This package provides a prefix \named to be used in TeX
definitions so that parameters can be identified by their name
rather than by number, giving parameters a semantic rather than
syntactic meaning, making it easy to understand long
definitions. A usual definition reads: \def\SayHello#1{Hello,
\named\def\SayHello#[person]{Hello, #[person]!} and \named will
figure out the numbering of the parameters for you.