e7c5f95a |
1 | (in-package :lisp-on-lines) |
2 | |
4358148e |
3 | (defvar *description*) |
e7c5f95a |
4 | (defvar *display*) |
4358148e |
5 | (defvar *object*) |
6 | |
7 | (deflayer display-layer) |
e7c5f95a |
8 | |
9 | (define-layered-function display-using-description (description display object &rest args) |
10 | (:documentation |
11 | "Displays OBJECT via description using/in/with/on display")) |
12 | |
4271ab0b |
13 | (defun display (display object &rest args &key attributes ) |
14 | (let ((*display-attributes* attributes)) |
15 | (display-using-description (description-of object) display object args))) |
e7c5f95a |
16 | |
17 | (define-layered-method display-using-description |
18 | :around (description display object &rest args) |
4358148e |
19 | (declare (ignorable args)) |
20 | (let ((*description* description) |
21 | (*display* display) |
e7c5f95a |
22 | (*object* object)) |
23 | (call-next-method))) |
24 | |
4271ab0b |
25 | (defun display/d (&rest args) |
26 | (apply #'display-using-description args)) |
27 | |
4358148e |
28 | |
29 | |
e7c5f95a |
30 | (define-layered-method display-using-description (description display object &rest args) |
31 | (error "No DISPLAY-USING-DESCRIPTION methods are specified for: ~% DESCRIPTION: ~A ~% DISPLAY: ~A ~% OBJECT: ~A ~% ARGS: ~S |
32 | |
33 | OMGWTF! If you didn't do this, it's a bug!" description display object args)) |
34 | |
4358148e |
35 | |
e7c5f95a |
36 | |
37 | (defmacro define-display (&body body) |
4358148e |
38 | (loop with in-descriptionp = (eq (car body) :in-description) |
39 | with description = (if in-descriptionp (cadr body) 't) |
40 | for tail on (if in-descriptionp (cddr body) body) |
e7c5f95a |
41 | until (listp (car tail)) |
42 | collect (car tail) into qualifiers |
43 | finally |
4358148e |
44 | (when (member :in-description qualifiers) |
45 | (error "Incorrect occurrence of :in-description in defdisplay. Must occur before qualifiers.")) |
e7c5f95a |
46 | (return |
47 | (destructuring-bind (description-spec &optional (display-spec (gensym)) (object-spec (gensym))) |
48 | (car tail) |
49 | `(define-layered-method |
50 | display-using-description |
4358148e |
51 | :in-layer ,(if (eq t description) |
52 | t |
53 | (defining-description description)) |
e7c5f95a |
54 | ,@qualifiers |
55 | (,(if (listp description-spec) |
56 | (list (first description-spec) |
57 | (if (eq 'description (second description-spec)) |
58 | 'description |
59 | (defining-description (second description-spec))))) |
60 | ,display-spec |
61 | ,object-spec &rest args) |
62 | (declare (ignorable args)) |
63 | ,@(cdr tail)))))) |
64 | |
65 | |
66 | |
67 | |