anchor.diff:  (defun type-number-of (object)
     (find-type-number (type-of object)))
   
  -
  -
  -;;;; Superclass for all metaclasses implementing some sort of virtual slots
  +(defun alien-function (name return-type &rest arg-types)
  +  (let ((alien
  +	 (alien::%heap-alien
  +	  (alien::make-heap-alien-info
  +	   :type (alien::parse-alien-type
  +		  `(function ,@(cons return-type arg-types)))
  +	   :sap-form (system:foreign-symbol-address name)))))
  +    #'(lambda (&rest args)
  +	(apply #'alien:alien-funcall alien args))))
  +
  +
  +(defun type-init (name &optional init-fname)
  +  (funcall
  +   (alien-function
  +    (or
  +     init-fname
  +     (default-alien-fname (format nil "~A_get_type" name)))
  +    '(unsigned 32))))
  +
  +
  +;;;; Superclass for wrapping types in the glib type system
   
   (eval-when (:compile-toplevel :load-toplevel :execute)
  -  (defclass virtual-class (pcl::standard-class))
  -
  -  (defclass direct-virtual-slot-definition (standard-direct-slot-definition)
  -    ((location
  -      :reader slot-definition-location
  -      :initarg :location)))
  -  
  -  (defclass effective-virtual-slot-definition
  -    (standard-effective-slot-definition)))
  -  
  -
  -(defmethod direct-slot-definition-class ((class virtual-class) initargs)
  -  (if (eq (getf initargs :allocation) :virtual)
  -      (find-class 'direct-virtual-slot-definition)
  -    (call-next-method)))
  -
  -
  -(defmethod effective-slot-definition-class ((class virtual-class) initargs)
  -  (if (eq (getf initargs :allocation) :virtual)
  -      (find-class 'effective-virtual-slot-definition)
  -    (call-next-method)))
  -
  -
  -(defun %direct-slot-definitions-slot-value (slotds slot &optional default)
  -  (let ((slotd
  -	 (find-if
  -	  #'(lambda (slotd)
  -	      (and
  -	       (slot-exists-p slotd slot)
  -	       (slot-boundp slotd slot)))
  -	  slotds)))
  -    (if slotd
  -	(slot-value slotd slot)
  -      default)))
  -  
  -
  -(defgeneric compute-virtual-slot-location (class slotd direct-slotds))
  -
  -(defmethod compute-virtual-slot-location
  -    ((class virtual-class)
  -     (slotd effective-virtual-slot-definition)
  -     direct-slotds)
  -    (let ((location
  -	   (%direct-slot-definitions-slot-value direct-slotds 'location)))
  -      (if (and location (symbolp location))
  -	  (list location `(setf ,location))
  -	location)))
  -
  -
  -(defmethod compute-effective-slot-definition
  -    ((class virtual-class) direct-slotds)
  -  (let ((slotd (call-next-method)))
  -    (when (typep slotd 'effective-virtual-slot-definition)
  -      (setf
  -       (slot-value slotd 'pcl::location)
  -       (compute-virtual-slot-location class slotd direct-slotds)))
  -    slotd))
  -
  -
  -(defmethod slot-value-using-class
  -    ((class virtual-class) (object standard-object)
  -     (slotd effective-virtual-slot-definition))
  -  (let ((reader (first (slot-definition-location slotd))))
  -    (if reader
  -	(funcall reader object)
  -      (slot-unbound class object (slot-definition-name slotd)))))
  -
  -
  -(defmethod slot-boundp-using-class
  -    ((class virtual-class) (object standard-object)
  -     (slotd effective-virtual-slot-definition))
  -   (and (first (slot-definition-location slotd)) t))
  -    
  -
  -
  -(defmethod (setf slot-value-using-class)
  -    (value (class virtual-class) (object standard-object)
  -     (slotd effective-virtual-slot-definition))
  -  (let ((writer (second (slot-definition-location slotd))))
  -    (cond
  -     ((null writer)
  -      (error
  -       "Can't set read-only slot ~A in ~A"
  -       (slot-definition-name slotd)
  -       object))
  -     ((or (functionp writer) (symbolp writer))
  -      (funcall writer value object)
  -      value)
  -     (t
  -      (funcall (fdefinition writer) value object)
  -      value))))
  -	
  -
  -(defmethod validate-superclass
  -    ((class virtual-class) (super pcl::standard-class))
  -  t)
  -
  -
  -
  -;;;; Superclass for wrapping of C structures
  -
  -(eval-when (:compile-toplevel :load-toplevel :execute)
  -  (defclass alien-instance ()
  -    ((location
  -      :reader alien-instance-location
  -      :type system-area-pointer)))
  -
  -  (defgeneric allocate-alien-storage (class))
  -  (defgeneric reference-instance (object))
  -  (defgeneric unreference-instance (object))
  -  (defgeneric from-alien-initialize-instance (object &rest initargs))
  -  (defgeneric instance-finalizer (object)))
  -
  -
  -(internal *instance-cache*)
  -(defvar *instance-cache* (make-hash-table :test #'eql))
  -
  -(defun cache-instance (object)
  -  (setf
  -   (gethash (system:sap-int (alien-instance-location object)) *instance-cache*)
  -   (ext:make-weak-pointer object)))
  -
  -(defun find-cached-instance (location)
  -  (let ((ref (gethash (system:sap-int location) *instance-cache*)))
  -    (when ref
  -      (ext:weak-pointer-value ref))))
  -
  -(defun remove-cached-instance (location)
  -  (remhash (system:sap-int location) *instance-cache*))
  -
  -
  -(defmethod initialize-instance :before ((instance alien-instance)
  -					&rest initargs &key)
  +  (defclass ginstance (proxy)
  +    ()
  +    (:metaclass proxy-class)
  +    (:size 4 #|(size-of 'pointer|#)))
  +
  +(defmethod initialize-proxy ((instance ginstance) &rest initargs &key location)
     (declare (ignore initargs))
  -  (setf
  +  (setf 
      (slot-value instance 'location)
  -   (allocate-alien-storage (class-of instance)))
