\end{describe}
\begin{describe}{mac}
- {test-parser (@<scanner>) @<parser> @<input>
- @> @<success-flag> @<result> @<remainder>}
+ {test-parser (@<scanner> \&key :backtrace) @<parser> @<input>
+ @> @<result> @<status> @<remainder>}
\end{describe}
\begin{describe}{fun}{exercise}