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% \iffalse
%% Package `export' to use with LaTeX 2e
%% Copyright (C) 1996, 1997, 1998, 1999 Jean-Pierre F. Drucbert, all rights reserved
%%
%% You may use and distribute this file freely, provided that
%% you don't pretend that you wrote it.
%
% It may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.1
% of this license or (at your option) any later version.
% The latest version of this license is in
%    http://www.latex-project.org/lppl.txt
% and version 1.1 or later is part of all distributions of LaTeX 
% version 1999/06/01 or later.
%
%<package>\NeedsTeXFormat{LaTeX2e}[1996/06/01]
%<package>\ProvidesPackage{export}
%<package>         [2000/10/16 v1.8 Exportation of LaTeX registers (JPFD)]
%
%<*driver>
\documentclass{ltxdoc}
\GetFileInfo{export.sty}
\def\filedate{2000/10/16}
\def\fileversion{v1.8}
\usepackage{array,multicol}
\EnableCrossrefs         
%\DisableCrossrefs   % Say \DisableCrossrefs if index is ready
\RecordChanges                  % Gather update information
\CodelineIndex                  % Index code by line number
\title{The \pkg{export} package}
\author{Jean-Pierre F. Drucbert\\\texttt{drucbert@onecert.fr}}%
\date{\filedate}
\def\bs{\texttt{\char'134}}
\newlength{\clw}\setlength{\clw}{0.39\textwidth}
\let\pkg\textsf
\begin{document}
\maketitle
\DocInput{export.dtx}
\end{document}
%</driver>
% \fi
%
% \CheckSum{271}
%
% \changes{v1.0}{20 Sep 96}{First officially released version.}
% \changes{v1.1}{18 Jul 97}{Corrected two nasty bugs.}
% \changes{v1.2}{12 Sep 97}{Added exporting of lengths \cs{topmargin}
% and \cs{topskip}.
% Added comment on \cs{ExportLength}.}
% \changes{v1.3}{12 Sep 97, pm}{Typos corrected in documentation, index on 2 columns.}
% \changes{v1.4}{17 Oct 97}{Added optionnal argument to
% \cs{openexport} and \cs{Import} to specify a file extension.
% Added new parameters in \cs{ExportPageLayout}.}
% \changes{v1.5}{18 Oct 97}{Added \cs{ExportParameter}.
% Hence improved \cs{ExportPageLayout}. Added \cs{ExportArrayParams}.}
% \changes{v1.6}{03 Aug 99}{Added LPPL license. Minor corrections.}
% \changes{v1.7}{03 Sep 99}{Added \cs{ExportMuskip}.}
% \changes{v1.8}{16 Oct 2000}{Added \cs{ExportIf}.}
%
% \DoNotIndex{\@Mii,\@Miv,\@cons,\@currlist,\@dblarg,\@dbldeferlist}
% \DoNotIndex{\@dblfloat,\@dottedtocline,\@eha,\@Esphack,\@float}
% \DoNotIndex{\@floatpenalty,\@ifnextchar,\@ifundefined,\@latexerr}
% \DoNotIndex{\@mkboth,\@namedef,\@nameuse,\@parboxrestore,\@spaces}
% \DoNotIndex{\@starttoc,\@tempa,\@tempboxa,\@tempdima,\@warning}
% \DoNotIndex{\addcontentsline,\addtocounter,\advance,\arabic,\bfseries}
% \DoNotIndex{\bgroup,\box,\chapter,\columnwidth,\csname,\def,\dimen,\docdate}
% \DoNotIndex{\edef,\egroup,\else,\endcsname,\endinput,\expandafter,\fi}
% \DoNotIndex{\filedate,\fileversion,\global,\hbadness,\hbox,\hfil,\hrule}
% \DoNotIndex{\hsize,\ht,\if@twocolumn,\ifdim,\iffalse,\ifnum,\iftrue,\ifvbox}
% \DoNotIndex{\ifx,\ignorespaces,\intextsep,\kern,\let,\long,\moveleft,\newbox}
% \DoNotIndex{\newcommand,\newcounter,\newif,\newsavebox,\noexpand,\normalsize}
% \DoNotIndex{\numberline,\PackageError,\PackageWarning,\par,\parindent}
