(provide 'mockery.scm)

(define (outlet-member obj e)
  (or (eq? obj e)
      (and (not (eq? obj (rootlet)))
	   (outlet-member (outlet obj) e))))

(define (make-method f accessor)
  (lambda args
    (if (let? (car args)) 
	(apply f (accessor (car args)) (cdr args))
	(apply f (car args) (accessor (cadr args)) (cddr args)))))

(define (make-object . args)
  (openlet
   (apply inlet args)))


(define (mock->string obj . args)
  (dynamic-wind
      (lambda () (coverlet obj))
      (lambda () (apply #_object->string (obj 'value) args))
      (lambda () (openlet obj))))



;;; --------------------------------------------------------------------------------

(define *mock-vector*
  (let ((mock-vector? #f))
    (let ((mock-vector-class
	   (openlet  
	    (inlet 'morally-equal?     (make-method #_morally-equal? (lambda (obj) (obj 'value))) ; see comment below

		   'local-set!         (lambda (obj i val)          ; reactive-vector uses this as a hook into vector-set!
					 (if (vector? (obj 'value))
					     (#_vector-set! (obj 'value) i val)
					     (error 'wrong-type-arg "vector-set! ~S ~S ~S" obj i val))) ; the wrong arg here is 'i
		   'vector-set!        (lambda (obj i val) ((obj 'local-set!) obj i val) val)
		   'let-set!           (lambda (obj i val) ((obj 'local-set!) obj i val) val)

		   'vector-ref         (lambda (obj i) 
					 (if (mock-vector? obj)
					     (#_vector-ref (obj 'value) i)
					     (error 'wrong-type-arg "vector-ref ~S ~S" obj i)))

		   'let-ref            (lambda (obj i) (#_vector-ref (obj 'value) i))   ; the implicit case, so 'i can't be the culprit
		   'vector-length      (lambda (obj) (#_vector-length (obj 'value)))
		   'map                (lambda (f obj) (map f (obj 'value)))
		   'for-each           (lambda (f obj) (for-each f (obj 'value)))
		   'vector-append      (make-method #_vector-append (lambda (obj) (obj 'value)))
		   'reverse            (lambda (obj) (#_reverse (obj 'value)))
		   'sort!              (lambda (obj f) (#_sort! (obj 'value) f))
		   'arity              (lambda (obj) (#_arity (obj 'value)))
		   'object->string     (lambda* (obj (w #t)) "#<mock-vector-class>")
		   'vector-dimensions  (lambda (obj) (#_vector-dimensions (obj 'value)))
		   'fill!              (lambda (obj val) (#_fill! (obj 'value) val))

		   'vector->list       (lambda (obj . args) 
					 (if (mock-vector? obj)
					     (apply #_vector->list (obj 'value) args)
					     (error 'wrong-type-arg "vector->list ~S ~S" obj args)))

		   'make-shared-vector (lambda* (obj dim (off 0))
					 (if (mock-vector? obj)
					     (#_make-shared-vector (obj 'value) dim off)
					     (error 'wrong-type-arg "make-shared-vector ~S ~S ~S" obj dim off)))

		   'vector-fill!       (lambda* (obj val (start 0) end) 
					 (if (mock-vector? obj)
					     (#_vector-fill! (obj 'value) val start (or end (#_vector-length (obj 'value))))
					     (error 'wrong-type-arg "vector-fill! ~S ~S ~S ~S" obj val start end)))

		   'copy               (lambda* (source dest . args)
					 ;; copy by itself does not make a new vector, but if no dest we
					 ;;   need a copy of source, so use coverlet/openlet to make sure
					 ;;   we aren't caught in an infinite recursion.
					 (if (mock-vector? source)
					     (if (and dest (not (let? dest)))
						 (apply copy (source 'value) dest args)
						 (let ((nobj (or dest 
								 (dynamic-wind
								     (lambda () (coverlet source))
								     (lambda () (openlet (copy source)))
								     (lambda () (openlet source))))))
						   (if dest
						       (apply copy (source 'value) (nobj 'value) args)
						       (set! (nobj 'value) (copy (source 'value))))
						   nobj))
					     (error 'wrong-type-arg "copy ~S ~S ~S" source dest args)))
		   'vector?            (lambda (obj) #t)
		   'values             (lambda (obj . args) (obj 'value))
		   'length             (lambda (obj) (#_vector-length (obj 'value)))
		   'class-name         'mock-vector))))
      
      (define* (make-mock-vector len (init #<unspecified>))
	(openlet (sublet mock-vector-class 
		   'value (#_make-vector len init)
		   'object->string mock->string)))
      
      (define (mock-vector . args)
	(let ((v (make-mock-vector 0)))
	  (set! (v 'value) (apply #_vector args))
	  v))
      
      (set! mock-vector? (lambda (obj)
			   (and (openlet? obj)
				(outlet-member obj mock-vector-class))))
      
      (curlet))))


#|
;;; the morally-equal? method should track circles (via cyclic-sequences?)
;;;   as it is now, this code cores up indefinitely:
(let ((v1 ((*mock-vector* 'mock-vector) 1 2 3 4))
      (v2 ((*mock-vector* 'mock-vector) 2 3 4))
      (v3 #(1 2 3 4))
      (v4 #(2 3 4)))
  (vector-set! v2 0 v1)
  (vector-set! v1 0 v2)
  (vector-set! v4 0 v3)
  (vector-set! v3 0 v4)
  (morally-equal? v1 v3))
;;; but how to make this cooperate with the built-in method -- we should call cyclic-sequences just once
|#

#|
;; vector that grows to accommodate vector-set!

(define stretchable-vector-class
  (let ((local-ref (lambda (obj index)
		     (if (>= index (length (obj 'value)))
			 (obj 'initial-element)
			 (#_vector-ref (obj 'value) index))))
	(local-set! (lambda (obj index val)
		      (if (>= index (length (obj 'value)))
			  (set! (obj 'value) (copy (obj 'value) (make-vector (+ index 8) (obj 'initial-element)))))
		      (#_vector-set! (obj 'value) index val))))
    (openlet
     (sublet (*mock-vector* 'mock-vector-class)
       'value (vector)
       'object->string mock->string
       'initial-element #f
       'vector-ref local-ref
       'let-ref local-ref
       'vector-set! local-set!
       'let-set! local-set!))))
|#


;;; --------------------------------------------------------------------------------