  -  (cache-instance instance)
  -  (ext:finalize instance (instance-finalizer instance)))
  -
  -
  -(defmethod from-alien-initialize-instance ((instance alien-instance)
  -					   &rest initargs &key location)
  -  (declare (ignore initargs))
  -  (setf (slot-value instance 'location) location)
  -  (cache-instance instance))
  -
  -
  -(deftype-method translate-type-spec alien-instance (type-spec)
  +   (funcall (ginstance-class-ref (class-of instance)) location))
  +  (call-next-method))
  +
  +(defmethod instance-finalizer ((instance ginstance))
  +  (let ((location (proxy-location instance))
  +	(unref (ginstance-class-unref (class-of instance))))
  +    (declare (type system-area-pointer location))
  +    #'(lambda ()
  +	(funcall unref location)
  +	(remove-cached-instance location))))
  +
  +(defun %type-of-ginstance (location)
  +  (let ((class (sap-ref-sap location 0)))
  +    (type-from-number (sap-ref-unsigned class 0))))
  +
  +(deftype-method translate-from-alien
  +    ginstance (type-spec location &optional weak-ref)
     (declare (ignore type-spec))
  -  (translate-type-spec 'pointer))
  -
  -(deftype-method size-of alien-instance (type-spec)
  -  (declare (ignore type-spec))
  -  (size-of 'pointer))
  -
  -
  -
  -;;;; Metaclass used for subclasses of alien-instance
  -
  -(eval-when (:compile-toplevel :load-toplevel :execute)
  -  (defclass alien-class (virtual-class)
  -    ((size
  -      :reader alien-class-size)))
  -
  -  (defclass direct-alien-slot-definition (direct-virtual-slot-definition)
  -    ((allocation
  -      :initform :alien)
  -     (offset
  -      :reader slot-definition-offset
  -      :initarg :offset
  -      :initform 0)))
  -  
  -  (defclass effective-alien-slot-definition (effective-virtual-slot-definition)
  -    ((offset
  -      :reader slot-definition-offset)))
  -  
  -  (defclass effective-virtual-alien-slot-definition
  -    (effective-virtual-slot-definition))
  - 
  -
  -  (defmethod alien-class-superclass ((class alien-class))
  -    (find-if
  -     #'(lambda (class)
  -	 (subtypep (class-name class) 'alien-instance))
  -     (pcl::class-direct-superclasses class)))
  -
  -
  -  (defmethod shared-initialize ((class alien-class) names
  -				&rest initargs &key size alien-name name)
  -    (declare (ignore initargs))
  -    (call-next-method)
  -
  -    (when alien-name
  -      (setf (alien-type-name (or name (class-name class))) (first alien-name)))
  -    (when size
  -      (setf (slot-value class 'size) (first size))))
  -    
  -
  -  (defmethod shared-initialize :after ((class alien-class) names
  -				       &rest initargs &key)
  -    (declare (ignore initargs names))
  -    (let* ((super (alien-class-superclass class))
  -	   (actual-size
  -	    (if (eq (class-name super) 'alien-instance)
  -		0
  -	      (alien-class-size super))))
  -      (dolist (slotd (class-slots class))
  -	(when (eq (slot-definition-allocation slotd) :alien)
  -	  (with-slots (offset type) slotd
  -	    (setq actual-size (max actual-size (+ offset (size-of type)))))))
  -      (cond
  -       ((not (slot-boundp class 'size))
  -	(setf (slot-value class 'size) actual-size))
  -       ((> actual-size (slot-value class 'size))
  -	(warn "The actual size of class ~A is lager than specified" class)))))
  -
  -
  -  (defmethod direct-slot-definition-class ((class alien-class) initargs)
  -    (case (getf initargs :allocation)
  -      ((nil :alien) (find-class 'direct-alien-slot-definition))
  -;      (:instance (error "Allocation :instance not allowed in class ~A" class))
  -      (t (call-next-method))))
  -
  -
  -  (defmethod effective-slot-definition-class ((class alien-class) initargs)
  -    (case (getf initargs :allocation)
  -      (:alien (find-class 'effective-alien-slot-definition))
  -      (:virtual (find-class 'effective-virtual-alien-slot-definition))
  -      (t (call-next-method))))
  -  
  -  
  -  (defmethod compute-virtual-slot-location
  -      ((class alien-class) (slotd effective-alien-slot-definition)
  -       direct-slotds)
  -    (with-slots (offset type) slotd
  -      (setf offset (%direct-slot-definitions-slot-value direct-slotds 'offset))
  -      (let ((reader (get-reader-function type))
  -	    (writer (get-writer-function type))
  -	    (destroy (get-destroy-function type)))
  -	(list
  -	 #'(lambda (object)
  -	     (funcall reader (alien-instance-location object) offset))
  -	 #'(lambda (value object)
  -	     (let ((location (alien-instance-location object)))
  -	       (funcall destroy location offset)
  -	       (funcall writer value location offset)))))))
  -	     
  -  
  -  (defmethod compute-virtual-slot-location
  -      ((class alien-class)
  -       (slotd effective-virtual-alien-slot-definition)
  -       direct-slotds)
  -    (let ((location (call-next-method)))
  -      (if (or (stringp location) (consp location))
  -	  (destructuring-bind (reader &optional writer) (mklist location)
  -	    (with-slots (type) slotd
  -              (list
  -	       (if (stringp reader)
  -		   (let* ((alien-type (translate-type-spec type))
  -			  (alien
  -			   (alien::%heap-alien
  -			    (alien::make-heap-alien-info
  -			     :type (alien::parse-alien-type
  -				    `(function ,alien-type system-area-pointer))
  -			     :sap-form (system:foreign-symbol-address reader))))
  -			  (from-alien (get-from-alien-function type)))
  -		     #'(lambda (object)
  -			 (funcall
  -			  from-alien
  -			  (alien-funcall
  -			   alien (alien-instance-location object)))))