% \DoNotIndex{\penalty,\prevdepth,\protect,\refstepcounter,\relax}
% \DoNotIndex{\renewcommand,\rmfamily,\section,\setbox,\setcounter,\space}
% \DoNotIndex{\textheight,\the,\typeout,\unvbox,\uppercase,\vadjust,\value}
% \DoNotIndex{\vbox,\vrule,\vskip,\vspace,\wd,\z@}
%
% \begin{abstract}
% This package\footnote{%
% \begin{tabular}[t]{l}
% Copyright \copyright\ 1996, 1997, 1998, 1999, 2000, 2001 by\\
% Jean-Pierre F. Drucbert\vphantom{bp}\\
% ONERA/Centre de Toulouse SRI\vphantom{bp}\\
% Office National d'\'Etudes et de Recherches A\'erospatiales\vphantom{bp}\\
% Centre de Toulouse\vphantom{bp}\\
% Service R\'eseaux et Informatique\vphantom{bp}\\
% Complexe Scientifique de Rangueil\vphantom{bp}\\
% \\
% 2, Avenue \'Edouard Belin\vphantom{bp}\\
% BP 4025 F-31055 TOULOUSE CEDEX\vphantom{bp}\\
% FRANCE\vphantom{bp}\\
% \vphantom{bp}\\
% Email: \texttt{drucbert@onecert.fr}\vphantom{bp}\\
% \end{tabular}}
% allows you to export or import the values of various \LaTeX\
% registers like counters and lengths (rigid or rubber). This could be
% useful to fabricate ``composite'' documents or to pass some data
% from a document to another one.
% \end{abstract}
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% \section{The \pkg{export} package}
% This package is designed to transmit data of type \meta{counter} or
% \meta{length} % from a \LaTeX\ document to another. You must be aware
% that this package must be used \emph{with extreme care}.
% The passing of data is done via a file. A first document
% \emph{exports} the data by invoking the following sequence of commands:
% \DescribeMacro{\openexport}
% \DescribeMacro{\closeexport}
% \DescribeMacro{\Export}
% \DescribeMacro{\ExportLength}
% \DescribeMacro{\PreciseExportLength}
% \DescribeMacro{\ExportMuskip}
% \DescribeMacro{\ExportParameter}
% \DescribeMacro{\ExportIf}
% \begin{multicols}{2}\small
% \setlength{\columnseprule}{.4pt}
% \begin{quotation}\ttfamily\noindent
% \bs openexport[\meta{extension}]\{\meta{file}\}\\
% \bs Export\{\meta{counter}\}\\
% \bs Export\{\meta{counter}\}\\
% \qquad.\\
% \qquad.\\
% \qquad.\\
% \bs ExportLength\{\meta{length}\}\\
% \bs PreciseExportLength\{\meta{length}\}\\
% \bs ExportMuskip\{\meta{muskip}\}\\
% \bs ExportParameter\{\meta{parameter}\}\\
% \bs ExportIf\{\meta{ifname}\}\\
% \qquad.\\
% \qquad.\\
% \qquad.\\
% \bs closeexport\\
% \end{quotation}
% \end{multicols}
% \noindent
% where \meta{file} is the file used to carry the data (its name will have
% the \texttt{.xpt} extension by default, but you must not give it here;
% an optionnal argument may be used to specify the extension), \meta{counter}
% is the name of a \LaTeX\ counter % (i.e. one of the well known counters
% \texttt{chapter}, \texttt{section}, \ldots,
% \texttt{equation}, etc.), or a counter you have declared by |\newcounter|.
% Also, % \meta{length} is the name (\emph{without the backslash}) of a
% \LaTeX\ length like % \texttt{parskip} or of a length declared by
% |\newlength|. In the ``importing'' document,
% we will find  a command |\Import{|\meta{file}|}| or
% |\Import[|\meta{extension}|]{|\meta{file}|}|.
