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Diffstat (limited to 'yasyn.scm')
| -rw-r--r-- | yasyn.scm | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/yasyn.scm b/yasyn.scm new file mode 100644 index 0000000..2b3cec0 --- /dev/null +++ b/yasyn.scm @@ -0,0 +1,201 @@ +;;"yasyn.scm" YASOS in terms of "object.scm" +;;;From: whumeniu@datap.ca (Wade Humeniuk) + +(require 'object) + +(define yasos:instance? object?) +;; Removed (define yasos:make-instance 'bogus) ;; +;; Removed (define-syntax YASOS:INSTANCE-DISPATCHER ;; alias so compiler can inline for speed +;; (syntax-rules () ((yasos:instance-dispatcher inst) (cdr inst)))) +;; DEFINE-OPERATION + +(define-syntax define-operation + (syntax-rules () + ((define-operation (<name> <inst> <arg> ...) <exp1> <exp2> ...) + ;;=> + (define <name> (make-generic-method + (lambda (<inst> <arg> ...) <exp1> <exp2> ...)))) + + ((define-operation (<name> <inst> <arg> ...) ) ;; no body + ;;=> + (define-operation (<name> <inst> <arg> ...) + (slib:error "Operation not handled" + '<name> + (format #f (if (yasos:instance? <inst>) "#<INSTANCE>" "~s") + <inst>)))))) + +;; DEFINE-PREDICATE + +(define-syntax define-predicate + (syntax-rules () + ((define-predicate <name>) + ;;=> + (define <name> (make-generic-predicate))))) + +;; OBJECT + +(define-syntax object + (syntax-rules () + ((object ((<name> <self> <arg> ...) <exp1> <exp2> ...) ...) + ;;=> + (let ((self (make-object))) + (make-method! self <name> (lambda (<self> <arg> ...) <exp1> <exp2> ...)) + ... + self)))) + +;; OBJECT with MULTIPLE INHERITANCE {First Found Rule} + +(define-syntax object-with-ancestors + (syntax-rules () + ((object-with-ancestors ( (<ancestor1> <init1>) ... ) + ((<name> <self> <arg> ...) <exp1> <exp2> ...) ...) + ;;=> + (let* ((<ancestor1> <init1>) + ... + (self (make-object <ancestor1> ...))) + (make-method! self <name> (lambda (<self> <arg> ...) <exp1> <exp2> ...)) + ... + self)))) + +;; OPERATE-AS {a.k.a. send-to-super} + +; used in operations/methods + +(define-syntax operate-as + (syntax-rules () + ((operate-as <component> <op> <composit> <arg> ...) ;; What is <composit> ??? + ;;=> + ((get-method <component> <op>) <composit> <arg> ...)))) + + + +;; SET & SETTER + + +(define-syntax set + (syntax-rules () + ((set (<access> <index> ...) <newval>) + ((yasos:setter <access>) <index> ... <newval>) + ) + ((set <var> <newval>) + (set! <var> <newval>) + ) +) ) + + +(define yasos:add-setter 'bogus) +(define yasos:remove-setter-for 'bogus) + +(define yasos:setter + (let ( (known-setters (list (cons car set-car!) + (cons cdr set-cdr!) + (cons vector-ref vector-set!) + (cons string-ref string-set!)) + ) + (added-setters '()) + ) + + (set! yasos:add-setter + (lambda (getter setter) + (set! added-setters (cons (cons getter setter) added-setters))) + ) + (set! yasos:remove-setter-for + (lambda (getter) + (cond + ((null? added-setters) + (slib:error "REMOVE-SETTER-FOR: Unknown getter" getter) + ) + ((eq? getter (caar added-setters)) + (set! added-setters (cdr added-setters)) + ) + (else + (let loop ((x added-setters) (y (cdr added-setters))) + (cond + ((null? y) (slib:error "REMOVE-SETTER-FOR: Unknown getter" + getter)) + ((eq? getter (caar y)) (set-cdr! x (cdr y))) + (else (loop (cdr x) (cdr y))) + ) ) ) + ) ) ) + + (letrec ( (self + (lambda (proc-or-operation) + (cond ((assq proc-or-operation known-setters) => cdr) + ((assq proc-or-operation added-setters) => cdr) + (else (proc-or-operation self))) ) + ) ) + self) +) ) + + + +(define (yasos:make-access-operation <name>) + (letrec ( (setter-dispatch + (lambda (inst . args) + (cond + ((and (yasos:instance? inst) + (get-method inst setter-dispatch)) + => (lambda (method) (apply method (cons inst args))) + ) + (else #f))) + ) + (self + (lambda (inst . args) + (cond + ((eq? inst yasos:setter) setter-dispatch) ; for (setter self) + ((and (yasos:instance? inst) + (get-method inst self)) + => (lambda (method) (apply method (cons inst args))) + ) + (else (slib:error "Operation not handled" <name> inst)) + ) ) + ) + ) + + self +) ) + +(define-syntax define-access-operation + (syntax-rules () + ((define-access-operation <name>) + ;=> + (define <name> (yasos:make-access-operation '<name>)) +) ) ) + + + +;;--------------------- +;; general operations +;;--------------------- + +(define-operation (yasos:print obj port) + (format port + ;; if an instance does not have a PRINT operation.. + (if (yasos:instance? obj) "#<INSTANCE>" "~s") + obj +) ) + +(define-operation (yasos:size obj) + ;; default behavior + (cond + ((vector? obj) (vector-length obj)) + ((list? obj) (length obj)) + ((pair? obj) 2) + ((string? obj) (string-length obj)) + ((char? obj) 1) + (else + (slib:error "Operation not supported: size" obj)) +) ) + +(require 'format) + +;;; exports: + +(define print yasos:print) ; print also in debug.scm +(define size yasos:size) +(define add-setter yasos:add-setter) +(define remove-setter-for yasos:remove-setter-for) +(define setter yasos:setter) + +(provide 'oop) ;in case we were loaded this way. +(provide 'yasos) |