(define *mock-hash-table*
  (let ((mock-hash-table? #f))
    (let ((mock-hash-table-class
	   (openlet
	    (inlet 'morally-equal?     (lambda (x y)          (#_morally-equal? (x 'mock-hash-table-table) y))
		   'hash-table-ref     (lambda (obj key)      (#_hash-table-ref (obj 'mock-hash-table-table) key))
		   'hash-table-set!    (lambda (obj key val)  (#_hash-table-set! (obj 'mock-hash-table-table) key val))
		   'hash-table-size    (lambda (obj)          (#_hash-table-size (obj 'mock-hash-table-table)))
		   'hash-table-entries (lambda (obj)          (#_hash-table-entries (obj 'mock-hash-table-table)))
		   'make-hash-table-iterator (lambda (obj)    (#_make-hash-table-iterator (obj 'mock-hash-table-table)))
		   'let-ref-fallback   (lambda (obj key)      (#_hash-table-ref (obj 'mock-hash-table-table) key))
		   'let-set!-fallback  (lambda (obj key val)  (#_hash-table-set! (obj 'mock-hash-table-table) key val))
		   
		   ;; the fallbacks are needed because hash-tables and lets use exactly the same syntax in implicit indexing:
		   ;;   (x 'y) but s7 can't tell that in this one case, we actually want the 'y to be a key not a field.
		   ;;   So, to avoid infinite recursion in let-ref (implicit index), if let-ref can't find the let field,
		   ;;   and the let has 'let-ref|set!-fallback, let-ref|set! passes the argument to that function rather than
		   ;;   return #<undefined>.
		   ;;
		   ;; (round (openlet (inlet 'round (lambda (obj) (#_round (obj 'value))) 'let-ref-fallback (lambda args 3)))) -> 3
		   
		   'map                (lambda (f obj)        (map f (obj 'mock-hash-table-table)))
		   'for-each           (lambda (f obj)        (for-each f (obj 'mock-hash-table-table)))
		   'fill!              (lambda (obj val)      (#_fill! (obj 'mock-hash-table-table) val))
		   'reverse            (lambda (obj)          (#_reverse (obj 'mock-hash-table-table)))
		   'object->string     (lambda* (obj (w #t))  "#<mock-hash-table-class>")
		   'arity              (lambda (obj)          (#_arity (obj 'mock-hash-table-table)))
		   'copy               (lambda* (source dest . args)
					 (if (mock-hash-table? source)
					     (if (and dest (not (let? dest)))
						 (apply copy (obj 'mock-hash-table-table) dest args)
						 (let ((nobj (or dest (openlet (copy (coverlet source))))))
						   (openlet source)
						   (set! (nobj 'mock-hash-table-table) (copy (source 'mock-hash-table-table)))
						   nobj))
					     (error 'wrong-type-arg "copy ~S ~S ~S" source dest args)))
		   'hash-table?        (lambda (obj) #t)
		   'values             (lambda (obj . args) (obj 'mock-hash-table-table))
		   'length             (lambda (obj)          (#_hash-table-size (obj 'mock-hash-table-table)))
		   'class-name         'mock-hash-table))))

      (define* (make-mock-hash-table (len 511))
	(openlet 
	 (sublet mock-hash-table-class 
	   'mock-hash-table-table (#_make-hash-table len)
	   'object->string (lambda (obj . args) ; can't use mock->string because the value is not in the 'value field
			     (dynamic-wind
				 (lambda () (coverlet obj))
				 (lambda () (apply #_object->string (obj 'mock-hash-table-table) args))
				 (lambda () (openlet obj)))))))
      
      (define (mock-hash-table . args)
	(let ((v (make-mock-hash-table)))
	  (set! (v 'mock-hash-table-table) (apply #_hash-table args))
	  v))
      
      (define (mock-hash-table* . args)
	(let ((v (make-mock-hash-table)))
	  (set! (v 'mock-hash-table-table) (apply #_hash-table* args))
	  v))
      
      (set! mock-hash-table? (lambda (obj)
			       (and (openlet? obj)
				    (outlet-member obj mock-hash-table-class))))
      
      (curlet))))


#|
;; hash-table that returns a special identifier when key is not in the table

(define gloomy-hash-table
  (openlet
   (sublet (*mock-hash-table* 'mock-hash-table-class) ; ideally this would be a separate (not copied) gloomy-hash-table-class 
     'mock-hash-table-table #f
     'false (gensym)
     'not-a-key #f
     'hash-table-ref (lambda (obj key)
		       (let ((val (#_hash-table-ref (obj 'mock-hash-table-table) key)))
			 (if (eq? val (obj 'false))
			     #f
			     (or val (obj 'not-a-key)))))
     'hash-table-key? (lambda (obj key)
			(#_hash-table-ref (obj 'mock-hash-table-table) key)))))

(define (hash-table-key? obj key) 
  ((obj 'hash-table-key?) obj key))

(define* (make-gloomy-hash-table (len 511) not-a-key)
  (let ((ht (copy gloomy-hash-table)))
    (set! (ht 'mock-hash-table-table) (make-hash-table len))
    (set! (ht 'not-a-key) not-a-key)
    ht))
|#



;;; --------------------------------------------------------------------------------

(define *mock-string*
  (let ((mock-string? #f))
    (let ((mock-string-class
	   (openlet
	    (inlet 'morally-equal?         (lambda (x y) (#_morally-equal? (x 'value) y))
		   'reverse                (lambda (obj) (#_reverse (obj 'value)))
		   'object->string         (lambda* (obj (w #t)) "#<mock-string-class>")
		   'arity                  (lambda (obj) (#_arity (obj 'value)))
		   'let-ref                (lambda (obj i) (#_string-ref (obj 'value) i))           ; these are the implicit cases
		   'let-set!               (lambda (obj i val) (string-set! (obj 'value) i val))
		   'string-length          (lambda (obj) (#_string-length (obj 'value)))
		   'map                    (lambda (f obj) (map f (obj 'value)))
		   'for-each               (lambda (f obj) (for-each f (obj 'value)))
		   'string->list           (make-method #_string->list (lambda (obj) (obj 'value)))
		   'string-append          (make-method #_string-append (lambda (obj) (obj 'value)))
		   'string-copy            (lambda (obj) (#_string-copy (obj 'value)))
		   'string=?               (make-method #_string=? (lambda (obj) (obj 'value)))
		   'string<?               (make-method #_string<? (lambda (obj) (obj 'value)))
		   'string>?               (make-method #_string>? (lambda (obj) (obj 'value)))
		   'string<=?              (make-method #_string<=? (lambda (obj) (obj 'value)))
		   'string>=?              (make-method #_string>=? (lambda (obj) (obj 'value)))
		   'string-ci=?            (make-method #_string-ci=? (lambda (obj) (obj 'value)))
		   'string-ci<?            (make-method #_string-ci<? (lambda (obj) (obj 'value)))
		   'string-ci>?            (make-method #_string-ci>? (lambda (obj) (obj 'value)))
		   'string-ci<=?           (make-method #_string-ci<=? (lambda (obj) (obj 'value)))
		   'string-ci>=?           (make-method #_string-ci>=? (lambda (obj) (obj 'value)))
		   'string-downcase        (lambda (obj) (#_string-downcase (obj 'value)))
		   'string-upcase          (lambda (obj) (#_string-upcase (obj 'value)))
		   'string->symbol         (lambda (obj) (#_string->symbol (obj 'value)))
		   'symbol                 (lambda (obj) (#_symbol (obj 'value)))
		   'gensym                 (lambda (obj) (#_gensym (obj 'value)))
		   'make-keyword           (lambda (obj) (#_make-keyword (obj 'value)))
		   'open-input-string      (lambda (obj) (#_open-input-string (obj 'value)))
		   'call-with-input-string (lambda (obj f) (#_call-with-input-string (obj 'value) f))
		   'with-input-from-string (lambda (obj f) (#_with-input-from-string (obj 'value) f))
		   'directory?             (lambda (obj) (#_directory? (obj 'value)))
		   'file-exists?           (lambda (obj) (#_file-exists? (obj 'value)))
		   'getenv                 (lambda (obj) (#_getenv (obj 'value)))
		   'delete-file            (lambda (obj) (#_delete-file (obj 'value)))
		   'system                 (lambda* (obj cap) (#_system (obj 'value) cap))
		   '->bytevector           (lambda (obj) (#_->bytevector (obj 'value))) ; this is in-place! 
		   'load                   (lambda* (obj (e (curlet))) (#_load (obj 'value) e))
		   'eval-string            (lambda* (obj (e (curlet))) (#_eval-string (obj 'value) e))
		   'char-position          (make-method #_char-position (lambda (obj) (obj 'value)))