% The |\ExportLength| 
% command exports a length expressed in \emph{points} (\texttt{pt})
% which some fractionnal digits (5 is the maximum), while
% |\PreciseExportLength| exports the length expressed in
% \emph{scaled points} units (\texttt{sp}, 65536~\texttt{sp} make a point),
% so it avoids possible rounding errors.
% David Carlisle has pointed out that using that macro with a
% \emph{rubber} length as argument would lose the shrinking and
% stretching parts and that |\ExportLength| does not make
% any rounding error in fact. You can trust him! Always use
% |\ExportLength| in case of doubt.
%
% |\ExportMuskip| is like |\ExportLength| but for a muskip
% register. In fact, you could use |\ExportLength| for a
% muskip register: the two commands are identical, except the
% message written in the \texttt{.log} file. But you can not
% use |\PreciseExportLength| with a muskip register: another
% pretext to not use that superfluous command.
%
% |\ExportParameter| allows you to export parameters defined
% by simple commands, like |\textfraction|. Do not try to export
% complex things. It would nor work, at best, or crash, at worst.
%
% |\ExportIf| allows you to export the state of an ``if''
% condition, i.e. the command |\ExportIf{foo}| will export the state of
% |\iffoo|, just by writing |\foofalse| or |\footrue| in the
% export file.
% \emph{Note that the \meta{ifname} does not contains
% the letters if at the beginning, nor the backslash.}
% 
% \DescribeMacro{\ExportPageLayout}
% If you want to export \emph{all} the dimensions (lengths) describing the
% page layout, just use the |\ExportPageLayout| command. In a standard way,
% you should export only that into a given file, which should
% be imported in the preamble
% of the importing document. This method allows to have two documents with
% similar page layouts.
%
% \DescribeMacro{\ExportArrayParams}
% This macro export the dimensions and parameters related to the
% layout of \texttt{array} and \texttt{tabular} environments.
%
% \subsection{An Example of Application}
% This package is very useful when associated which the \pkg{dvipaste}
% package\,\footnote{This package is now obsoleted by the nice
% package \pkg{grfpaste} from David Carlisle, but the same remarks
% still apply.}, which allows you to prepare rectangular page pieces
% and to ``paste'' these page pieces into your document.
% \textbf{Warning:} if a such pasted piece modifies an imported counter
% or length, you must take account of that alteration in the document
% receiving the pasted piece.
%
% The \pkg{dvipaste.sty} package is now available from CTAN archives,
% in the same directory than the \pkg{export} package. But you
% should get from CTAN the whole directory containing 
% \pkg{dvipaste.tex} is. Get it (and the accompagning files),
% and read the documentation of \pkg{dvipaste}:
% you will also need the \pkg{dvipaste.c} program.
% The \pkg{grfpaste} package is also available from CTAN
% archives; it needs the \pkg{dvipaste.c} program.
% A simple example is described in the next pages.
% \clearpage
% \begin{enumerate}
% \item the main document \texttt{a.tex} exports the counters
% \texttt{equation} and \texttt{chapter}, via the file \texttt{x.xpt},
% toward the document \texttt{b.tex}.
% Adding to that, \texttt{a.tex} imports the labels defined in \texttt{b.tex}
% (using the \pkg{xr} package, from David Carlisle).
% \begin{quotation}\footnotesize
% \unskip\hspace*{-4\parindent}\begin{tabular}{p{\clw}c|cp{\clw}}
% \null\hfill\texttt{a.tex}\hfill\null%
%   &\quad&\quad&\null\hfill\texttt{b.tex}\hfill\null\\\hline
% \verb|\documentclass{article}%|&&&\verb|\documentclass{article}%|\\
% \verb|\usepackage%|&&&\verb|\usepackage%|\\
% \verb|  {...,export,dvipaste,xr,...}|&&&\verb|  {...,export,dvipaste,...}|\\
% \verb|\externaldocument{b}|&&&\\
% \verb|\begin{document}|&&&\verb|\begin{document}|\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \verb|\openexport{x}|&&&\\
% \verb|\Export{equation}|&&&\\
% \verb|\Export{chapter}|&&&\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \verb|\closeexport|&&&\\
% \end{tabular}
% 
% \end{quotation}
%
% \item The document \texttt{b.tex} imports the data contained in
%  the file \texttt{x.xpt},
% i.e. the values of the \texttt{equation} and \texttt{chapter} counters.