  -		 reader)
  -	       (if (stringp writer)
  -		   (let* ((alien-type (translate-type-spec type))
  -			  (alien
  -			   (alien::%heap-alien
  -			    (alien::make-heap-alien-info
  -			     :type (alien::parse-alien-type
  -				    `(function
  -				      void system-area-pointer ,alien-type))
  -			     :sap-form (system:foreign-symbol-address writer))))
  -			  (to-alien (get-to-alien-function type))
  -			  (cleanup  (get-cleanup-function type)))
  -		     #'(lambda (value object)
  -			 (let ((alien-value (funcall to-alien value))
  -			       (location (alien-instance-location object)))
  -			   (alien-funcall alien location alien-value)
  -			   (funcall cleanup alien-value))))
  -		 writer))))
  -	location)))
  -
  -
  -  (defmethod compute-slots ((class alien-class))
  -    ;; Translating the user supplied relative (to previous slot) offsets
  -    ;; to absolute offsets.
  -    ;; This code is broken and have to be fixed for real use.
  -    (with-slots (direct-slots) class
  -      (let* ((super (alien-class-superclass class))
  -	     (slot-offset
  -	      (if (eq (class-name super) 'alien-instance)
  -		  0
  -		(alien-class-size super))))
  -	(dolist (slotd direct-slots)
  -	  (when (eq (slot-definition-allocation slotd) :alien)
  -	    (with-slots (offset type) slotd
  -	      (setf
  -	       offset (+ slot-offset offset)
  -	       slot-offset (+ offset (size-of type)))))))
  -    
  -      ;; Reverse the direct slot definitions so the effective slots
  -      ;; will be in correct order.
  -      (setf direct-slots (reverse direct-slots))
  -      ;; This nreverse caused me so much frustration that I leave it
  -      ;; here just as a reminder of what not to do.
  -;      (setf direct-slots (nreverse direct-slots))
  -      )
  -    (call-next-method))
  -
  -
  -  (defmethod validate-superclass ((class alien-class)
  -				  (super pcl::standard-class))
  -     (subtypep (class-name super) 'alien-instance))
  -
  -  (defgeneric make-instance-from-alien (class location &rest initargs &key)))
  -
  -(defmethod make-instance-from-alien ((class symbol) location
  -				     &rest initargs &key)
  -  (apply #'make-instance-from-alien (find-class class) location initargs))
  -
  -(defmethod make-instance-from-alien ((class alien-class) location
  -				     &rest initargs &key)
  -  (let ((instance (allocate-instance class)))
  -    (apply
  -     #'from-alien-initialize-instance
  -     instance :location location initargs)
  -    instance))
  -
  -(defun ensure-alien-instance (class location &rest initargs)
  -  (or
  -   (find-cached-instance location)
  -   (apply #'make-instance-from-alien class location initargs)))
  -
  -(defmethod allocate-alien-storage ((class alien-class))
  -  (allocate-memory (alien-class-size class)))
  -
  -
  -
  -;;;; Superclass for wrapping structures with reference counting
  -
  -(eval-when (:compile-toplevel :load-toplevel :execute)
  -  (defclass alien-object (alien-instance)
  -    ()
  -    (:metaclass alien-class)
  -    (:size 0)))
  -
  -(define-type-method-fun alien-ref (type-spec))
  -(define-type-method-fun alien-unref (type-spec))
  -
  -(defmethod from-alien-initialize-instance ((object alien-object)
  -					   &rest initargs &key)
  -  (declare (ignore initargs))
  -  (call-next-method)
  -  (reference-instance object))
  -
  -(defmethod instance-finalizer ((object alien-object))
  -  (let ((location (alien-instance-location object))
  -	(unref (fdefinition (alien-unref (class-of object)))))
  -    (declare (type system-area-pointer location) (type function unref))
  -    #'(lambda ()
  -	(remove-cached-instance location)
  -	(funcall unref location))))
  -
  -(defmethod reference-instance ((object alien-object))
  -  (funcall (alien-ref (class-of object)) object)
  -  object)
  -
  -(defmethod unreference-instance ((object alien-object))
  -  (funcall (alien-unref (class-of object)) object)
  -  nil)
  -
  -(deftype-method translate-to-alien
  -    alien-object (type-spec object &optional copy)
  -  (if copy
  -      `(,(alien-ref type-spec) ,object)
  -    `(alien-instance-location ,object)))
  -
  -(deftype-method translate-from-alien
  -    alien-object (type-spec location &optional alloc)
  -  ;; Reference counted objects are always treated as if alloc were :reference
  -  (declare (ignore alloc)) 
     `(let ((location ,location))
        (unless (null-pointer-p location)
  -       (ensure-alien-instance ',type-spec location))))
  -
  -(deftype-method
  -    cleanup-alien alien-object (type-spec sap &optional copied)
  -  (when copied
  -    `(let ((sap ,sap))
  -       (unless (null-pointer-p sap)
  -	 (,(alien-unref type-spec) sap)))))
  -
  -
  -
  -;;;; Superclass for wrapping of non-refcounted structures
  +       (ensure-proxy-instance
  +	(%type-of-ginstance location) location ,weak-ref))))
  +
  +(deftype-method translate-to-alien
  +    ginstance (type-spec object &optional weak-ref)
  +  (declare (ignore type-spec))
  +  (if weak-ref
  +      `(proxy-location ,object)
  +    `(let ((object ,object))
  +       (funcall
  +	(ginstance-class-ref (class-of object)) (proxy-location object)))))
  +
  +(deftype-method unreference-alien ginstance (type-spec location)
  +  (declare (ignore type-spec))
  +  `(let* ((location ,location)
  +	  (class (find-class (%type-of-ginstance location))))
  +     (funcall (ginstance-class-unref class) location)))
  +
  +
  +
  +;;;; Metaclass for subclasses of ginstance
   
