• Each line must be terminated by a %, without a space before it. Empty lines are allowed, but not lines with nothing but spaces in them.
• \begin{macro} and \end{macro} must be paired.
• \begin{macrocode} and \end{macrocode} must be paired.
• \begin{macro} must have a second argument.
• One space must be printed between % and \begin{macro} or \end{macro}. % must be the first character in the line.
• Four spaces must be printed between % and \begin{macrocode} or \end{macrocode}.
• \cs argument must not start with a backslash.

The author is Maïeul Rouquette. The package is Copyright © 2014-2016 Maïeul Rouquette.