"Define a display method for a music type and store it in the
`display-methods' property of the music type entry found in the
`music-name-to-property-table' hash table. Print methods previously
-defined for that music type are lost.
+defined for that music type are lost.
Syntax: (define-display-method MusicType (expression parser)
- ...body...))"
+ ...body...))"
`(let ((type-props (hashq-ref music-name-to-property-table
- ',music-type '()))
- (method (lambda ,vars
- ,@body)))
+ ',music-type '()))
+ (method (lambda ,vars
+ ,@body)))
(set! type-props
- (assoc-set! type-props 'display-methods (list method)))
+ (assoc-set! type-props 'display-methods (list method)))
(hashq-set! music-name-to-property-table
- ',music-type
- type-props)
+ ',music-type
+ type-props)
method))
(define-macro (define-extra-display-method music-type vars . body)
This new method should return a string or #f. If #f is returned, the next
display method will be called."
`(let* ((type-props (hashq-ref music-name-to-property-table
- ',music-type '()))
- (methods (assoc-ref type-props 'display-methods))
- (new-method (lambda ,vars
- ,@body)))
+ ',music-type '()))
+ (methods (assoc-ref type-props 'display-methods))
+ (new-method (lambda ,vars
+ ,@body)))
(set! type-props
- (assoc-set! type-props
- 'display-methods
- (cons new-method methods)))
+ (assoc-set! type-props
+ 'display-methods
+ (cons new-method methods)))
(hashq-set! music-name-to-property-table
- ',music-type
- type-props)
+ ',music-type
+ type-props)
new-method))
(define* (tag->lily-string expr #:optional (post-event? #f))
(format #f "~{~a ~}"
- (map (lambda (tag)
- (format #f "~a\\tag #'~a" (if post-event? "-" "") tag))
- (ly:music-property expr 'tags))))
+ (map (lambda (tag)
+ (format #f "~a\\tag #'~a" (if post-event? "-" "") tag))
+ (ly:music-property expr 'tags))))
(define* (tweaks->lily-string expr #:optional (post-event? #f))
(format #f "~{~a ~}"
"Print @var{expr}, a music expression, in LilyPond syntax."
(if (ly:music? expr)
(let* ((music-type (ly:music-property expr 'name))
- (procs (assoc-ref (hashq-ref music-name-to-property-table
- music-type '())
- 'display-methods))
- (result-string (and procs (any (lambda (proc)
- (proc expr parser))
- procs))))
- (if result-string
- (format #f "~a~a~a"
+ (procs (assoc-ref (hashq-ref music-name-to-property-table
+ music-type '())
+ 'display-methods))
+ (result-string (and procs (any (lambda (proc)
+ (proc expr parser))
+ procs))))
+ (if result-string
+ (format #f "~a~a~a"
(tag->lily-string expr (post-event? expr))
(tweaks->lily-string expr (post-event? expr))
- result-string)
- (format #f "%{ Print method not implemented for music type ~a %}"
- music-type)))
+ result-string)
+ (format #f "%{ Print method not implemented for music type ~a %}"
+ music-type)))
(format #f "%{ expecting a music expression: ~a %}" expr)))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;
;;; Music pattern matching
-;;;
+;;;
(define (var? x)
(and (symbol? x) (char=? #\? (string-ref (symbol->string x) 0))))
(define (music-or-var-list? x)
(and (pair? x)
(every (lambda (e)
- (or (music? e) (var? e)))
- x)))
+ (or (music? e) (var? e)))
+ x)))
(define (key-val-list->alist lst)
(define (key-val-list->alist-aux lst prev-result)
(if (null? lst)
- prev-result
- (key-val-list->alist-aux (cddr lst)
- (cons (cons (first lst) (second lst))
- prev-result))))
+ prev-result
+ (key-val-list->alist-aux (cddr lst)
+ (cons (cons (first lst) (second lst))
+ prev-result))))
(reverse! (key-val-list->alist-aux lst (list))))
(define (gen-condition expr pattern)
Generate an form that checks if the properties of `expr'
match thoses described in `pattern'."
(let* (;; all (property . value) found at the first depth in pattern,
- ;; including a (name . <Musictype>) pair.
- (pat-all-props (cons (cons 'name (second pattern))
- (key-val-list->alist (cddr pattern))))
- ;; all (property . value) pairs found in pattern, where value is not
- ;; a ?var, a music expression or a music list.