   (eval-when (:compile-toplevel :load-toplevel :execute)
  -  (defclass alien-structure (alien-instance)
  -    ((static
  -      :allocation :instance
  -      :reader alien-structure-static-p
  -      :initform nil
  -      :type boolean))
  -    (:metaclass alien-class)
  -    (:size 0)))
  -
  -(define-type-method-fun alien-copier (type-spec))
  -(define-type-method-fun alien-deallocator (type-spec))
  -
  -(defmethod from-alien-initialize-instance ((structure alien-structure)
  -					   &rest initargs &key static)
  -  (declare (ignore initargs))
  -  (call-next-method)
  -  (setf (slot-value structure 'static) static))
  -
  -(defmethod instance-finalizer ((structure alien-structure))
  -  (let ((location (alien-instance-location structure)))
  -    (declare (type system-area-pointer location))
  -    (if (alien-structure-static-p structure)
  -	#'(lambda ()
  -	    (remove-cached-instance location))
  -      (let ((deallocator
  -	     (fdefinition (alien-deallocator (class-of structure)))))
  -	(declare (type function deallocator))
  -	#'(lambda ()
  -	    (remove-cached-instance location)
  -	    (funcall deallocator location))))))
  -
  -
  -(deftype-method alien-copier alien-structure (type-spec)
  -  (declare (ignore type-spec))
  -  'copy-memory)
  -
  -(deftype-method alien-deallocator alien-structure (type-spec)
  -  (declare (ignore type-spec))
  -  'deallocate-memory)
  -
  -(deftype-method translate-to-alien
  -    alien-structure (type-spec object &optional copy)
  -  `(let ((object ,object))
  -     (if (and ,copy (not (alien-structure-static-p object)))
  -	 (,(alien-copier type-spec)
  -	  `(alien-instance-location object)
  -	  ,(alien-class-size (find-class type-spec)))
  -       (alien-instance-location object))))
  -
  -(deftype-method translate-from-alien
  -    alien-structure (type-spec location &optional (alloc :reference))
  -  `(let ((location ,location))
  -     (unless (null-pointer-p location)
  -       ,(ecase alloc
  -	  (:copy `(ensure-alien-instance ',type-spec location))
  -	  (:static `(ensure-alien-instance ',type-spec location :static t))
  -	  (:reference
  -	   `(ensure-alien-instance
  -	     ',type-spec
  -	     (,(alien-copier type-spec)
  -	      location ,(alien-class-size (find-class type-spec)))))))))
  -
  -(deftype-method cleanup-alien alien-structure (type-spec sap &optional copied)
  -  (when copied
  -    `(let ((sap ,sap))
  -       (unless (or
  -		(null-pointer-p sap)
  -		(alien-structure-static-p (find-cached-instance sap)))
  -	 (,(alien-deallocator type-spec) sap)))))
  -
  -
  -
  -;;;; Superclass for static structures such as gdk:visual
  -
  -(defclass static-structure (alien-structure)
  -  ()
  -  (:metaclass alien-class)
  -  (:size 0))
  -
  -
  -(defmethod from-alien-initialize-instance ((structure alien-structure)
  -				      &rest initargs)
  -  (declare (ignore initargs))
  -  (call-next-method)
  -  (setf (slot-value structure 'static) t))
  -
  -
  -
  -;;;; Superclass wrapping types in the glib type system
  -
  -(eval-when (:compile-toplevel :load-toplevel :execute)
  -  (defclass ginstance (alien-object)
  -    ()
  -    (:metaclass alien-class)
  -    (:size 4 #|(size-of 'pointer)|#)))
  -
  -
  -(defun %alien-instance-type-number (location)
  -  (let ((class (sap-ref-sap location 0)))
  -    (sap-ref-unsigned class 0)))
  -
  -
  -(deftype-method translate-from-alien ginstance (type-spec location &optional alloc)
  -  (declare (ignore type-spec alloc))
  -  `(let ((location ,location))
  -     (unless (null-pointer-p location)
  -       (ensure-alien-instance
  -	(type-from-number (%alien-instance-type-number location))
  -	location))))
  -
  -
  -
  -;;;; Metaclass for subclasses of ginstance-class
  -
  -(eval-when (:compile-toplevel :load-toplevel :execute)
  -  (defclass ginstance-class (alien-class)))
  +  (defclass ginstance-class (proxy-class)
  +    ((ref :reader ginstance-class-ref)
  +     (unref :reader ginstance-class-unref))))
   