		   'format                 (make-method #_format (lambda (obj) (obj 'value)))
		   'string-fill!           (lambda* (obj val (start 0) end) 
					     (if (mock-string? obj)
						 (#_string-fill! (obj 'value) val start (or end (#_string-length (obj 'value))))
						 (error 'wrong-type-arg "string-fill! ~S ~S ~S ~S" obj val start end)))
		   
		   'fill!                  (lambda (obj val) 
					     (if (mock-string? obj)
						 (#_fill! (obj 'value) val)
						 (error 'wrong-type-arg "fill! ~S ~S" obj val)))
		   
		   'copy                   (lambda* (obj . args) 
					     (if (mock-string? obj)
						 (apply #_copy (obj 'value) args)
						 (error 'wrong-type-arg "copy ~S ~S" obj args)))
		   
		   'substring              (lambda (obj . args) 
					     (if (mock-string? obj)
						 (apply #_substring (obj 'value) args)
						 (error 'wrong-type-arg "substring ~S ~S" obj args)))
		   
		   'string->number         (lambda* (obj (r 10))
					     (if (mock-string? obj)
						 (#_string->number (obj 'value) r)
						 (error 'wrong-type-arg "string->number ~S ~S" obj r)))
		   
		   'write-string           (lambda (obj . args) 
					     (if (mock-string? obj)
						 (apply #_write-string (obj 'value) args)
						 (error 'wrong-type-arg "write-string ~S ~S" obj args)))
		   
		   'string-position        (lambda* (s1 s2 (start 0))
					     (if (mock-string? s1)
						 (#_string-position (s1 'value) s2 start)
						 (if (mock-string? s2)
						     (#_string-position s1 (s2 'value) start)
						     (error 'wrong-type-arg "write-string ~S ~S ~S" s1 s2 start))))
		   'string-ref             (lambda (obj i) 
					     (if (mock-string? obj)
						 (#_string-ref (obj 'value) i)
						 (error 'wrong-type-arg "string-ref ~S ~S" obj i)))
		   
		   'string-set!            (lambda (obj i val) 
					     (if (mock-string? obj)
						 (#_string-set! (obj 'value) i val)
						 (error 'wrong-type-arg "string-set! ~S ~S ~S" obj i val)))
		   
		   'string?                (lambda (obj) #t)
		   'values                 (lambda (obj . args) (obj 'value))
		   'length                 (lambda (obj) (#_string-length (obj 'value)))
		   'class-name             'mock-string))))
      
      (define* (make-mock-string len (init #\null))
	(openlet (sublet mock-string-class 
		   'value (#_make-string len init)
		   'object->string (lambda* (obj (w #t)) (#_object->string (obj 'value) w)))))
      
      (define (mock-string . args)
	(let ((v (make-mock-string 0)))
	  (set! (v 'value) 
		(if (string? (car args))
		    (car args)
		    (apply #_string args)))
	  v))
      
      (set! mock-string? (lambda (obj)
			   (and (openlet? obj)
				(outlet-member obj mock-string-class))))
      
      (curlet))))

#|
;; string that is always the current time of day
(require libc.scm)

(define time-string
  (let ((daytime (lambda args
		   (with-let (sublet *libc*)
		     (let ((timestr (make-string 64))) 
		       (let ((len (strftime timestr 64 "%a %d-%b-%Y %H:%M %Z"
					    (localtime 
					     (time.make (time (c-pointer 0)))))))
			 (substring timestr 0 len)))))))
    (openlet
     (sublet (*mock-string* 'mock-string-class)
       'let-ref-fallback daytime
       'object->string daytime))))

;; similarly ("JIT data"):
(define ? (openlet 
	   (inlet 'object->string (lambda (obj . args) 
				    (apply #_object->string (owlet) args)))))

|#


;;; --------------------------------------------------------------------------------

(define *mock-char*
  (let ((mock-char? #f))
    (let ((mock-char-class
	   (openlet
	    (inlet 'morally-equal?     (lambda (x y) (#_morally-equal? (x 'value) y))
		   'char-upcase        (lambda (obj) (#_char-upcase (obj 'value)))
		   'char-downcase      (lambda (obj) (#_char-downcase (obj 'value)))
		   'char->integer      (lambda (obj) (#_char->integer (obj 'value)))
		   'char-upper-case?   (lambda (obj) (#_char-upper-case? (obj 'value)))
		   'char-lower-case?   (lambda (obj) (#_char-lower-case? (obj 'value)))
		   'char-alphabetic?   (lambda (obj) (#_char-alphabetic? (obj 'value)))
		   'char-numeric?      (lambda (obj) (#_char-numeric? (obj 'value)))
		   'char-whitespace?   (lambda (obj) (#_char-whitespace? (obj 'value)))
		   'char=?             (make-method #_char=? (lambda (obj) (obj 'value)))
		   'char<?             (make-method #_char<? (lambda (obj) (obj 'value)))
		   'char>?             (make-method #_char>? (lambda (obj) (obj 'value)))
		   'char<=?            (make-method #_char<=? (lambda (obj) (obj 'value)))
		   'char>=?            (make-method #_char>=? (lambda (obj) (obj 'value)))
		   'char-ci=?          (make-method #_char-ci=? (lambda (obj) (obj 'value)))
		   'char-ci<?          (make-method #_char-ci<? (lambda (obj) (obj 'value)))
		   'char-ci>?          (make-method #_char-ci>? (lambda (obj) (obj 'value)))
		   'char-ci<=?         (make-method #_char-ci<=? (lambda (obj) (obj 'value)))
		   'char-ci>=?         (make-method #_char-ci>=? (lambda (obj) (obj 'value)))
		   'string             (make-method #_string (lambda (obj) (obj 'value)))
		   'object->string     (lambda (obj . args) "#<mock-char-class>")
		   'arity              (lambda (obj) (#_arity (obj 'value)))
		   'format             (make-method #_format (lambda (obj) (obj 'value)))
		   'make-string        (make-method #_make-string (lambda (obj) (obj 'value)))
		   'char-position      (make-method #_char-position (lambda (obj) (obj 'value)))
		   
