1 ;;; display-lily.scm -- Display music expressions using LilyPond notation
5 ;;; Copyright (C) 2005--2011 Nicolas Sceaux <nicolas.sceaux@free.fr>
8 ;;; - This file defines the procedures used to define display methods for each
9 ;;; music type: define-display-method and define-extra-display-method.
10 ;;; See scm/define-music-display-methods.scm
11 ;;; Display methods are stored in the `display-methods' property of each music
14 ;;; - `music->lily-string' return a string describing a music expression using
15 ;;; LilyPond notation. The special variables *indent*, *previous-duration*,
16 ;;; and *force-duration* influence the indentation level and the display of
19 ;;; - `with-music-match' can be used to destructure a music expression, extracting
20 ;;; some interesting music properties.
23 (define-module (scm display-lily)
24 #:use-module (ice-9 optargs)
25 #:use-module (ice-9 format)
26 #:use-module (ice-9 regex)
27 #:use-module (ice-9 pretty-print)
28 #:use-module (srfi srfi-1)
29 #:use-module (srfi srfi-13)
30 #:use-module (srfi srfi-39)
33 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
35 ;;; Display method definition and call
39 (define-macro (define-display-method music-type vars . body)
40 "Define a display method for a music type and store it in the
41 `display-methods' property of the music type entry found in the
42 `music-name-to-property-table' hash table. Print methods previously
43 defined for that music type are lost.
44 Syntax: (define-display-method MusicType (expression parser)
46 `(let ((type-props (hashq-ref music-name-to-property-table
51 (assoc-set! type-props 'display-methods (list method)))
52 (hashq-set! music-name-to-property-table
57 (define-macro (define-extra-display-method music-type vars . body)
58 "Add a display method for a music type. A primary display method
59 is supposed to have been previously defined with `define-display-method'.
60 This new method should return a string or #f. If #f is returned, the next
61 display method will be called."
62 `(let* ((type-props (hashq-ref music-name-to-property-table
64 (methods (assoc-ref type-props 'display-methods))
65 (new-method (lambda ,vars
68 (assoc-set! type-props
70 (cons new-method methods)))
71 (hashq-set! music-name-to-property-table
76 (define* (tag->lily-string expr #:optional (post-event? #f))
79 (format #f "~a\\tag #'~a" (if post-event? "-" "") tag))
80 (ly:music-property expr 'tags))))
82 (define-public (music->lily-string expr parser)
83 "Print @var{expr}, a music expression, in LilyPond syntax."
85 (let* ((music-type (ly:music-property expr 'name))
86 (procs (assoc-ref (hashq-ref music-name-to-property-table
89 (result-string (and procs (any (lambda (proc)
94 (tag->lily-string expr (post-event? expr))
96 (format #f "%{ Print method not implemented for music type ~a %}"
98 (format #f "%{ expecting a music expression: ~a %}" expr)))
100 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
102 ;;; Music pattern matching
106 (and (symbol? x) (char=? #\? (string-ref (symbol->string x) 0))))
109 (and (pair? x) (eqv? (car x) 'music)))
111 (define (music-list? x)
115 (define (music-or-var-list? x)
118 (or (music? e) (var? e)))
121 (define (key-val-list->alist lst)
122 (define (key-val-list->alist-aux lst prev-result)
125 (key-val-list->alist-aux (cddr lst)
126 (cons (cons (first lst) (second lst))
128 (reverse! (key-val-list->alist-aux lst (list))))
130 (define (gen-condition expr pattern)
131 "Helper function for `with-music-match'.
132 Generate an form that checks if the properties of `expr'
133 match thoses described in `pattern'."
134 (let* (;; all (property . value) found at the first depth in pattern,
135 ;; including a (name . <Musictype>) pair.
136 (pat-all-props (cons (cons 'name (second pattern))
137 (key-val-list->alist (cddr pattern))))
138 ;; all (property . value) pairs found in pattern, where value is not
139 ;; a ?var, a music expression or a music list.
140 (prop-vals (remove (lambda (kons)
141 (or (var? (cdr kons))
143 (music-or-var-list? (cdr kons))))
145 ;; list of (property . element) pairs, where element is a music expression
146 (element-list (filter (lambda (kons) (music? (cdr kons)))
148 ;; list of (property . (e1 e2 ..)) pairs, where (e1 e2 ...) is a
149 ;; list a music expressions
150 (elements-list (filter (lambda (kons) (music-or-var-list? (cdr kons)))
153 ;; a form that checks that `expr' is a music expression
154 ;; before actually accessing its properties...
156 ;; a form that checks that `expr' properties have the same
157 ;; values as those given in `pattern'
158 ,@(map (lambda (prop-val)
159 (let ((prop (car prop-val))
160 (val (cdr prop-val)))
161 `(and (not (null? (ly:music-property ,expr ',prop)))
162 (equal? (ly:music-property ,expr ',prop) ,val))))
164 ;; build the test condition for each element found in a (property . element) pair.