   
   (defmethod shared-initialize ((class ginstance-class) names
  -			      &rest initargs &key name)
  +			      &rest initargs
  +			      &key name alien-name size
  +			      ref unref type-init)
     (declare (ignore initargs names))
     (call-next-method)
  -  (setf
  -   (slot-value class 'size)
  -   (type-instance-size (find-type-number (or name (class-name class))))))
  +
  +  (let* ((class-name (or name (class-name class)))
  +	 (type-number
  +	  (cond
  +	   ((and alien-name type-init)
  +	    (error
  +	     "Specify either :type-init or :alien-name for class ~A"
  +	     class-name))
  +	   (alien-name (type-number-from-alien-name (first alien-name)))
  +	   (type-init (type-init class-name (first type-init)))
  +	   (t
  +	    (or
  +	     (type-number-from-alien-name
  +	      (default-alien-type-name class-name) nil)
  +	     (type-init class-name))))))
  +    (setf (find-type-number class) type-number)
  +    (unless size
  +      (setf
  +       (slot-value class 'size)
  +       (type-instance-size (find-type-number class-name))))
  +    (when ref
  +      (setf
  +       (slot-value class 'ref)
  +       (alien-function (first ref) 'system-area-pointer 'system-area-pointer)))
  +    (when unref
  +      (setf
  +       (slot-value class 'unref)
  +       (alien-function (first unref) 'void 'system-area-pointer)))))
  +
  +(defmethod shared-initialize :after ((class ginstance-class) names
  +				     &rest initargs)
  +  (declare (ignore names initargs))
  +  (unless (slot-boundp class 'ref)
  +    (setf
  +     (slot-value class 'ref)
  +     (ginstance-class-ref (most-specific-proxy-superclass class))))
  +  (unless (slot-boundp class 'unref)
  +    (setf
  +     (slot-value class 'unref)
  +     (ginstance-class-unref (most-specific-proxy-superclass class)))))
   