		   'write-char         (lambda (obj . args) 
					 (if (mock-char? obj)
					     (apply #_write-char (obj 'value) args)
					     (error 'wrong-type-arg "write-char: ~S ~S" obj args)))
		   
		   'string-set!        (lambda (obj ind val)
					 (if (and (string? obj)
						  (integer? ind))
					     (#_string-set! obj ind (val 'value))
					     (error 'wrong-type-arg "string-set! ~S ~S ~S" obj ind val)))
		   
		   'copy               (lambda (obj . args) 
					 (if (mock-char? obj)
					     (obj 'value)
					     (error 'wrong-type-arg "copy: ~S ~S" obj args)))
		   'char?              (lambda (obj) #t)
		   'class-name         'mock-char
		   'values             (lambda (obj . args) (obj 'value))))))
      
      (define (mock-char c) 
	(if (and (char? c)
		 (not (let? c)))
	    (openlet
	     (sublet (*mock-char* 'mock-char-class)
	       'value c
	       'object->string mock->string))
	    (error 'wrong-type-arg "mock-char ~S is not a char" c)))
      
      (set! mock-char? (lambda (obj)
			 (and (openlet? obj)
			      (outlet-member obj mock-char-class))))
      
      (curlet))))

#|
;;; eventually I'll conjure up unichars like (define lambda (bytevector #xce #xbb)) via mock-char,
;;;   then combine those into unistring via mock-string
;;;
;;; (string-length obj)->g_utf8_strlen etc 
;;;   (g_unichar_isalpha (g_utf8_get_char (bytevector #xce #xbb))) -> #t
;;;   (g_utf8_strlen (bytevector #xce #xbb #xce #xba) 10) -> 2
;;;   (g_utf8_normalize (bytevector #xce #xbb #xce #xba) 4 G_NORMALIZE_DEFAULT)
;;;   but the ones that return gunichar (toupper) currently don't return a bytevector or a string
;;;   maybe gunichar->bytevector?
;;;   need glib.scm, or unicode.scm to load the stuff
|#



;;; --------------------------------------------------------------------------------

(define *mock-number*
  (let ((mock-number? #f))

    (define* (range-method-1 func arg start end)
      (if (not end)
	  (func arg (start 'value))
	  (if (not (let? start))
	      (func arg start (end 'value))
	      (apply func arg (start 'value) end ()))))

    (define* (range-method-2 func arg1 arg2 start end)
      (if (not end)
	  (func arg1 arg2 (start 'value))
	  (if (not (let? start))
	      (func arg1 arg2 start (end 'value))
	      (apply func arg1 arg2 (start 'value) end ()))))

    (let ((mock-number-class
	   (openlet
	    (inlet 
		   'morally-equal?   (lambda (x y) (#_morally-equal? (x 'value) y))
		   'object->string   (lambda (obj . args) "#<mock-number-class>")
		   'arity            (lambda (obj) (#_arity (obj 'value)))
		   'real-part        (lambda (obj) (#_real-part (obj 'value)))
		   'imag-part        (lambda (obj) (#_imag-part (obj 'value)))
		   'numerator        (lambda (obj) (#_numerator (obj 'value)))
		   'denominator      (lambda (obj) (#_denominator (obj 'value)))
		   'even?            (lambda (obj) (#_even? (obj 'value)))
		   'odd?             (lambda (obj) (#_odd? (obj 'value)))
		   'zero?            (lambda (obj) (#_zero? (obj 'value)))
		   'positive?        (lambda (obj) (#_positive? (obj 'value)))
		   'negative?        (lambda (obj) (#_negative? (obj 'value)))
		   'infinite?        (lambda (obj) (#_infinite? (obj 'value)))
		   'nan?             (lambda (obj) (#_nan? (obj 'value)))
		   'make-polar       (make-method #_make-polar (lambda (obj) (obj 'value)))
		   'make-rectangular (make-method #_make-rectangular (lambda (obj) (obj 'value)))
		   'make-complex     (make-method #_make-rectangular (lambda (obj) (obj 'value)))
		   'make-random-state (make-method #_make-random-state (lambda (obj) (obj 'value)))
		   'magnitude        (lambda (obj) (#_magnitude (obj 'value)))
		   'angle            (lambda (obj) (#_angle (obj 'value)))
		   'rationalize      (make-method #_rationalize (lambda (obj) (obj 'value)))
		   'abs              (lambda (obj) (#_abs (obj 'value)))
		   'exp              (lambda (obj) (#_exp (obj 'value)))
		   'log              (make-method #_log (lambda (obj) (obj 'value)))
		   'sin              (lambda (obj) (#_sin (obj 'value)))
		   'cos              (lambda (obj) (#_cos (obj 'value)))
		   'tan              (lambda (obj) (#_tan (obj 'value)))
		   'asin             (lambda (obj) (#_asin (obj 'value)))
		   'acos             (lambda (obj) (#_acos (obj 'value)))
		   'atan             (make-method #_atan (lambda (obj) (obj 'value)))
		   'sinh             (lambda (obj) (#_sinh (obj 'value)))
		   'cosh             (lambda (obj) (#_cosh (obj 'value)))
		   'tanh             (lambda (obj) (#_tanh (obj 'value)))
		   'asinh            (lambda (obj) (#_asinh (obj 'value)))
		   'acosh            (lambda (obj) (#_acosh (obj 'value)))
		   'atanh            (lambda (obj) (#_atanh (obj 'value)))
		   'sqrt             (lambda (obj) (#_sqrt (obj 'value)))
		   'expt             (make-method #_expt (lambda (obj) (obj 'value)))
		   'floor            (lambda (obj) (#_floor (obj 'value)))
		   'ceiling          (lambda (obj) (#_ceiling (obj 'value)))
		   'truncate         (lambda (obj) (#_truncate (obj 'value)))
		   'round            (lambda (obj) (#_round (obj 'value)))
		   'integer->char    (lambda (obj) (#_integer->char (obj 'value)))
		   'inexact->exact   (lambda (obj) (#_inexact->exact (obj 'value)))
		   'exact->inexact   (lambda (obj) (#_exact->inexact (obj 'value)))
		   'integer-length   (lambda (obj) (#_integer-length (obj 'value)))
		   'integer-decode-float (lambda (obj) (#_integer-decode-float (obj 'value)))
		   'number?          (lambda (obj) (#_number? (obj 'value))) ; why not #t? currently (mock-number (mock-number ...)) is an error
		   'integer?         (lambda (obj) (#_integer? (obj 'value)))
		   'real?            (lambda (obj) (#_real? (obj 'value)))
		   'complex?         (lambda (obj) (#_complex? (obj 'value)))
		   'rational?        (lambda (obj) (#_rational? (obj 'value)))
		   'exact?           (lambda (obj) (#_exact? (obj 'value)))
		   'inexact?         (lambda (obj) (#_inexact? (obj 'value)))
		   'ash              (make-method #_ash (lambda (obj) (obj 'value)))
		   'logbit?          (make-method #_logbit? (lambda (obj) (obj 'value)))
		   'number->string   (make-method #_number->string (lambda (obj) (obj 'value)))
		   'random           (make-method #_random (lambda (obj) (obj 'value)))
		   'quotient         (make-method #_quotient (lambda (obj) (obj 'value)))
		   'remainder        (make-method #_remainder (lambda (obj) (obj 'value)))
		   'modulo           (make-method #_modulo (lambda (obj) (obj 'value)))
		   'lognot           (lambda (obj) (#_lognot (obj 'value)))
		   'logior           (make-method #_logior (lambda (obj) (obj 'value)))
		   'logxor           (make-method #_logxor (lambda (obj) (obj 'value)))
		   'logand           (make-method #_logand (lambda (obj) (obj 'value)))
		   ;; any object that has lcm or gcd also needs rational?
		   'lcm              (make-method #_lcm (lambda (obj) (obj 'value)))
		   'gcd              (make-method #_gcd (lambda (obj) (obj 'value)))
		   '+                (make-method #_+ (lambda (obj) (obj 'value)))
		   '-                (make-method #_- (lambda (obj) (obj 'value)))
		   '*                (make-method #_* (lambda (obj) (obj 'value)))
		   '/                (make-method #_/ (lambda (obj) (obj 'value)))
		   ;; any object that has min or max also needs real?
		   'max              (make-method #_max (lambda (obj) (obj 'value)))
		   'min              (make-method #_min (lambda (obj) (obj 'value)))
		   '=                (make-method #_= (lambda (obj) (obj 'value)))
		   '<                (make-method #_< (lambda (obj) (obj 'value)))
		   '>                (make-method #_> (lambda (obj) (obj 'value)))
		   '<=               (make-method #_<= (lambda (obj) (obj 'value)))
		   '>=               (make-method #_>= (lambda (obj) (obj 'value)))
		   'write-byte       (lambda (byte . port) (apply #_write-byte (byte 'value) port))

