+ (concatenate-strings (rest strings) delimiter))))
+
+(defun string-prefix-p (prefix string)
+ (and
+ (>= (length string) (length prefix))
+ (string= prefix string :end2 (length prefix))))
+
+(defun get-all (plist property)
+ (multiple-value-bind (property value tail)
+ (get-properties plist (list property))
+ (when tail
+ (cons value (get-all (cddr tail) property)))))
+
+(defun plist-remove (plist property)
+ (when plist
+ (if (eq (first plist) property)
+ (plist-remove (cddr plist) property)
+ (list*
+ (first plist) (second plist) (plist-remove (cddr plist) property)))))