- (prop-vals (remove (lambda (kons)
- (or (var? (cdr kons))
- (music? (cdr kons))
- (music-or-var-list? (cdr kons))))
- pat-all-props))
- ;; list of (property . element) pairs, where element is a music expression
- (element-list (filter (lambda (kons) (music? (cdr kons)))
- pat-all-props))
- ;; list of (property . (e1 e2 ..)) pairs, where (e1 e2 ...) is a
- ;; list a music expressions
- (elements-list (filter (lambda (kons) (music-or-var-list? (cdr kons)))
- pat-all-props)))
- `(and
+ ;; including a (name . <Musictype>) pair.
+ (pat-all-props (cons (cons 'name (second pattern))
+ (key-val-list->alist (cddr pattern))))
+ ;; all (property . value) pairs found in pattern, where value is not
+ ;; a ?var, a music expression or a music list.
+ (prop-vals (remove (lambda (kons)
+ (or (var? (cdr kons))
+ (music? (cdr kons))
+ (music-or-var-list? (cdr kons))))
+ pat-all-props))
+ ;; list of (property . element) pairs, where element is a music expression
+ (element-list (filter (lambda (kons) (music? (cdr kons)))
+ pat-all-props))
+ ;; list of (property . (e1 e2 ..)) pairs, where (e1 e2 ...) is a
+ ;; list a music expressions
+ (elements-list (filter (lambda (kons) (music-or-var-list? (cdr kons)))
+ pat-all-props)))
+ `(and
;; a form that checks that `expr' is a music expression
;; before actually accessing its properties...
(ly:music? ,expr)
;; a form that checks that `expr' properties have the same
;; values as those given in `pattern'
,@(map (lambda (prop-val)
- (let ((prop (car prop-val))
- (val (cdr prop-val)))
- `(and (not (null? (ly:music-property ,expr ',prop)))
- (equal? (ly:music-property ,expr ',prop) ,val))))
- prop-vals)
+ (let ((prop (car prop-val))
+ (val (cdr prop-val)))
+ `(and (not (null? (ly:music-property ,expr ',prop)))
+ (equal? (ly:music-property ,expr ',prop) ,val))))
+ prop-vals)
;; build the test condition for each element found in a (property . element) pair.
;; (typically, property will be 'element)
,@(map (lambda (prop-element)
- (gen-condition `(ly:music-property ,expr ',(car prop-element)) (cdr prop-element)))
- element-list)
+ (gen-condition `(ly:music-property ,expr ',(car prop-element)) (cdr prop-element)))
+ element-list)
;; build the test conditions for each element found in a (property . (e1 e2 ...)) pair.
;; this requires accessing to an element of a list, hence the index.
;; (typically, property will be 'elements)
,@(map (lambda (prop-elements)
- (let ((ges (gensym))
- (index -1))
- `(and ,@(map (lambda (e)
- (set! index (1+ index))
- (if (music? e)
- (gen-condition `(and (> (length (ly:music-property ,expr ',(car prop-elements)))
- ,index)
- (list-ref (ly:music-property ,expr ',(car prop-elements))
- ,index))
- e)
- #t))
- (cdr prop-elements)))))
- elements-list))))
+ (let ((ges (gensym))
+ (index -1))
+ `(and ,@(map (lambda (e)
+ (set! index (1+ index))
+ (if (music? e)
+ (gen-condition `(and (> (length (ly:music-property ,expr ',(car prop-elements)))
+ ,index)
+ (list-ref (ly:music-property ,expr ',(car prop-elements))
+ ,index))
+ e)
+ #t))
+ (cdr prop-elements)))))
+ elements-list))))
(define (gen-bindings expr pattern)
"Helper function for `with-music-match'.
Generate binding forms by looking for ?var symbol in pattern."
(let* (;; all (property . value) found at the first depth of pattern,
- ;; including a (name . <Musictype>) pair.
- (pat-all-props (cons (cons 'name (second pattern))
- (key-val-list->alist (cddr pattern))))
- ;; all (property . ?var) pairs
- (prop-vars (filter (lambda (kons) (var? (cdr kons)))
- pat-all-props))
- ;; list of (property . element) pairs, where element is a music expression
- (element-list (filter (lambda (kons) (music? (cdr kons)))
- pat-all-props))
- ;; list of (property . (e1 e2 ..)) pairs, where (e1 e2 ...) is a
- ;; list a music expressions
- (elements-list (filter (lambda (kons) (music-or-var-list? (cdr kons)))
- pat-all-props)))
- (append
+ ;; including a (name . <Musictype>) pair.