		   'make-list        (lambda (ind . args) (apply #_make-list (ind 'value) args))
		   'make-vector      (make-method #_make-vector (lambda (obj) (obj 'value)))
		   'make-float-vector(make-method #_make-float-vector (lambda (obj) (obj 'value)))
		   'make-hash-table  (lambda (ind . args) (apply #_make-hash-table (ind 'value) args))
		   'make-bytevector  (make-method #_make-bytevector (lambda (obj) (obj 'value)))

		   'bytevector       (make-method #_bytevector (lambda (obj) (obj 'value)))
		   'format           (make-method #_format (lambda (obj) (obj 'value)))

		   'make-string      (lambda (ind . args) 
				       (if (mock-number? ind)
					   (apply #_make-string (ind 'value) args)
					   (error 'wrong-type-arg "make-string ~S ~S" ind args)))
		   
		   'string-ref       (lambda (str ind) 
				       (if (string? str)
					   (#_string-ref str (ind 'value))
					   (error 'wrong-type-arg "make-string ~S ~S" str ind)))

		   'string-set!      (lambda (str ind val) 
				       (if (string? str)
					   (#_string-set! str (ind 'value) val)
					   (error 'wrong-type-arg "string-set! ~S ~S ~S" str ind val)))

		   'string->number   (lambda (str radix) 
				       (if (string? str)
					   (#_string->number str (radix 'value))
					   (error 'wrong-type-arg "string->number ~S ~S" str radix)))

		   'list-ref         (lambda (lst ind) 
				       (if (pair? lst)
					   (#_list-ref lst (ind 'value))
					   (error 'wrong-type-arg "list-ref ~S ~S" lst ind)))

		   'list-set!        (lambda (lst ind val)
				       (if (pair? lst)
					   (#_list-set! lst (ind 'value) val)
					   (error 'wrong-type-arg "list-set! ~S ~S ~S" lst ind val)))

		   'list-tail        (lambda (lst ind) 
				       (if (pair? lst)
					   (#_list-tail lst (ind 'value))
					   (error 'wrong-type-arg "list-tail ~S ~S" ind args)))

		   'vector-ref       (lambda (vec ind) 
				       (if (vector? vec)
					   (#_vector-ref vec (ind 'value))
					   (error 'wrong-type-arg "vector-ref ~S ~S" vec ind)))

		   'vector-set!      (lambda (vec ind val) 
				       (if (vector? vec)
					   (#_vector-set! vec (ind 'value) val)
					   (error 'wrong-type-arg "vector-set! ~S ~S ~S" vec ind val)))

		   'make-shared-vector (lambda (obj dims offset) 
					 (if (and (vector? obj)
						  (pair? dims))
					     (#_make-shared-vector obj dims (offset 'value))
					     (error 'wrong-type-arg "make-shared-vector ~S ~S ~S" obj dims offset)))
		   
		   'vector->list     (lambda* (vec start end) 
				       (if (vector? vec)
					   ;; when there are two args, either might have triggered this method call,
					   ;;   if (not (let? end)) or (let? start), start must be a mock-number
					   ;;   and if (not (let? start)), end must be a mock-number, but
					   ;;   if (let? start) and (let? end), end might be anything
					   (range-method-1 #_vector->list vec start end)
					   (error 'wrong-type-arg "vector->list ~S ~S ~S" vec start end)))

		   'vector-fill!     (lambda* (vec c start end)
				       (if (vector? vec)
					   (range-method-2 #_vector-fill! vec c start end)
					   (error 'wrong-type-arg "vector-fill! ~S ~S ~S ~S" vec c start end)))

		   'substring        (lambda* (str start end) 
				       (if (string? str)
					   (range-method-1 #_substring start end)
					   (error 'wrong-type-arg "substring ~S ~S ~S" str start end)))

		   'string-fill!     (lambda* (str c start end)
				       (if (and (string? str)
						(char? c))
					   (range-method-2 #_string-fill! str c start end)
					   (error 'wrong-type-arg "string-fill! ~S ~S ~S ~S" str c start end)))