% \begin{quotation}\footnotesize
% \unskip\hspace*{-4\parindent}\begin{tabular}{p{\clw}c|cp{\clw}}
% \null\hfill\tt a.tex\hfill\null%
%   &\quad&\quad&\null\hfill\tt b.tex\hfill\null\\\hline
% &&&\verb|\Import{x}|
% \end{tabular}
% 
% \end{quotation}
% 
% \item the it uses this counter in preparing an equation in a logical box:
% \begin{quotation}\footnotesize
% \unskip\hspace*{-4\parindent}\begin{tabular}{p{\clw}c|cp{\clw}}
% \null\hfill\tt a.tex\hfill\null%
%   &\quad&\quad&\null\hfill\tt b.tex\hfill\null\\\hline
% &&&\verb|\setbox0=\hbox{%|\\
% &&&\verb|  \begin{minipage}{\textwidth}|\\
% &&&\verb|\begin{equation}|\\
% &&&\verb|a=b  \label{eq-a}|\\
% &&&\verb|\end{equation}|\\
% &&&\verb|\end{minipage}}|\\
% &&&\verb|\sendout{\box0}|\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% &&&\verb|\end{document}|\\
% \end{tabular}
% 
% \end{quotation}
% 
% \item The document \texttt{a.tex} ``pastes'' the piece created by
% \texttt{b.tex}, then explicitely increments the \texttt{equation}
% counter, since the pasted piece contains an unaccounted equation%
% \footnote{An other, more general, method would be to ``export back''
% the counter via an other file. This method is used when several
% counters are involved.}:
% \begin{quotation}\footnotesize
% \unskip\hspace*{-4\parindent}\begin{tabular}{p{\clw}c|cp{\clw}}
% \null\hfill\tt a.tex\hfill\null%
%   &\quad&\quad&\null\hfill\tt b.tex\hfill\null\\\hline
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \verb|\noindent\paste{b}{1}|&&&\\
% \verb|\stepcounter{equation}|&&&\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \null\hfill$\vdots$\hfill$\vdots$\hfill\null%
%   &&&\null\hfill$\vdots$\hfill$\vdots$\hfill\null\\
% \end{tabular}
% 
% \end{quotation}
% \end{enumerate}
% 
% In fact, the following sequence of actions must be performed here:
% \begin{quote}\sloppy
% \begin{tabular}{lcp{8cm}}
% \textbf{latex b}&\qquad&to create the files \texttt{b.dat}, which
% contain the dimensions of the pieces to ``paste'' and
% \texttt{b.dvi} contains the pieces themselves. But \texttt{b.tex}
% will not be able to import anything, because \texttt{x.xpt} has
% not yet been created;\\
% \textbf{latex a}&&to create \texttt{x.xpt};\\
% \textbf{latex b}&&to create again \texttt{b.dat} with the right
% dimensions and \texttt{b.dvi} containing correct values for
% equation numbers, since importation could be done;\\
% \textbf{latex a}&&to take into account the new dimensions in
% \texttt{b.dat};\\
% \textbf{dvipaste a}&&to ``paste'' into \texttt{a.dvi} the pieces
% coming from \texttt{b.dvi}.
% \end{tabular}
% \end{quote}
% 
% Note that the \pkg{xr} package, from David Carlisle, allows you
% to pass \meta{label} information (i.e. to use |\ref{|\meta{label}|}|
% or |\pageref{|\meta{label}|}|) when the \meta{label} is
% defined by |\label{|\meta{label}|}| in an other \LaTeX\ document.
% 
% \subsection{Figures and Tables}
% \DescribeMacro{\xcaptionf}
% \DescribeMacro{\xcaptiont}
% In the case of a figure or table which is ``pasted'' this way into
% a document \emph{with} its caption, this one will not be present in
% the list of figures or tables. An easy solution is to use a
% |\xcaptionf{|\meta{caption}|}| (or |\xcaptiont{|\meta{caption}|}|
% for a table) command. These commands will increment the figure or
% table counter.
