%\ifx\undefined\eplain \input eplain \fi

\hsize = 32pc
\emergencystretch = 8pc
%\tolerance = 10000

\def\code#1{{\tt #1}}
\def\\{{\tt \char92}}

You can make a new numbered theorem-like environment with
\code{\\definenumberedtheorem}.  This macro takes one argument, the name
of the environment.  The first letter of the name will be capitalized
when it is typeset.  Analogously, you can use
\code{\\defineunnumberedtheorem} to make a new unnumbered theorem-like
environment.  These commands can only be used before \code{\\body}.

\end