		   'string->list     (lambda* (str start end) 
				       (if (string? str)
					   (range-method-1 #_string->list str start end)
					   (error 'wrong-type-arg "string->list ~S ~S ~S" str start end)))

		   'write-string     (lambda* (str port start end)
				       (if (and (string? str)
						(output-port? port))
					   (range-method-2 #_write-string str port start end)
					   (error 'wrong-type-arg "write-string ~S ~S ~S ~S" str port start end)))

		   'read-string     (lambda* (k (port (current-input-port)))
				      (#_read-string (k 'value) port))

		   'copy             (lambda* (obj dest start end)
				       (if (mock-number? obj)
					   (obj 'value)
					   (if (or (mock-number? start)
						   (mock-number? end))
					       (range-method-2 #_copy obj dest start end)
					       (error 'wrong-type-arg "copy ~S ~S ~S ~S" obj dest start end))))

		   'length           (lambda (obj) #f)
		   'number?          (lambda (obj) #t)
		   'values           (lambda (obj . args) (obj 'value))
		   'class-name       'mock-number))))
      
      (define (mock-number x)
	(if (and (number? x)
		 (not (let? x)))
	    (openlet
	     (sublet (*mock-number* 'mock-number-class)
	       'value x
	       'object->string mock->string))
	    (error 'wrong-type-arg "mock-number ~S is not a number" x)))
      
      (set! mock-number? (lambda (obj)
			   (and (openlet? obj)
				(outlet-member obj mock-number-class))))
      
      (curlet))))


#|
;;; fuzzy number

(define fuzzy-number
  (let ((fuzz (lambda (fx)
		(#_* fx (#_- 1.05 (#_random .1))))))
    (lambda (fx)
      (openlet 
       (sublet 
	   (*mock-number* 'mock-number-class)
	 'let-ref-fallback (lambda (obj sym) (fuzz fx))
	 'object->string (lambda (obj . args) (#_number->string (fuzz fx))))))))


;;; interval arithmetic 
;;; 
;;; from Wikipedia:
;;; x + y =	[a+c, b+d]
;;; x - y =	[a-d, b-c]
;;; x × y =	[min(ac, ad, bc, bd), max(ac, ad, bc, bd)]
;;; x / y =	[min(a/c, a/d, b/c, b/d), max(a/c, a/d, b/c, b/d)]

(define *interval*
  (let* ((make-interval #f)
	 (low (lambda (z) (z 'low)))
	 (high (lambda (z) (z 'high)))
	 (interval-class 
	  (openlet (sublet (*mock-number* 'mock-number-class)

		     '+ (lambda args
			  (let ((lo 0)
				(hi 0))
			    (for-each
			     (lambda (z)
			       (if (let? z)
				   (begin
				     (set! lo (+ lo (low z)))
				     (set! hi (+ hi (high z))))
				   (begin
				     (set! lo (+ lo z))
				     (set! hi (+ hi z)))))
			     args)
			    (make-interval lo hi)))
		     
		     '* (lambda args
			  (let ((lo 1)
				(hi 1))
			    (for-each
			     (lambda (z)
			       (let ((zlo (if (let? z) (low z) z))
				     (zhi (if (let? z) (high z) z)))
				 (let ((ac (* lo zlo))
				       (ad (* lo zhi))
				       (bc (* hi zlo))
				       (bd (* hi zhi)))
				   (set! lo (min ac ad bc bd))
				   (set! hi (max ac ad bc bd)))))
			     args)
			    (make-interval lo hi)))
		     
		     '- (lambda args
			  (let ((z (car args)))
			    (if (null? (cdr args)) ; negate (must be let? else how did we get here?)
				(make-interval (- (high z)) (- (low z)))
				(let ((lo (low z))
				      (hi (high z)))
				  (for-each
				   (lambda (z)
				     (if (let? z)
					 (begin
					   (set! lo (- lo (high z)))
					   (set! hi (- hi (low z))))
					 (begin
					   (set! lo (- lo z))
					   (set! hi (- hi z)))))
				   (cdr args))
				  (make-interval lo hi)))))
			  
		     '/ (lambda args
			  (let ((z (car args)))
			    (if (null? (cdr args)) ; invert
				(make-interval (/ (high z)) (/ (low z)))
				(let ((lo (low z))
				      (hi (high z)))
				  (for-each
				   (lambda (z)
				     (let ((zlo (if (let? z) (low z) z))
					   (zhi (if (let? z) (high z) z)))
				       (let ((ac (/ lo zlo))
					     (ad (/ lo zhi))
					     (bc (/ hi zlo))
					     (bd (/ hi zhi)))
					 (set! lo (min ac ad bc bd))
					 (set! hi (max ac ad bc bd)))))
				   (cdr args))
				  (make-interval lo hi)))))

		     'abs (lambda (z)
			    (if (positive? (low z))
				(make-interval (low z) (high z))
				(if (negative? (high z))
				    (make-interval (abs (high z)) (abs (low z)))
				    (make-interval 0 (max (abs (low z)) (abs (high z)))))))
			  
		     'object->string (lambda (obj . args) 
				       (format #f "#<interval: ~S ~S>" (low obj) (high obj)))
		     ))))
    
    (set! make-interval (lambda (low high)
			  (if (> low high) (format *stderr* "~A ~A~%" low high))
			  (openlet (sublet interval-class 'low low 'high high))))

    (curlet)))

(define x ((*interval* 'make-interval) 3.0 4.0))
|#



;;; --------------------------------------------------------------------------------

