-(put 'nxml-outline-error
- 'error-conditions
- '(error nxml-error nxml-outline-error))
-
-(put 'nxml-outline-error
- 'error-message
- "Cannot create outline of buffer that is not well-formed")
+(define-error 'nxml-outline-error
+ "Cannot create outline of buffer that is not well-formed" 'nxml-error)