165 ;; (typically, property will be 'element)
166 ,@(map (lambda (prop-element)
167 (gen-condition `(ly:music-property ,expr ',(car prop-element)) (cdr prop-element)))
169 ;; build the test conditions for each element found in a (property . (e1 e2 ...)) pair.
170 ;; this requires accessing to an element of a list, hence the index.
171 ;; (typically, property will be 'elements)
172 ,@(map (lambda (prop-elements)
175 `(and ,@(map (lambda (e)
176 (set! index (1+ index))
178 (gen-condition `(and (> (length (ly:music-property ,expr ',(car prop-elements)))
180 (list-ref (ly:music-property ,expr ',(car prop-elements))
184 (cdr prop-elements)))))
187 (define (gen-bindings expr pattern)
188 "Helper function for `with-music-match'.
189 Generate binding forms by looking for ?var symbol in pattern."
190 (let* (;; all (property . value) found at the first depth of pattern,
191 ;; including a (name . <Musictype>) pair.
192 (pat-all-props (cons (cons 'name (second pattern))
193 (key-val-list->alist (cddr pattern))))
194 ;; all (property . ?var) pairs
195 (prop-vars (filter (lambda (kons) (var? (cdr kons)))
197 ;; list of (property . element) pairs, where element is a music expression
198 (element-list (filter (lambda (kons) (music? (cdr kons)))
200 ;; list of (property . (e1 e2 ..)) pairs, where (e1 e2 ...) is a
201 ;; list a music expressions
202 (elements-list (filter (lambda (kons) (music-or-var-list? (cdr kons)))
205 ;; the binding form for the ?var variable found in pattern (first depth).
206 ;; ?var is bound to the value of `expr' property
207 (map (lambda (prop-var)
208 `(,(cdr prop-var) (ly:music-property ,expr ',(car prop-var))))
210 ;; generate bindings for each element found in a (property . element) pair.
211 ;; (typically, property will be 'element)
212 (append-map (lambda (prop-element)
213 (gen-bindings `(ly:music-property ,expr ',(car prop-element))
216 ;; generate bindings for each element found in a (property . (e1 e2 ...)) pair
217 ;; (typically, property will be 'elements)
218 (append-map (lambda (prop-elements)
220 (append-map (lambda (e)
221 (set! index (1+ index))
223 `((,e (list-ref (ly:music-property ,expr ',(car prop-elements)) ,index)))
224 (gen-bindings `(list-ref (ly:music-property ,expr ',(car prop-elements))
227 (cdr prop-elements))))
230 (define-macro (with-music-match music-expr+pattern . body)
231 "If `music-expr' matches `pattern', call `body'. `pattern' should look like:
235 element (music <MusicType> ...)
236 elements ((music <MusicType> ...)
238 (music <MusicType> ...)))
239 The properties of `music-expr' are checked against the values given in the
240 pattern (the name property being the <MusicType> symbol after the `music'
241 keyword), then all music expression found in its properties (such as 'element
243 When ?var is found instead of a property value, ?var is bound that property value,
244 as read inside `music-expr'. ?var may also be used to refere to a whole music
245 expression inside an elements list for instance. These bindings are accessible
247 (let ((music-expr (first music-expr+pattern))
248 (pattern (second music-expr+pattern))
250 `(let ((,expr-sym ,music-expr))
251 (if ,(gen-condition expr-sym pattern)
252 (let ,(gen-bindings expr-sym pattern)
256 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
258 ;;; Special parameters
262 (define-public *indent* (make-parameter 0))
264 ;;; set to #t to force duration printing
265 (define-public *force-duration* (make-parameter #f))
267 ;;; last duration found
268 (define-public *previous-duration* (make-parameter (ly:make-duration 2)))
270 ;;; Set to #t to force a line break with some kinds of expressions (eg sequential music)
271 (define *force-line-break* (make-parameter #t))
272 (define *max-element-number-before-break* (make-parameter 6))
274 ;; \times factor (used in durations)
275 (define *time-factor-denominator* (make-parameter #f))
276 (define *time-factor-numerator* (make-parameter #f))
278 (define *current-context* (make-parameter 'Bottom))
280 (define *explicit-mode* (make-parameter #t))
282 (define (new-line->lily-string)
283 (format #f "~%~v_" (max 0 (1- (*indent*)))))
286 ;;; music type predicate maker
289 (define (make-music-type-predicate . music-types)
290 (define make-music-type-predicate-aux
295 (or (eqv? (car mtypes) (ly:music-property expr 'name))
296 ((make-music-type-predicate-aux (cdr mtypes)) expr))))))
297 (make-music-type-predicate-aux music-types))
299 (ly:load "define-music-display-methods.scm")