x operand) (coord-x coordinate))
+            (operator (coord-y operand) (coord-y coordinate)))
+      (cons (operator operand (coord-x coordinate))
+            (operator operand (coord-y coordinate)))))
+
+(define (coord-apply function coordinate)
+  (if (pair? function)
+      (cons
+       ((coord-x function) (coord-x coordinate))
+       ((coord-y function) (coord-y coordinate)))
+      (cons
+       (function (coord-x coordinate))
+       (function (coord-y coordinate)))))
+
+(define-public (coord-translate coordinate amount)
+  (coord-operation + amount coordinate))
+
+(define-public (coord-scale coordinate amount)
+  (coord-operation * amount coordinate))
+
+(define-public (coord-rotate coordinate angle-in-radians)
+  (coord-rotated coordinate (/ angle-in-radians PI-OVER-180)))
+
+(define-public (coord-rotated coordinate direction)
+  ;; Same, in degrees or with a given direction
+  (let ((dir (ly:directed direction)))
+    (cons (- (* (car dir) (car coordinate))
+             (* (cdr dir) (cdr coordinate)))
+          (+ (* (car dir) (cdr coordinate))
+             (* (cdr dir) (car coordinate))))))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; trig
+
+(define-public PI (* 4 (atan 1)))
+
+(define-public TWO-PI (* 2 PI))
+
+(define-public PI-OVER-TWO (/ PI 2))
+
+(define-public THREE-PI-OVER-TWO (* 3 PI-OVER-TWO))
+
+(define-public (cyclic-base-value value cycle)
+  "Take @var{value} and modulo-maps it between 0 and base @var{cycle}."
+  (cond ((< value 0)
+         (cyclic-base-value (+ value cycle) cycle))
+        ((>= value cycle)
+         (cyclic-base-value (- value cycle) cycle))
+        (else value)))
+
+(define-public (angle-0-2pi angle)
+  "Take @var{angle} (in radians) and maps it between 0 and 2pi."
+  (cyclic-base-value angle TWO-PI))
+
+(define-public (angle-0-360 angle)
+  "Take @var{angle} (in degrees) and maps it between 0 and 360 degrees."
+  (cyclic-base-value angle 360.0))
+
+(define-public PI-OVER-180  (/ PI 180))
+
+(define-public (degrees->radians angle-degrees)
+  "Convert the given angle from degrees to radians."
+  (* angle-degrees PI-OVER-180))
+
+(define-public (ellipse-radius x-radius y-radius angle)
+  (/
+   (* x-radius y-radius)
+   (sqrt
+    (+ (* (expt y-radius 2)
+          (* (cos angle) (cos angle)))
+       (* (expt x-radius 2)
+          (* (sin angle) (sin angle)))))))
+
+(define-public (polar->rectangular radius angle-in-degrees)
+  "Return polar coordinates (@var{radius}, @var{angle-in-degrees})
+as rectangular coordinates @code{(x-length . y-length)}."
+  (ly:directed angle-in-degrees radius))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; string
 
 (define-public (string-endswith s suffix)
   (equal? suffix (substring s
-			    (max 0 (- (string-length s) (string-length suffix)))
-			    (string-length s))))
-	     
+                            (max 0 (- (string-length s) (string-length suffix)))
+                            (string-length s))))
+
 (define-public (string-startswith s prefix)
   (equal? prefix (substring s 0 (min (string-length s) (string-length prefix)))))
-	     
+
+(define-public (remove-whitespace strg)
+"Remove characters satisfying @code{char-whitespace?} from string @var{strg}"
+  (if (guile-v2)
+      (string-delete char-whitespace? strg)
+      (string-delete strg char-whitespace?)))
+
 (define-public (string-encode-integer i)
   (cond
    ((= i  0) "o")
    ((< i 0)   (string-append "n" (string-encode-integer (- i))))
    (else (string-append
-	  (make-string 1 (integer->char (+ 65 (modulo i 26))))
-	  (string-encode-integer (quotient i 26))))))
+          (make-string 1 (integer->char (+ 65 (modulo i 26))))
+          (string-encode-integer (quotient i 26))))))
 
 (define (number->octal-string x)
   (let* ((n (inexact->exact x))
@@ -503,27 +805,28 @@ found."
 