(define *mock-pair*
  (let ((mock-pair? #f))
    (let ((mock-pair-class
	   (openlet
	    (inlet 'morally-equal?   (lambda (x y) (#_morally-equal? (x 'value) y))
		   'pair-line-number (lambda (obj) (#_pair-line-number (obj 'value)))
		   'list->string     (lambda (obj) (#_list->string (obj 'value)))
		   'object->string   (lambda (obj . arg) "#<mock-pair-class>")
		   'list?            (lambda (obj) (#_list? (obj 'value)))
		   'car              (lambda (obj) (#_car (obj 'value)))
		   'cdr              (lambda (obj) (#_cdr (obj 'value)))
		   'set-car!         (lambda (obj val) (#_set-car! (obj 'value) val))
		   'set-cdr!         (lambda (obj val) (#_set-cdr! (obj 'value) val))
		   'caar             (lambda (obj) (#_caar (obj 'value)))
		   'cadr             (lambda (obj) (#_cadr (obj 'value)))
		   'cdar             (lambda (obj) (#_cdar (obj 'value)))
		   'cddr             (lambda (obj) (#_cddr (obj 'value)))
		   'caaar            (lambda (obj) (#_caaar (obj 'value)))
		   'caadr            (lambda (obj) (#_caadr (obj 'value)))
		   'cadar            (lambda (obj) (#_cadar (obj 'value)))
		   'cdaar            (lambda (obj) (#_cdaar (obj 'value)))
		   'caddr            (lambda (obj) (#_caddr (obj 'value)))
		   'cdddr            (lambda (obj) (#_cdddr (obj 'value)))
		   'cdadr            (lambda (obj) (#_cdadr (obj 'value)))
		   'cddar            (lambda (obj) (#_cddar (obj 'value)))
		   'caaaar           (lambda (obj) (#_caaaar (obj 'value)))
		   'caaadr           (lambda (obj) (#_caaadr (obj 'value)))
		   'caadar           (lambda (obj) (#_caadar (obj 'value)))
		   'cadaar           (lambda (obj) (#_cadaar (obj 'value)))
		   'caaddr           (lambda (obj) (#_caaddr (obj 'value)))
		   'cadddr           (lambda (obj) (#_cadddr (obj 'value)))
		   'cadadr           (lambda (obj) (#_cadadr (obj 'value)))
		   'caddar           (lambda (obj) (#_caddar (obj 'value)))
		   'cdaaar           (lambda (obj) (#_cdaaar (obj 'value)))
		   'cdaadr           (lambda (obj) (#_cdaadr (obj 'value)))
		   'cdadar           (lambda (obj) (#_cdadar (obj 'value)))
		   'cddaar           (lambda (obj) (#_cddaar (obj 'value)))
		   'cdaddr           (lambda (obj) (#_cdaddr (obj 'value)))
		   'cddddr           (lambda (obj) (#_cddddr (obj 'value)))
		   'cddadr           (lambda (obj) (#_cddadr (obj 'value)))
		   'cdddar           (lambda (obj) (#_cdddar (obj 'value)))
		   'assq             (lambda (val obj) (#_assq val (obj 'value)))
		   'assv             (lambda (val obj) (#_assv val (obj 'value)))
		   'assoc            (lambda (val obj . args) (apply #_assoc val (obj 'value) args))
		   'memq             (lambda (val obj) (#_memq val (obj 'value)))
		   'memv             (lambda (val obj) (#_memv val (obj 'value)))
		   'member           (lambda (val obj . args) (apply #_member val (obj 'value) args))
		   'let-ref          (lambda (obj ind) (coverlet obj) (let ((val (#_list-ref (obj 'value) ind))) (openlet obj) val))
		   'let-set!         (lambda (obj ind val) (coverlet obj) (#_list-set! (obj 'value) ind val) (openlet obj) val)
		   'arity            (lambda (obj) (#_arity (obj 'value)))
		   'fill!            (lambda (obj val) (#_fill! (obj 'value) val))
		   'reverse          (lambda (obj) (#_reverse (obj 'value)))
		   'reverse!         (lambda (obj) (set! (obj 'value) (#_reverse (obj 'value))))
		   'sort!            (lambda (obj f) (#_sort! (obj 'value) f))
		   'for-each         (lambda (f obj) (#_for-each f (obj 'value)))
		   'map              (lambda (f obj) (#_map f (obj 'value)))
		   'eval             (lambda (f obj) (#_eval (obj 'value)))
		   'list->vector     (lambda (obj) (#_list->vector (obj 'value)))

		   'list-tail        (lambda (obj . args) 
				       (if (mock-pair? obj)
					   (apply #_list-tail (obj 'value) args)
					   (error 'wrong-type-arg "list-tail ~S ~S" obj args)))

		   'copy             (lambda (obj . args) 
				       (if (mock-pair? obj)
					   (apply #_copy (obj 'value) args)
					   (error 'wrong-type-arg "copy ~S ~S" obj args)))
		   
		   'make-shared-vector (lambda (obj dims . args) 
					 (if (mock-pair? dims)
					     (apply #_make-shared-vector obj (dims 'value) args)
					     (error 'wrong-type-arg "make-shared-vector ~S ~S ~S" obj dims args)))

		   'make-vector      (lambda (obj dims . args) 
				       (if (mock-pair? dims)
					   (apply #_make-vector obj (dims 'value) args)
					   (error 'wrong-type-arg "make-vector ~S ~S ~S" obj dims args)))

		   'append           (make-method #_append (lambda (obj) (obj 'value)))

		   'list-ref         (lambda (obj ind) 
				       (if (mock-pair? obj)
					   (#_list-ref (obj 'value) ind)
					   (error 'wrong-type-arg "list-ref ~S ~S" obj ind)))

		   'list-set!        (lambda (obj ind val) 
				       (if (mock-pair? obj)
					   (#_list-set! (obj 'value) ind val)
					   (error 'wrong-type-arg "list-set! ~S ~S ~S" obj ind val)))

		   'pair?            (lambda (obj) #t)
		   'length           (lambda (obj) (#_length (obj 'value)))
		   'values           (lambda (obj . args) (obj 'value))
		   'class-name       'mock-pair))))
      
      (define (mock-pair . args)
	(openlet
	 (sublet (*mock-pair* 'mock-pair-class)
	   'value (copy args)
	   'object->string mock->string)))
      
      (set! mock-pair? (lambda (obj)
			 (and (openlet? obj)
			      (outlet-member obj mock-pair-class))))
      
      (curlet))))

#|
(let ((immutable-list-class 
       (sublet (*mock-pair* 'mock-pair-class)
	 'object->string   mock->string

	 'let-set!         (lambda (obj i val) 
			     (set! (obj 'value) (append (copy (obj 'value) (make-list (+ i 1))) (list-tail (obj 'value) (+ i 1))))
			     (list-set! (obj 'value) i val))
	 'list-set!        (lambda (obj i val) 
			     (set! (obj 'value) (append (copy (obj 'value) (make-list (+ i 1))) (list-tail (obj 'value) (+ i 1))))
			     (list-set! (obj 'value) i val))
	 'set-car!         (lambda (obj val) 
			     (set! (obj 'value) (cons val (cdr (obj 'value)))))
	 'set-cdr!         (lambda (obj val) 
			     (set! (obj 'value) (cons (car (obj 'value)) val)))
	 'fill!            (lambda (obj val) 
			     (set! (obj 'value) (fill! (copy (obj 'value)) val)))
	 'reverse!         (lambda (obj) 
			     (set! (obj 'value) (reverse (obj 'value))))
	 'sort!            (lambda (obj func) 
			     (set! (obj 'value) (sort! (copy (obj 'value)) func))))))

    (define (immutable-list lst)
      (openlet 
       (sublet immutable-list-class
	 'value lst))))
|#

;;; since a mock-pair prints itself as if a list, you can get some strange printout results:
;;;    (cons 'a ((*mock-pair* 'mock-pair) 'b 'c)) -> '(a . (b c))



;;; --------------------------------------------------------------------------------

