(PARAMETER (t "param")) ; Argument of preceding annotation
;; The following are not part of the standard:
(FUNCTION (enriched-decode-foreground "x-color")
- (enriched-decode-background "x-bg-color"))
+ (enriched-decode-background "x-bg-color")
+ (enriched-decode-display-prop "x-display"))
(read-only (t "x-read-only"))
+ (display (nil enriched-handle-display-prop))
(unknown (nil format-annotate-value))
; (font-size (2 "bigger") ; unimplemented
; (-2 "smaller"))
(message "Warning: color `%s' can't be displayed" color)))
(list from to 'face face)))
+
+\f
+;;; Handling the `display' property.
+
+
+(defun enriched-handle-display-prop (old new)
+ "Return a list of annotations for a change in the `display' property.
+OLD is the old value of the property, NEW is the new value. Value
+is a list `(CLOSE OPEN)', where CLOSE is a list of annotations to
+close and OPEN a list of annotations to open. Each of these lists
+has the form `(ANNOTATION PARAM ...)'."
+ (let ((annotation "x-display")
+ (param (prin1-to-string (or old new)))
+ close open)
+ (if (null old)
+ (list nil (list annotation param))
+ (list (list annotation param)))))
+
+
+(defun enriched-decode-display-prop (start end &optional param)
+ "Decode a `display' property for text between START and END.
+PARAM is a `<param>' found for the property.
+Value is a list `(START END SYMBOL VALUE)' with START and END denoting
+the range of text to assign text property SYMBOL with value VALUE "
+ (let ((prop (when (stringp param)
+ (condition-case ()
+ (car (read-from-string param))
+ (error nil)))))
+ (unless prop
+ (message "Warning: invalid <x-display> parameter %s" param))
+ (list start end 'display prop)))
+
+
;;; enriched.el ends here