At 21:09 +0200 98/10/21, Martin Schroeder wrote: > >\newenvironment{foo}{start}{end} defines \foo{start} and \endfoo{end}. > >But this is an undocumented feature -- which you can use at your own >risk. Hans Aberg <mailto:[log in to unmask]> > So LaTeX defines \begin{list} and \end{list} as a part of the >list-environment interface, but \list and \endlist are part of the >implementation of the list environment. ... > ... \list and \endlist do not belong to the interface, All untrue! The command equivalent of an environment is "documented" on pages 25 and 34 of Lamport's Manual (1st ed; check the index for Environment > made from declaration). It's not *well* documented, (omitting mention of the \end form) but it is clearly intended to be part of the user interface. For the package or class writer, it is *preferred* to use the commands rather than the environments for two reasons: - less overhead and stack use (minor) - better syntax checking (important!) Let's say you use \begin{list} when defining a new environment {citation}, and a document has omitted \end{citation}. The error message you get is ! LaTeX Error: \begin{list} on input line xx ended by \end{document}. but if you use \list and \endlist you get the proper ! LaTeX Error: \begin{citation} on input line xx ended by \end{document}. Donald Arseneau [log in to unmask]