% 
% \subsection{Inserting several pages}
% Sometimes, you will need to separately typeset several pages of a
% document. To accomplish that, you prepare a second document
% containing only the desired pages. This second document
% will need, by exemple, some packages not used in the main document
% (often because they require too much resources). To get correctly
% numbered pages, figures, tables, notes, etc.,
% in the main document and in the secondary document, you just have to
% export the corresponding counters from the main document \emph{before}
% the insertion, to import them at the beginning of the secondary document,
% to export them again (via an other file) at the end of the secondary
% document, and at least to import them (via this second file)
% \emph{after} the insertion into the main document.
% 
% \begin{quotation}\sffamily\noindent
% It will certainly be necessary to transmit the page counter,
% which is named ``\texttt{page}''. You must then add a
% |\clearpage| command \emph{before} the exportation.
% This is mandatory only if the exported value must be used to
% number the page which follows the exportation. Do not export
% the page counter to an auxiliary document in which you are creating
% pieces to be ``pasted'' into your document (in such an auxiliary document,
% the ``page counter'' is in fact counter used to number the 
% pieces to be pasted).
% \end{quotation}
% 
% The insertion is only logical: you will have to do it manually in
% the printed paper sheets, or to use software tools manipulating
% \texttt{.dvi} files (e.g. \textbf{dvidvi}, \textbf{dviselect},
% and  \textbf{dviconcat}). A serious problem subsists:
% if they are sectionning commands and floating elements
% (like figures and tables) with captions in the secondary document,
% what to do to have a correct table of contents, a correct
% list of figures and tables in the main document?
% A similar problem arises for the bibliography. You just need to
% add, in the main document, at the insertion point, a
% command:
% \DescribeMacro{\AddInputInAux}
% \begin{quote}\tt
% \bs AddInputInAux\{\meta{secondary document}.aux\}
% \end{quote}
% and so the \texttt{.aux} file of the secondary document will be
% considered as an auxiliary file (of first or second level) of
% the main document. This method has a small drawback:
% if you declare the main document as an external document
% (as defined by the \pkg{xr} package) of the secondary document
% in order to be able to reference labels of the main document (or
% of parts of it) from the secondary one, you will have to use the
% optionnal argument in the command:
% \begin{quote}\ttfamily
% \bs usepackage\{xr\}\\
% \bs externaldocument[\meta{optiannal arg.}]\{\meta{main document}\}\\
% \bs externaldocument[\meta{optionnal arg.}]\{\meta{part
%     of main document}\}
% \end{quote}
% else the labels in the main document (or parts of it) would be
% considered as defined twice during the processing of the secondary
% document. This happens not often, but if you have this problem, the
% solution is simple but not trivial.
%
% \section{Acknowledgments}
% I must thanks, once more, David Carlisle for his precious comments,
% for the \pkg{grfpaste} package, and his great work on the \pkg{xr} package.
%
% \section{Problems}
% \begin{itemize}
% \item This package is certainly to be used with care; the user
% must understand its mechanism.
% \item I did not found a way to determine automatically the type
%  of a \LaTeX\ register. If it is not defined, you get an error.
% But exporting a register with the wrong type (i.e. a rubber length
% as a counter) may lead to confusion or loss of data.
% \item The documentation is written in a very poor english. Do not
% hesitate to send corrections.
% \item Do not confuse this \pkg{export} package (and its \cs{Import}
% command) with the \pkg{import} package (and its \cs{import} command)
% from Donald Arseneau. The two packages have no relation except
% similarity of names.
% \end{itemize}
%
% \section{To Do}
% \begin{itemize}
% \item Other parameter sets could be exported the same way as the
%  page layout parameters. Ask if you have needs.
% \item Export other kinds of parameters (strings, macros, etc.).
% \item Improve the documentation.
