1 (in-package :lisp-on-lines
)
7 (define-layered-function display-using-description
(description display object
&rest args
)
9 "Displays OBJECT via description using/in/with/on display"))
13 (defun modify-layer-context (context &key activate deactivate
)
14 (dolist (d deactivate
)
15 (setf context
(remove-layer (find-description d
)
17 (dolist (d activate context
)
18 (setf context
(adjoin-layer (find-description d
)
24 (defun display (display object
&rest args
&key deactivate activate
&allow-other-keys
)
26 (funcall-with-layer-context
27 (modify-layer-context (current-layer-context)
29 :deactivate deactivate
)
31 (apply #'display-using-description
(description-of object
) display object args
))))
33 (define-layered-method display-using-description
34 :around
(description display object
&rest args
)
35 (declare (ignorable args
))
36 #+nil
(break "Entering DISPLAY for ~A on ~A using ~A" object display description
)
37 (let ((*display
* display
))
38 (apply #'funcall-with-described-object
41 object description args
)))
47 (defun display/d
(&rest args
)
48 (apply #'display-using-description args
))
50 (define-layered-method display-using-description
(description display object
&rest args
)
51 (error "No DISPLAY-USING-DESCRIPTION methods are specified for: ~% DESCRIPTION: ~A ~% DISPLAY: ~A ~% OBJECT: ~A ~% ARGS: ~S
53 OMGWTF! If you didn't do this, it's a bug!" description display object args
))
55 (defmacro define-display
(&body body
)
56 (loop with in-descriptionp
= (eq (car body
) :in-description
)
57 with description
= (if in-descriptionp
(cadr body
) 't
)
58 for tail on
(if in-descriptionp
(cddr body
) body
)
59 until
(listp (car tail
))
60 collect
(car tail
) into qualifiers
62 (when (member :in-description qualifiers
)
63 (error "Incorrect occurrence of :in-description in defdisplay. Must occur before qualifiers."))
65 (destructuring-bind (description-spec &optional
(display-spec (gensym)) (object-spec (gensym)))
67 `(define-layered-method
68 display-using-description
69 :in-layer
,(if (eq t description
)
71 (defining-description description
))
73 (,(if (listp description-spec
)
74 (list (first description-spec
)
75 (if (eq 'description
(second description-spec
))
77 (defining-description (second description-spec
)))))
79 ,object-spec
&rest args
)
80 (declare (ignorable args
))