(define *mock-symbol*
  (let ((mock-symbol-class
	 (openlet
	  (inlet 'object->string        (lambda (obj . arg) "#<mock-symbol-class>")
		 'morally-equal?        (lambda (x y) (#_morally-equal? (x 'value) y))
		 'gensym?               (lambda (obj) (#_gensym? (obj 'value)))
		 'symbol->string        (lambda (obj) (#_symbol->string (obj 'value)))
		 'symbol->value         (lambda (obj . args) (apply #_symbol->value (obj 'value) args))
		 'symbol->dynamic-value (lambda (obj) (#_symbol->dynamic-value (obj 'value)))
		 'symbol-access         (lambda (obj . args) (apply #_symbol-access (obj 'value) args))
		 'provided?             (lambda (obj) (#_provided? (obj 'value)))
		 'provide               (lambda (obj) (#_provide (obj 'value)))
		 'defined?              (lambda (obj) (#_defined? (obj 'value)))
		 'symbol->keyword       (lambda (obj) (#_symbol->keyword (obj 'value)))
		 'keyword?              (lambda (obj) (#_keyword? (obj 'value)))
		 'keyword->symbol       (lambda (obj) (#_keyword->symbol (obj 'value)))
		 'format                (lambda (str s . args) (#_symbol->string s))
		 'symbol?               (lambda (obj) #t)
		 'class-name            'mock-symbol
		 'values                (lambda (obj . args) (obj 'value))
		 ))))

    (define (mock-symbol s)
      (if (and (symbol? s)
	       (not (let? s)))
	  (openlet
	   (sublet (*mock-symbol* 'mock-symbol-class)
	     'value s
	     'object->string mock->string))
	  (error 'wrong-type-arg "mock-symbol ~S is not a symbol" s)))
    
    (define (mock-symbol? obj)
      (and (openlet? obj)
	   (outlet-member obj mock-symbol-class)))

    (curlet)))


;;; --------------------------------------------------------------------------------

(define *mock-port*
  (let ((mock-port? #f))
    (let ((mock-port-class
	   (openlet
	    (inlet 'port?               (lambda (obj) #t)
		   'morally-equal?      (lambda (x y) (#_morally-equal? (x 'value) y))
		   'close-input-port    (lambda (obj) (#_close-input-port (obj 'value)))
		   'close-output-port   (lambda (obj) (#_close-output-port (obj 'value)))
		   'flush-output-port   (lambda (obj) (#_flush-output-port (obj 'value)))
		   'get-output-string   (lambda (obj) (#_get-output-string (obj 'value)))
		   'newline             (lambda (obj) (#_newline (obj 'value)))
		   'write               (lambda (x obj) (#_write x (obj 'value)))
		   'display             (lambda (x obj) (#_display x (obj 'value)))
		   'read-char           (lambda (obj) (#_read-char (obj 'value)))
		   'peek-char           (lambda (obj) (#_peek-char (obj 'value)))
		   'read-byte           (lambda (obj) (#_read-byte (obj 'value)))
		   'read-line           (lambda (obj . args) (apply #_read-line (obj 'value) args))
		   'read                (lambda (obj) (#_read (obj 'value)))
		   'input-port?         (lambda (obj) (#_input-port? (obj 'value)))
		   'output-port?        (lambda (obj) (#_output-port? (obj 'value)))
		   'port-closed?        (lambda (obj) (#_port-closed? (obj 'value)))
		   'char-ready?         (lambda (obj) (#_char-ready? (obj 'value)))
		   'port-line-number    (lambda (obj) (#_port-line-number (obj 'value)))
		   'port-filename       (lambda (obj) (#_port-filename (obj 'value)))
		   'object->string      (lambda (obj . args) "#<mock-port-class>")
		   'format              (make-method #_format (lambda (obj) (obj 'value)))

		   'set-current-output-port (lambda (obj) (#_set-current-output-port (obj 'value)))
		   'set-current-input-port  (lambda (obj) (#_set-current-input-port (obj 'value)))
		   'set-current-error-port  (lambda (obj) (#_set-current-error-port (obj 'value)))
		   
		   'write-char          (lambda (c obj) 
					  (if (mock-port? obj)
					      (#_write-char c (obj 'value))
					      (error 'wrong-type-arg "write-char ~S ~S" c obj)))

		   'write-string        (lambda (s obj . args) 
					  (if (mock-port? obj)
					      (apply #_write-string s (obj 'value) args)
					      (error 'wrong-type-arg "write-string ~S ~S ~S" s obj args)))

		   'write-byte          (lambda (b obj) 
					  (if (mock-port? obj)
					      (#_write-byte b (obj 'value))
					      (error 'wrong-type-arg "write-byte ~S ~S" b obj)))
		   
		   'read-string         (lambda (k obj) 
					  (if (mock-port? obj)
					      (#_read-string k (obj 'value))
					      (error 'wrong-type-arg "read-string ~S ~S" k obj)))
		   'values              (lambda (obj . args) (obj 'value))
		   'class-name          'mock-port
		   ))))
      
      (define (mock-port port)
	(if (and (or (input-port? port)
		     (output-port? port))
		 (not (let? port)))
	    (openlet
	     (sublet (*mock-port* 'mock-port-class)
	       'value port
	       'object->string mock->string))
	    (error 'wrong-type-arg "mock-port ~S is not a port" port)))
      
      (set! mock-port? (lambda (obj)
			 (and (openlet? obj)
			      (outlet-member obj mock-port-class))))
      
      (curlet))))

;;; sublet of any of these needs to include the value field or a let-ref-fallback
#|
(require libc.scm)

(define *input-file*
  (let ((file-write-date (lambda (file)
			   (with-let (sublet *libc* :file file)
			     (let ((buf (stat.make)))
			       (stat file buf)
			       (let ((date (stat.st_mtime buf)))
				 (free buf)
				 date)))))
	(file-size (lambda (file)
		      (with-let (sublet *libc* :file file)
			(let ((buf (stat.make)))
			  (stat file buf)
			  (let ((size (stat.st_size buf)))
			    (free buf)
			    size)))))
	(file-owner (lambda (file)
		      (with-let (sublet *libc* :file file)
			(let ((buf (stat.make)))
			  (stat file buf)
			  (let ((uid (stat.st_uid buf)))
			    (free buf)
			    (let ((pwd (getpwuid uid)))
			      (passwd.pw_name pwd))))))))
    (openlet
     (sublet (*mock-port* 'mock-port-class)
       'value      #f
       'length     (lambda (obj) (file-size (obj 'file-name)))
       'owner      (lambda (obj) (file-owner (obj 'file-name)))
       'write-date (lambda (obj) (file-write-date (obj 'file-name)))))))

(define (open-a-file file)
  (let ((p (openlet
	    (sublet *input-file* 
	      'file-name file))))
    (set! (p 'value) (open-input-file "oboe.snd"))
    p))

(define p (open-a-file "oboe.snd"))
(length p) -> 101684
((p 'owner) p) -> "bil"
|#