   
   (defmethod validate-superclass
       ((class ginstance-class) (super pcl::standard-class))
     (subtypep (class-name super) 'ginstance))
  -
  -
  -; (defmethod allocate-alien-storage ((class ginstance-class))
  -;   (type-create-instance (find-type-number class)))
   
   
   ;;;; Initializing type numbers
  
positive.code: (setf (alien-type-name 'unsigned-int) "guint")
  (setf (alien-type-name 'long) "glong")
  (setf (alien-type-name 'unsigned-long) "gulong")
  (setf (alien-type-name 'enum) "GEnum")
  (setf (alien-type-name 'flags) "GFlags")
  (setf (alien-type-name 'single-float) "gfloat")
  (setf (alien-type-name 'double-float) "gdouble")
  (setf (alien-type-name 'string) "gstring")
  (setf (find-type-number 'fixnum) (find-type-number 'int))
  
negative.code: 
  (deftype type-number () '(unsigned 32))
  
  (eval-when (:compile-toplevel :load-toplevel :execute)
    (defclass type-query (alien-structure)
      ((type-number :allocation :alien :type type-number)
       (name :allocation :alien :type string)
       (class-size :allocation :alien :type unsigned-int)
       (instance-size :allocation :alien :type unsigned-int))
      (:metaclass proxy-class)))
  
  
  (defbinding ("g_type_name" alien-type-name) (type) (static string)
    ((find-type-number type) type-number))
  
  (defbinding %type-from-name () type-number
    (name string))
  
  (defbinding type-parent () type-number
    (type type-number))
  
  (defbinding %type-query () nil
    (type type-number)
    (query type-query))
  
  (defun type-query (type)
    (let ((query (make-instance 'type-query)))
      (%type-query (find-type-number type) query)
      query))
  
  (defun type-instance-size (type)
    (slot-value (type-query type) 'instance-size))
  
  (defun type-class-size (type)
    (slot-value (type-query type) 'class-size))
  
  (defbinding type-class-ref () pointer
    (type type-number))
  
  (defbinding type-class-unref () nil
    (type type-number))
  
  (defbinding type-class-peek () pointer
    (type type-number))
  
  (defbinding type-create-instance (type) pointer
    ((find-type-number type) type-number))
  
  (defbinding type-free-instance () nil
    (instance pointer))
  
  
  