args
next)))
primary-emf)))
-\f
-;;;; example
-(defclass cons-specializer (extended-specializer)
- ((car :initarg :car :reader %car)))
-(defclass cons-generic-function (specializable-generic-function)
- ()
- (:metaclass sb-mop:funcallable-standard-class))
-
-(define-extended-specializer cons (gf car)
- (make-instance 'cons-specializer :car car))
-
-(defmethod sb-pcl:unparse-specializer-using-class
- ((gf cons-generic-function) (specializer cons-specializer))
- `(cons ,(%car specializer)))
-(defmethod sb-pcl::same-specializer-p
- ((s1 cons-specializer) (s2 cons-specializer))
- (eql (%car s1) (%car s2)))
-
-(defmethod generalizer-of-using-class ((gf cons-generic-function) arg)
- (typecase arg
- ((cons symbol) (car arg))
- (t (call-next-method))))
-;;; FIXME: it looks like these protocol functions should have the GF
-;;; as an argument, since generalizer-of-using-class does
-(defmethod specializer-accepts-generalizer-p ((specializer cons-specializer) thing)
- (if (eql (%car specializer) thing)
- (values t t)
- (values nil t)))
-;;; FIXME: yes, definitely need the gf!
-(defmethod specializer-accepts-generalizer-p (specializer (thing symbol))
- (specializer-accepts-generalizer-p specializer (find-class 'cons)))
-
-(defmethod specializer-accepts-p ((specializer cons-specializer) obj)
- (and (consp obj)
- (eql (car obj) (%car specializer))))
-(defmethod specializer< ((s1 cons-specializer) (s2 cons-specializer) generalizer)
- (declare (ignore generalizer))
- (if (eql (%car s1) (%car s2))
- '=
- nil))
-(defmethod specializer< ((s1 cons-specializer) (s2 class) generalizer)
- (declare (ignore generalizer))
- '<)
-(defmethod specializer< ((s1 cons-specializer) (s2 sb-mop:eql-specializer) generalizer)
- (declare (ignore generalizer))
- '>)
-(defmethod specializer< ((s1 sb-mop:specializer) (s2 cons-specializer) generalizer)
- (ecase (specializer< s2 s1 generalizer)
- ((<) '>)
- ((>) '<)))
-
-(defgeneric walk (form)
- (:generic-function-class cons-generic-function))
-
-(defmethod walk ((form symbol))
- `(lookup ,form))
-(defmethod walk ((form cons))
- `(call (flookup ,(car form)) (list ,@(mapcar #'walk (cdr form)))))
-(defmethod walk ((form (cons quote)))
- (cadr form))
-(defmethod walk ((form (cons let)))
- (let ((bindings (cadr form)))
- `(with-bindings ,bindings ,@(cddr form))))