Format of Exception Port Messages

The Exception port shows the exception term describing the exception that has been raised. This is printed on a separate line before the line printed for the port itself. For example:

     ! type_error(_2069 is a,2,'arithmetic expression',a)
        (2) 1 Exception (built_in): _2050 is a ?
     

For exception term formats or more information about the exception handling system of Quintus Prolog, see ref-ere.