+(defun %type-of-ginstance (location)
+ (let ((class (sap-ref-sap location 0)))
+ (type-from-number (sap-ref-32 class 0))))
+
+(defmethod ensure-proxy-instance ((class ginstance-class) location)
+ (declare (ignore class))
+ (let ((class (find-class (%type-of-ginstance location))))
+ (if class
+ (make-instance class :location (reference-foreign class location))
+ ;; TODO: (make-instance 'ginstance ...)
+ location)))
+
+(defmethod copy-from-alien-form (location (class ginstance-class) &rest args)
+ (declare (ignore location class args))
+ (error "Doing copy-from-alien on a ref. counted class is most certainly an error, but if it really is what you want you should use REFERENCE-FOREIGN on the returned instance instead."))
+
+(defmethod copy-from-alien-function ((class ginstance-class) &rest args)
+ (declare (ignore class args))
+ (error "Doing copy-from-alien on a ref. counted class is most certainly an error, but if it really is what you want you should use REFERENCE-FOREIGN on the returned instance instead."))
+
+(defmethod reader-function ((class ginstance-class) &rest args)
+ (declare (ignore args))
+ #'(lambda (location &optional (offset 0))
+ (ensure-proxy-instance class (sap-ref-sap location offset))))
+
+
+;;;; Registering fundamental types
+
+(register-type 'nil "void")
+(register-type 'pointer "gpointer")
+(register-type 'char "gchar")
+(register-type 'unsigned-char "guchar")
+(register-type 'boolean "gboolean")
+(register-type 'int "gint")
+(register-type-alias 'fixnum 'int)
+(register-type 'unsigned-int "guint")
+(register-type 'long "glong")
+(register-type 'unsigned-long "gulong")
+(register-type 'single-float "gfloat")
+(register-type 'double-float "gdouble")
+(register-type 'pathname "gchararray")
+(register-type 'string "gchararray")
+
+
+;;;; Introspection of type information
+
+(defvar *derivable-type-info* (make-hash-table))
+
+(defun register-derivable-type (type id expander &optional dependencies)
+ (register-type type id)
+ (let ((type-number (register-type type id)))
+ (setf
+ (gethash type-number *derivable-type-info*)
+ (list expander dependencies))))
+
+(defun find-type-info (type)
+ (dolist (super (cdr (type-hierarchy type)))
+ (let ((info (gethash super *derivable-type-info*)))
+ (return-if info))))
+
+(defun expand-type-definition (type forward-p options)
+ (let ((expander (first (find-type-info type))))
+ (funcall expander (find-type-number type t) forward-p options)))
+
+(defbinding type-parent (type) type-number
+ ((find-type-number type t) type-number))
+
+(defun supertype (type)
+ (type-from-number (type-parent type)))
+
+(defbinding %type-interfaces (type) pointer
+ ((find-type-number type t) type-number)
+ (n-interfaces unsigned-int :out))
+
+(defun type-interfaces (type)
+ (multiple-value-bind (array length) (%type-interfaces type)
+ (unwind-protect
+ (map-c-vector 'list #'identity array 'type-number length)
+ (deallocate-memory array))))
+
+(defun implements (type)
+ (mapcar #'type-from-number (type-interfaces type)))
+
+(defun type-hierarchy (type)
+ (let ((type-number (find-type-number type t)))
+ (unless (= type-number 0)
+ (cons type-number (type-hierarchy (type-parent type-number))))))
+
+(defbinding (type-is-p "g_type_is_a") (type super) boolean
+ ((find-type-number type) type-number)
+ ((find-type-number super) type-number))
+
+(defbinding %type-children () pointer
+ (type-number type-number)
+ (num-children unsigned-int :out))
+
+(defun map-subtypes (function type &optional prefix)
+ (let ((type-number (find-type-number type t)))
+ (multiple-value-bind (array length) (%type-children type-number)
+ (unwind-protect
+ (map-c-vector
+ 'nil
+ #'(lambda (type-number)
+ (when (or
+ (not prefix)
+ (string-prefix-p prefix (find-foreign-type-name type-number)))
+ (funcall function type-number))
+ (map-subtypes function type-number prefix))
+ array 'type-number length)
+ (deallocate-memory array)))))
+
+(defun find-types (prefix)
+ (let ((type-list nil))
+ (maphash
+ #'(lambda (type-number expander)
+ (declare (ignore expander))
+ (map-subtypes
+ #'(lambda (type-number)
+ (pushnew type-number type-list))
+ type-number prefix))
+ *derivable-type-info*)
+ type-list))
+
+(defun find-type-dependencies (type)
+ (let ((list-dependencies (second (find-type-info type))))
+ (when list-dependencies
+ (funcall list-dependencies (find-type-number type t)))))
+
+(defun %sort-types-topologicaly (types)
+ (let ((partial-sorted
+ (sort
+ (mapcar
+ #'(lambda (type)
+ (cons type (remove-if #'(lambda (dep)
+ (not (find dep types)))
+ (find-type-dependencies type))))
+ types)
+ #'(lambda (type1 type2) (type-is-p type2 type1)) :key #'car))
+ (sorted ()))
+
+ (loop
+ as tmp = partial-sorted then (or (rest tmp) partial-sorted)
+ while tmp
+ do (destructuring-bind (type . dependencies) (first tmp)