From c29b2d2dda5ab82f7458666c154094693bfe9f1b Mon Sep 17 00:00:00 2001
From: drewc <drewc@tech.coop>
Date: Thu, 28 Aug 2008 13:16:32 -0700
Subject: [PATCH] Added NULL description and added :when option for attribute
 active

darcs-hash:20080828201632-39164-a2a9ccf0c2e99f36046543911b7158bb276c9e73.gz
---
 lisp-on-lines.asd  | 10 ++++++----
 src/attribute.lisp |  6 ++++++
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/lisp-on-lines.asd b/lisp-on-lines.asd
index 0e32bf7..f4af77b 100644
--- a/lisp-on-lines.asd
+++ b/lisp-on-lines.asd
@@ -60,7 +60,9 @@ OTHER DEALINGS IN THE SOFTWARE."
 							   (:file "edit")
 							   (:file "symbol")
 							   (:file "list")
-							   (:file "clos"))
+							   (:file "null")
+							   (:file "clos")
+							   )
 							   
 					      :serial t))
 				     
@@ -68,9 +70,9 @@ OTHER DEALINGS IN THE SOFTWARE."
   :serial t
   :depends-on (:contextl :arnesi :alexandria :parse-number
 			 ;;for rofl:
-			  :cl-postgres :simple-date :postmodern))
-
-
+			 :cl-postgres
+			 :simple-date-postgres
+			 :postmodern ))
 
 
 (defsystem :lisp-on-lines.test
diff --git a/src/attribute.lisp b/src/attribute.lisp
index 210b36d..d332f60 100644
--- a/src/attribute.lisp
+++ b/src/attribute.lisp
@@ -134,6 +134,12 @@
 		       :layered t
 		       :special t)))
 
+(define-layered-method attribute-active-p :around (attribute)		       
+ (let ((active? (call-next-method)))
+   (if (eq :when active?)
+       (not (null (attribute-value attribute)))
+       active?)))
+		       
 (define-layered-method attribute-label-formatter :around (attribute)
    (or (slot-value attribute 'label-formatter) 
        (attribute-value (find-attribute (attribute-description attribute) 'label-formatter))
-- 
2.20.1