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;; ============================================================
;; define defstruct macro
(define-macro (defstruct struct-name . fields)
(let* ((name (if (list? struct-name) (car struct-name) struct-name))
(sname (if (string? name) name (symbol->string name)))
(fsname (if (list? struct-name)
(let ((cname (assoc :conc-name (cdr struct-name))))
(if cname
(symbol->string (cadr cname))
sname))
sname))
(make-name (if (list? struct-name)
(let ((cname (assoc :constructor (cdr struct-name))))
(if cname
(cadr cname)
(symbol "make-" sname)))
(symbol "make-" sname)))
(copy-name (if (list? struct-name)
(let ((cname (assoc :copier (cdr struct-name))))
(if cname
(cadr cname)
(symbol "copy-" sname)))
(symbol "copy-" sname)))
(field-names (map (lambda (n)
(symbol->string (if (list? n) (car n) n)))
fields))
(field-types (map (lambda (field)
(if (list? field)
(apply (lambda* (val type read-only) type) (cdr field))
#f))
fields))
(field-read-onlys (map (lambda (field)
(if (list? field)
(apply (lambda* (val type read-only) read-only) (cdr field))
#f))
fields)))
`(begin
(define ,(symbol sname "?")
(lambda (obj)
(and (vector? obj)
(eq? (obj 0) ',(string->symbol sname)))))
(define* (,make-name
,@(map (lambda (n)
(if (and (list? n)
(>= (length n) 2))
(list (car n) (cadr n))
(list n #f)))
fields))
(vector ',(string->symbol sname) ,@(map string->symbol field-names)))
(define ,copy-name copy)
,@(map (let ((ctr 1))
(lambda (n type read-only)
(let ((val (if read-only
`(define ,(symbol fsname "-" n)
(lambda (arg) (arg ,ctr)))
`(define ,(symbol fsname "-" n)
(dilambda
(lambda (arg) (arg ,ctr))
(lambda (arg val) (set! (arg ,ctr) val)))))))
(set! ctr (+ 1 ctr))
val)))
field-names field-types field-read-onlys))))
;; ============================================================
;; Structures
(defstruct rect (x 0.0) (y 0.0) (width 0.0) (height 0.0))
(defstruct point (x 0.0) (y 0.0))
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