X-Git-Url: https://git.hcoop.net/clinton/lisp-on-lines.git/blobdiff_plain/6de8d30004efc9337b8c40d2ff2d0a76651d23eb..f56d6e7e926f9c3f968325e244794ff748435ac3:/src/display.lisp

diff --git a/src/display.lisp b/src/display.lisp
index 28957a9..6078e83 100644
--- a/src/display.lisp
+++ b/src/display.lisp
@@ -1,45 +1,53 @@
 (in-package :lisp-on-lines)
 
-(defvar *description*)
-(defvar *display*)
-(defvar *object* nil)
 
+(defvar *display*)
 
-(deflayer display-layer)
 
 (define-layered-function display-using-description (description display object &rest args)
   (:documentation
    "Displays OBJECT via description using/in/with/on display"))
 
-(defun display (display object &rest args &key attributes )
-  (let ((*display-attributes* attributes))
-    (apply #'display-using-description (description-of object) display object args)))
+
+
+(defun modify-layer-context (context &key activate deactivate)
+  (dolist (d deactivate)
+    (setf context (remove-layer (find-description d)
+				context)))
+  (dolist (d activate context)
+    (setf context (adjoin-layer (find-description d)
+				context))))
+
+(defun funcall-with-attribute-context (attribute thunk)
+  (funcall-with-layer-context 
+   (modify-layer-context (current-layer-context) 
+			 :activate (attribute-active-descriptions attribute)
+			 :deactivate (attribute-inactive-descriptions attribute))
+   thunk))
+
+(defmacro with-attribute-context ((attribute) &body body)
+  `(funcall-with-attribute-context ,attribute (lambda () ,@body)))
+  
+  
+(defun display (display object &rest args &key deactivate activate &allow-other-keys)
+
+  (funcall-with-layer-context 
+   (modify-layer-context (current-layer-context) 
+			 :activate activate 
+			 :deactivate deactivate)
+   (lambda () 
+     (apply #'display-using-description (description-of object) display object args))))
 
 (define-layered-method display-using-description 
   :around (description display object &rest args)
   (declare (ignorable args))
-  (let ((*description* description)
-	(*display* display)
-	(*object*  object))
-    (contextl::funcall-with-special-initargs  
-      (loop 
-	 :for (key val) :on args :by #'cddr
-	 :collect (list (find key (description-attributes description) 
-			      :key #'attribute-keyword)
-			:value val))
-      (lambda ()
-	(contextl::funcall-with-special-initargs  
-	 (let ((attribute (find-attribute description 'active-attributes)))	
-	   (when attribute
-	     (loop for spec in (attribute-value object attribute)
-		  if (listp spec)
-		  collect (cons (or 
-				 (find-attribute description (car spec))
-						 (error "No attribute matching ~A" (car spec)))
-				 (cdr spec)))))
+#+nil  (break "Entering DISPLAY for ~A on ~A using ~A" object display description)
+  (let ((*display* display))
+    (apply #'funcall-with-described-object 
      (lambda ()
-       (call-next-method)))))))
-			      
+       (call-next-method))
+     object description args)))
+
 
 
 (defun display/d (&rest args)
@@ -62,7 +70,7 @@ OMGWTF! If you didn't do this, it's a bug!" description display object args))
 	(return
 	  (destructuring-bind (description-spec &optional  (display-spec (gensym)) (object-spec (gensym))) 
 	      (car tail) 
-		`(define-layered-method
+	    `(define-layered-method
 		  display-using-description
 		   :in-layer ,(if (eq t description) 
 				  t