versionPO.sty

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% You need Rainer Schoepf's verbatim.sty to use this!!
%
% Version control macros. These let you define environments whose contents
% will be optionally added to or deleted from the text when you run LaTeX.
% Usage: place either of the following near the start of your file:
%     \includeversion{NAME}
%     \excludeversion{NAME}
% Here, "NAME" is any name you choose. The first one indicates that text
% between \begin{NAME} and \end{NAME} will be processed in the normal way.
% The second indicates that text between \begin{NAME} and \end{NAME} will
% be totally deleted.
% These command automatically declare the inverted version not-NAME.
%
% NOTE:
% You cannot use the version environments inside another environment,
% inside a command or in an argument to another command. You can make a
% limited use of a version inside an environment by using \NAME and
% \endNAME rather than \begin{NAME} and \end{NAME}. E.g.
%   \newenvironment{example}{...\myversion...}{\endmyversion} where the
% following would fail:
%   \newenvironment{example}{...\begin{myversion}...}{\end{myversion}}
%
% To alleviate these problems a bit, foreach version NAME also a command
% \ifNAME is defined such that \ifNAME{yes-part}{no-part} selects either
% yes-part or no-part depending on whether the version is included or
% excluded. The \ifNAME command may be used everywhere but the environments
% are preferred with large amounts of text. Also the parameters of \ifNAME
% are not included in a group, so you can make global declarations in them.
% The \ifNAME command is fragile if either of its arguments is fragile.
% Note: the \ifNAME command is only usable if NAME consists of letters only.
%
% A ``comment'' environment has already been pre-defined for you with 
% \excludeversion{comment}; you can NOT override this one.
%
% You can define environments for as many versions as you want. 
%
% Example: 
%   \includeversion{abridged}
%   \ifabridged{\large}{\small}
%   Text for the
%   \begin{abridged} 
%      short
%   \end{abridged}
%   \begin{not-abridged}
%      long and really longwinded, opaque and boring
%   \end{not-abridged}
%   version of the paper. Punctuation works correctly\begin{not-abridged}
%   because sphack is used\end{not-abridged}.
%   \begin{comment} This is deleted by default. \end{comment}
%
%  Piet van Oostrum -- <piet@cs.ruu.nl>
%  Idea based on a style file by Stephen Bellantoni, implementation based
%  on verbatim.sty by Rainer Schoepf <SCHOEPF@SC.ZIB-Berlin.DE>.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\@ifundefined{verbatim@@@}{\input{verbatim.sty}}{}

\def\includeversion#1{%
  \expandafter\def\csname #1\endcsname{}%
  \expandafter\def\csname end#1\endcsname{}%
  \expandafter\let\csname not-#1\endcsname\comment
  \expandafter\let\csname endnot-#1\endcsname\endcomment
  \expandafter\def\csname if#1\endcsname##1##2{##1}
}
\def\excludeversion#1{%
  \expandafter\let\csname #1\endcsname\comment
  \expandafter\let\csname end#1\endcsname\endcomment
  \expandafter\def\csname not-#1\endcsname{}%
  \expandafter\def\csname endnot-#1\endcsname{}%
  \expandafter\def\csname if#1\endcsname##1##2{##2}
}