+ (pat-all-props (cons (cons 'name (second pattern))
+ (key-val-list->alist (cddr pattern))))
+ ;; all (property . ?var) pairs
+ (prop-vars (filter (lambda (kons) (var? (cdr kons)))
+ pat-all-props))
+ ;; list of (property . element) pairs, where element is a music expression
+ (element-list (filter (lambda (kons) (music? (cdr kons)))
+ pat-all-props))
+ ;; list of (property . (e1 e2 ..)) pairs, where (e1 e2 ...) is a
+ ;; list a music expressions
+ (elements-list (filter (lambda (kons) (music-or-var-list? (cdr kons)))
+ pat-all-props)))
+ (append
;; the binding form for the ?var variable found in pattern (first depth).
;; ?var is bound to the value of `expr' property
(map (lambda (prop-var)
- `(,(cdr prop-var) (ly:music-property ,expr ',(car prop-var))))
- prop-vars)
+ `(,(cdr prop-var) (ly:music-property ,expr ',(car prop-var))))
+ prop-vars)
;; generate bindings for each element found in a (property . element) pair.
;; (typically, property will be 'element)
(append-map (lambda (prop-element)
- (gen-bindings `(ly:music-property ,expr ',(car prop-element))
- (cdr prop-element)))
- element-list)
+ (gen-bindings `(ly:music-property ,expr ',(car prop-element))
+ (cdr prop-element)))
+ element-list)
;; generate bindings for each element found in a (property . (e1 e2 ...)) pair
;; (typically, property will be 'elements)
- (append-map (lambda (prop-elements)
- (let ((index -1))
- (append-map (lambda (e)
- (set! index (1+ index))
- (if (var? e)
- `((,e (list-ref (ly:music-property ,expr ',(car prop-elements)) ,index)))
- (gen-bindings `(list-ref (ly:music-property ,expr ',(car prop-elements))
- ,index)
- e)))
- (cdr prop-elements))))
- elements-list))))
+ (append-map (lambda (prop-elements)
+ (let ((index -1))
+ (append-map (lambda (e)
+ (set! index (1+ index))
+ (if (var? e)
+ `((,e (list-ref (ly:music-property ,expr ',(car prop-elements)) ,index)))
+ (gen-bindings `(list-ref (ly:music-property ,expr ',(car prop-elements))
+ ,index)
+ e)))
+ (cdr prop-elements))))
+ elements-list))))
(define-macro (with-music-match music-expr+pattern . body)
"If `music-expr' matches `pattern', call `body'. `pattern' should look like:
property ?var1
element (music <MusicType> ...)
elements ((music <MusicType> ...)
- ?var2
- (music <MusicType> ...)))
+ ?var2
+ (music <MusicType> ...)))
The properties of `music-expr' are checked against the values given in the
pattern (the name property being the <MusicType> symbol after the `music'
keyword), then all music expression found in its properties (such as 'element
or 'elements).
When ?var is found instead of a property value, ?var is bound that property value,
-as read inside `music-expr'. ?var may also be used to refere to a whole music
-expression inside an elements list for instance. These bindings are accessible
+as read inside `music-expr'. ?var may also be used to refere to a whole music
+expression inside an elements list for instance. These bindings are accessible
inside body."
(let ((music-expr (first music-expr+pattern))
- (pattern (second music-expr+pattern))
- (expr-sym (gensym)))
+ (pattern (second music-expr+pattern))
+ (expr-sym (gensym)))
`(let ((,expr-sym ,music-expr))
(if ,(gen-condition expr-sym pattern)
- (let ,(gen-bindings expr-sym pattern)
- ,@body)
- #f))))
+ (let ,(gen-bindings expr-sym pattern)
+ ,@body)
+ #f))))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;
(define make-music-type-predicate-aux
(lambda (mtypes)
(lambda (expr)
- (if (null? mtypes)
- #f
- (or (eqv? (car mtypes) (ly:music-property expr 'name))
- ((make-music-type-predicate-aux (cdr mtypes)) expr))))))
- (make-music-type-predicate-aux music-types))
+ (if (null? mtypes)
+ #f
+ (or (eqv? (car mtypes) (ly:music-property expr 'name))
+ ((make-music-type-predicate-aux (cdr mtypes)) expr))))))
+ (make-music-type-predicate-aux music-types))
(ly:load "define-music-display-methods.scm")
projects / lilypond.git / blobdiff