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Io-like Objects
3 points by rincewind 5952 days ago | 1 comment
Differences to Io:

- explicit self paramter for methods to avoid setSlot/updateSlot confusion

- not everything is an object

  (let (set-prototype make-prototype) nil
   (w/uniq bound-meth
  
    (def make-prototype ((o prototype nil))
      (annotate 'prototype (list (table) prototype)))

    (defcall prototype ((table prototype) slot)
      (aif table.slot it
           prototype it.slot))

    (def set-prototype (table slot value)
        (let (table proto) rep.table
             (= table.slot value)))

    (def method (fun)
      (annotate bound-meth fun))

    (defcall proto-object (self message . args)
       (let selfobj (annotate 'proto-object self)
          (aif self.message
             (if (isa it bound-meth) (apply rep.it selfobj args)
                                      it)
             (apply selfobj 'forward message args))))

    (= root-object
         (annotate 'proto-object 
	     (make-prototype:obj forward
                 (method:fn (self message . args)
                           (prn self!name " cannot handle " message))
                  clone
                 (method:fn (self)
                           (annotate 'proto-object (make-prototype rep.self)))
                  set
                 (method:fn (self slot val)
                           (set-prototype rep.self slot val))
                  get
                 (method:fn (self slot) (rep.self slot))
                  print
                 (method:fn (self) (let (tab proto) (rep:rep self) prn.tab))
                  name
                  'proto-object)))))

  (root-object 'set 'with 
     (method:fn (self . args) 
	      (let new self!clone 
		    (map (fn ((k v)) (new 'set k v)) pair.args) 
			 new)))
;try it

  ((= shouter (root-object 'clone)) 'set 'print
    (method:fn (self) (prn:upcase (self 'message))))
  ((shouter 'with 'message "hello world") 'print)


2 points by rincewind 5952 days ago | link

see also:

http://arclanguage.org/item?id=7462

http://arclanguage.org/item?id=7365

http://arclanguage.org/item?id=7530

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