#'attribute-active-p
(description-attributes description)))
-(defun find-attribute (description attribute-name)
- (find attribute-name (description-attributes description)
- :key #'attribute-name))
+(defun find-attribute (description attribute-name &optional (errorp t))
+ (or (find attribute-name (description-attributes description)
+ :key #'attribute-name)
+ (when errorp (error "No attribute named ~A found in ~A" attribute-name description))))
(define-layered-function description-active-descriptions (description)
(:method ((description standard-description-object))