 (define-public (ly:number-pair->string c)
   (string-append (ly:number->string (car c)) " "
-		 (ly:number->string (cdr c))))
+                 (ly:number->string (cdr c))))
 
 (define-public (dir-basename file . rest)
-  "Strip suffixes in REST, but leave directory component for FILE."
+  "Strip suffixes in @var{rest}, but leave directory component for
+@var{file}."
   (define (inverse-basename x y) (basename y x))
   (simple-format #f "~a/~a" (dirname file)
-		 (fold inverse-basename file rest)))
+                 (fold inverse-basename file rest)))
 
 (define-public (write-me message x)
-  "Return X.  Display MESSAGE and write X.  Handy for debugging,
-possibly turned off."
+  "Return @var{x}.  Display @var{message} and write @var{x}.
+Handy for debugging, possibly turned off."
   (display message) (write x) (newline) x)
 ;;  x)
 
 (define-public (stderr string . rest)
-  (apply format (cons (current-error-port) (cons string rest)))
+  (apply format (current-error-port) string rest)
   (force-output (current-error-port)))
 
 (define-public (debugf string . rest)
   (if #f
-      (apply stderr (cons string rest))))
+      (apply stderr string rest)))
 
 (define (index-cell cell dir)
   (if (equal? dir 1)
@@ -535,15 +838,15 @@ possibly turned off."
   (cons (f (car x)) (f (cdr x))))
 
 (define-public (list-insert-separator lst between)
-  "Create new list, inserting BETWEEN between elements of LIST"
+  "Create new list, inserting @var{between} between elements of @var{lst}."
   (define (conc x y )
     (if (eq? y #f)
-	(list x)
-	(cons x  (cons between y))))
+        (list x)
+        (cons x  (cons between y))))
   (fold-right conc #f lst))
 
 (define-public (string-regexp-substitute a b str)
-  (regexp-substitute/global #f a str 'pre b 'post)) 
+  (regexp-substitute/global #f a str 'pre b 'post))
 
 (define (regexp-split str regex)
   (define matches '())
@@ -551,9 +854,9 @@ possibly turned off."
   (define (notice match)
 
     (set! matches (cons (substring (match:string match)
-				   end-of-prev-match
-				   (match:start match))
-			matches))
+                                   end-of-prev-match
+                                   (match:start match))
+                        matches))
     (set! end-of-prev-match (match:end match)))
 
   (regexp-substitute/global #f regex str notice 'post)
@@ -563,34 +866,146 @@ possibly turned off."
        matches
        (cons (substring str end-of-prev-match (string-length str)) matches)))
 
-   (reverse matches))
+  (reverse matches))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; numbering styles
+
+(define-public (number-format number-type num . custom-format)
+  "Print NUM accordingly to the requested NUMBER-TYPE.
+Choices include @code{roman-lower} (by default),
+@code{roman-upper}, @code{arabic} and @code{custom}.
+In the latter case, CUSTOM-FORMAT must be supplied
+and will be applied to NUM."
+ (cond
+   ((equal? number-type 'roman-lower)
+    (fancy-format #f "~(~@r~)" num))
+   ((equal? number-type 'roman-upper)
+    (fancy-format #f "~@r" num))
+   ((equal? number-type 'arabic)
+    (fancy-format #f "~d" num))
+   ((equal? number-type 'custom)
+    (fancy-format #f (car custom-format) num))
+   (else (fancy-format #f "~(~@r~)" num))))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; lilypond version
+
+(define (lexicographic-list-compare? op a b)
+  "Lexicographically compare two lists @var{a} and @var{b} using
+   the operator @var{op}. The types of the list elements have to
+   be comparable with @var{op}. If the lists are of different length
+   the trailing elements of the longer list are ignored."
+  (let* ((ca (car a))
+         (iseql (op ca ca)))
+    (let loop ((ca ca) (cb (car b)) (a (cdr a)) (b (cdr b)))
+      (let ((axb (op ca cb)))
+        (if (and (pair? a) (pair? b)
+                 (eq? axb iseql (op cb ca)))
+            (loop (car a) (car b) (cdr a) (cdr b))
+            axb)))))
+
+(define (ly:version? op ver)
+  "Using the operator @var{op} compare the currently executed LilyPond
+   version with a given version @var{ver} which is passed as a list of 
+   numbers."
+  (lexicographic-list-compare? op (ly:version) ver))
 
 ;;;;;;;;;;;;;;;;
-; other
+;; other
+
 (define (sign x)
   (if (= x 0)
       0
       (if (< x 0) -1 1)))
 
+(define-public (binary-search start end getter target-val)
+  (_i "Find the index between @var{start} and @var{end} (an integer)
+which produces the closest match to @var{target-val} if
+applied to function @var{getter}.")
+  (if (<= end start)
+      start
+      (let* ((compare (quotient (+ start end) 2))
+             (get-val (getter compare)))
+        (cond
+         ((< target-val get-val)
+          (set! end (1- compare)))
+         ((< get-val target-val)
+          (set! start (1+ compare))))
+        (binary-search start end getter target-val))))
 
 (define-public (car< a b)
   (< (car a) (car b)))
 
+(define-public (car<= a b)
+  (<= (car a) (car b)))
+
 (define-public (symbol<? lst r)
   (string<? (symbol->string lst) (symbol->string r)))
 
 (define-public (symbol-key<? lst r)
   (string<? (symbol->string (car lst)) (symbol->string (car r))))
 
