Improve doc-string for stringTunings

[lilypond.git] / scm / ly-syntax-constructors.scm

diff --git a/scm/ly-syntax-constructors.scm b/scm/ly-syntax-constructors.scm
index 98365930fefa16e2a1e8c4751b8196774206b290..c34f5c9dd1dc81864acc7d2f143e7ba0d1e5dc7a 100644 (file)
--- a/scm/ly-syntax-constructors.scm
+++ b/scm/ly-syntax-constructors.scm
@@ -17,7 +17,8 @@
 
 ;; TODO: use separate module for syntax
 ;; constructors. Also create wrapper around the constructor?
-(define define-ly-syntax define-public)
+(defmacro define-ly-syntax (args . body)
+  `(define-public ,args ,(cons 'begin body)))
 
 ;; A ly-syntax constructor takes two extra parameters, parser and
 ;; location. These are mainly used for reporting errors and
@@ -25,22 +26,21 @@
 ;; location arg to set the origin of the returned music object; this
 ;; behaviour is usually desired
 (defmacro define-ly-syntax-loc (args . body)
-  (primitive-eval `(define-ly-syntax ,args
-                    (let ((m ,(cons 'begin body)))
-                      (set! (ly:music-property m 'origin) ,(third args))
-                      m))))
-
+  `(define-public ,args
+     (let ((m ,(cons 'begin body)))
+       (set! (ly:music-property m 'origin) ,(third args))
+       m)))
 ;; Like define-ly-syntax-loc, but adds parser and location
 ;; parameters. Useful for simple constructors that don't need to
 ;; report errors.
 (defmacro define-ly-syntax-simple (args . body)
-  (primitive-eval `(define-ly-syntax ,(cons* (car args) 
-                                            'parser
-                                            'location 
-                                            (cdr args))
-                    (let ((m ,(cons 'begin body)))
-                      (set! (ly:music-property m 'origin) location)
-                      m))))
+  `(define-public ,(cons* (car args)
+                         'parser
+                         'location
+                         (cdr args))
+     (let ((m ,(cons 'begin body)))
+       (set! (ly:music-property m 'origin) location)
+       m)))
 
 ;; Music function: Apply function and check return value.
 (define-ly-syntax-loc (music-function parser loc fun args)
@@ -90,19 +90,23 @@
              'element (ly:music-transpose music pitch)))
 
 (define-ly-syntax-simple (tempo text duration tempo)
-  (let ((props (list
-                 (make-property-set 'tempoWholesPerMinute
-                       (ly:moment-mul (ly:make-moment tempo 1)
-                                      (ly:duration-length duration)))
-                 (make-property-set 'tempoUnitDuration duration)
-                 (make-property-set 'tempoUnitCount tempo))))
-    (set! props (cons 
-            (if text (make-property-set 'tempoText text)
-                     (make-property-unset 'tempoText)) 
-            props))
+  (let* ((range-tempo? (pair? tempo))
+        (tempo-count (if range-tempo?
+                         (round (/ (+ (car tempo) (cdr tempo)) 2))
+                         tempo))
+        (props (list
+                (make-property-set 'tempoWholesPerMinute
+                                   (ly:moment-mul (ly:make-moment tempo-count 1)
+                                                  (ly:duration-length duration)))
+                (make-property-set 'tempoUnitDuration duration)
+                (make-property-set 'tempoUnitCount tempo))))
+    (set! props (cons
+                (if text (make-property-set 'tempoText text)
+                     (make-property-unset 'tempoText))
+                props))
     (context-spec-music
-      (make-sequential-music props)
-      'Score)))
+     (make-sequential-music props)
+     'Score)))
 
 (define-ly-syntax-simple (tempoText text)
   (context-spec-music
@@ -247,3 +251,15 @@ into a @code{MultiMeasureTextEvent}."
        (begin
          (set! (ly:music-property ev 'label) label)
          ch))))
+
+(define-ly-syntax (partial parser location dur)
+  "Make a partial measure."
+
+  ;; We use `descend-to-context' here instead of `context-spec-music' to
+  ;; ensure \partial still works if the Timing_translator is moved
+    (descend-to-context
+     (context-spec-music (make-music 'PartialSet
+                                    'origin location
+                                    'partial-duration dur)
+                        'Timing)
+     'Score))