Assertion: exception's argument | /r/HasProperty | an instance of exn
Facets:
Source sentences:
text: The default uncaught-exception handler prints an error message using the current error display handler (see error-display-handler), unless the argument to the handler is an instance of exn:break:hang-up.
text: If the argument to the handler is an instance of exn:break:hang-up or exn:break:terminate, the default uncaught-exception handler then calls the exit handler with 1, which normally exits or escapes.