Import Upstream version 2a6upstream/2a6

1 files changed, 201 insertions, 0 deletions

diff --git a/yasyn.scm b/yasyn.scm
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+;;"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)