-;;
-;; don't confuse users with #<procedure .. > syntax. 
-;; 
+(define-public (eval-carefully symbol module . default)
+  "Check whether all symbols in expr @var{symbol} are reachable
+in module @var{module}.  In that case evaluate, otherwise
+print a warning and set an optional @var{default}."
+  (let* ((unavailable? (lambda (sym)
+                         (not (module-defined? module sym))))
+         (sym-unavailable
+          (filter
+           unavailable?
+           (filter symbol? (flatten-list symbol)))))
+    (if (null? sym-unavailable)
+        (eval symbol module)
+        (let* ((def (and (pair? default) (car default))))
+          (ly:programming-error
+           "cannot evaluate ~S in module ~S, setting to ~S"
+           (object->string symbol)
+           (object->string module)
+           (object->string def))
+          def))))
+
+(define (self-evaluating? x)
+  (or (number? x) (string? x) (procedure? x) (boolean? x)))
+
+(define (ly-type? x)
+  (any (lambda (p) ((car p) x)) lilypond-exported-predicates))
+
+(define-public (pretty-printable? val)
+  (and (not (self-evaluating? val))
+       (not (symbol? val))
+       (not (hash-table? val))
+       (not (ly-type? val))))
+
 (define-public (scm->string val)
-  (if (and (procedure? val) (symbol? (procedure-name val)))
-      (symbol->string (procedure-name val))
-      (string-append
-       (if (self-evaluating? val) "" "'")
-       (call-with-output-string (lambda (port) (display val port))))))
+  (let* ((quote-style (if (string? val)
+                        'double
+                        (if (or (null? val) ; (ly-type? '()) => #t
+                                (and (not (self-evaluating? val))
+                                     (not (vector? val))
+                                     (not (hash-table? val))
+                                     (not (ly-type? val))))
+                          'single
+                          'none)))
+         ; don't confuse users with #<procedure ...> syntax
+         (str (if (and (procedure? val)
+                       (symbol? (procedure-name val)))
+                (symbol->string (procedure-name val))
+                (call-with-output-string
+                  (if (pretty-printable? val)
+                    ; property values in PDF hit margin after 64 columns
+                    (lambda (port)
+                      (pretty-print val port #:width (case quote-style
+                                                       ((single) 63)
+                                                       (else 64))))
+                    (lambda (port) (display val port)))))))
+    (case quote-style
+      ((single) (string-append
+                  "'"
+                  (string-regexp-substitute "\n " "\n  " str)))
+      ((double) (string-append "\"" str "\""))
+      (else str))))
 
 (define-public (!= lst r)
   (not (= lst r)))
@@ -606,39 +1021,30 @@ possibly turned off."
 
 ;;; FONT may be font smob, or pango font string...
 (define-public (font-name-style font)
-      ;; FIXME: ughr, (ly:font-name) sometimes also has Style appended.
+  (if (string? font)
+      (string-downcase font)
       (let* ((font-name (ly:font-name font))
-	     (full-name (if font-name font-name (ly:font-file-name font)))
-	     (name-style (string-split full-name #\-)))
-	;; FIXME: ughr, barf: feta-alphabet is actually emmentaler
-	(if (string-prefix? "feta-alphabet" full-name)
-	    (list "emmentaler"
-		  (substring  full-name (string-length "feta-alphabet")))
-	    (if (not (null? (cdr name-style)))
-	    name-style
-	    (append name-style '("Regular"))))))
+             (full-name (if font-name font-name (ly:font-file-name font))))
+        (string-downcase full-name))))
 
 (define-public (modified-font-metric-font-scaling font)
   (let* ((designsize (ly:font-design-size font))
-	 (magnification (* (ly:font-magnification font)))
-	 (scaling (* magnification designsize)))
+         (magnification (* (ly:font-magnification font)))
+         (scaling (* magnification designsize)))
     (debugf "scaling:~S\n" scaling)
     (debugf "magnification:~S\n" magnification)
     (debugf "design:~S\n" designsize)
     scaling))
 
 (define-public (version-not-seen-message input-file-name)
-  (ly:message
-   "~a:0: ~a: ~a" 
-    input-file-name
-    (_ "warning: ")
-    (format #f
-	    (_ "no \\version statement found, please add~afor future compatibility")
-	    (format #f "\n\n\\version ~s\n\n" (lilypond-version)))))
-
-(define-public (old-relative-not-used-message input-file-name)
-  (ly:message
-   "~a:0: ~a: ~a" 
-    input-file-name
-    (_ "warning: ")
-    (_ "old relative compatibility not used")))
+  (ly:warning-located
+   (ly:format "~a:1" input-file-name)
+   (_ "no \\version statement found, please add~afor future compatibility")
+   (format #f "\n\n\\version ~s\n\n" (lilypond-version))))
+
+(define-public (output-module? module)
+  "Returns @code{#t} if @var{module} belongs to an output module
+usually carrying context definitions (@code{\\midi} or
+@code{\\layout})."
+  (or (module-ref module 'is-midi #f)
+      (module-ref module 'is-layout #f)))