% \end{itemize}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% \StopEventually{\setcounter{IndexColumns}{2}\PrintIndex\PrintChanges}
%
% \clearpage
% \section{Implementation}
%
%    \begin{macrocode}
%<*package>
%    \end{macrocode}
%
% \begin{macro}{\export}
% First, we declare the |\export| write channel:
%    \begin{macrocode}
\newwrite\export
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\openexport}
% The command |\openexport| announce the beginning of a sequence
% of exportations and opens the file which will be used to
% carry the data:
%    \begin{macrocode}
\newcommand{\openexport}[2][xpt]{%
\PackageInfo{export}{\MessageBreak
Exportations into #2.#1.\MessageBreak}%
\immediate\openout\export #2.#1}
%    \end{macrocode}
% The optionnal argument is the extension added to the name of the file.
% Default: \texttt{xpt}. Using an other extension may be useful for 
% package writers needing more specific names.
% \end{macro}
%
% \begin{macro}{\closeexport}
% The command |\closeexport| terminates a sequence of exportations
% by closing the file and announcing. Opening and closing are |\immediate|.
%    \begin{macrocode}
\newcommand{\closeexport}{\immediate\closeout\export%
   \PackageInfo{export}{\MessageBreak
   End of exportations.\MessageBreak}}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\ExportLength}
% And now, the exporting commands. To export a length in points,
% we just use |\the|\meta{length} and write it as an argument of
% a |\setlength| command. This command may be used for rigid
% and rubber lengths, because |\the| gives the shrinking and
% stretching parts of a rubber length.
%    \begin{macrocode}
\newcommand{\ExportLength}[1]{%
\PackageInfo{export}{Exportation of length #1}%
\immediate\write\export{\string\setlength{\csname#1\endcsname}%
   {\the\csname#1\endcsname}}}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\PreciseExportLength}
% But for rigid lengths (for rubber ones, you would lose the
% skrinking and stretching parts), you could use
% |\PreciseExportLength|, which export the length expressed in
% scaled points. The trick is to use |\number| in place of |\the|,
% and adding \texttt{sp} for units.
%    \begin{macrocode}
\newcommand{\PreciseExportLength}[1]{%
\PackageInfo{export}{Precise exportation of length #1}%
\immediate\write\export{\string\setlength{\csname#1\endcsname}%
   {\number\csname#1\endcsname sp}}}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\ExportMuskip}
% To export a muskip in mu-s,
% we just use |\the|\meta{length} and write it as an argument of
% a |\setlength| command.
%    \begin{macrocode}
\newcommand{\ExportMuskip}[1]{%
\PackageInfo{export}{Exportation of muskip #1}%
\immediate\write\export{\string\setlength{\csname#1\endcsname}%
   {\the\csname#1\endcsname}}}
%    \end{macrocode}
% Note that |\ExportLength| works well with muskips, but
% |\PreciceExportLength| does nait and gives an error:
% another reason to not use that superfluous command.
% \end{macro}
%
% \begin{macro}{\Export}
% Exporting a counter is rather trivial, using |\@arabic| to get
% its value from the internal name of the \LaTeX\ counter.
%    \begin{macrocode}
\newcommand{\Export}[1]{%
\PackageInfo{export}{Exportation of counter #1}%
\immediate\write\export{\string\setcounter{#1}%
   {\@arabic\csname c@#1\endcsname}}}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\ExportParameter}
% Exporting a simple parameter is utterly complex: hence
% contorsions with \cs{expandafter} and \cs{noexpand}.
% The \cs{providecommand} should avoid errors.
%    \begin{macrocode}
\newcommand{\ExportParameter}[1]{%
\PackageInfo{export}{Exportation of parameter #1}%
\immediate\write\export%
   {\string\providecommand{\expandafter\noexpand\csname#1\endcsname}%
   {}}
\immediate\write\export%
   {\string\renewcommand{\expandafter\noexpand\csname#1\endcsname}%
   {\csname#1\endcsname}}}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\ExportIf}
% Exporting an ``if'' condition is far from trivial.
% We need to protect the contition name and to
% avoid some expansions.
%    \begin{macrocode}
\newcommand{\ExportIf}[1]{%
\PackageInfo{export}{Exportation of the if condition ``#1''}
\expandafter\csname if#1\endcsname
\immediate\write\export{\expandafter\noexpand\csname #1true\endcsname}
\else
\immediate\write\export{\expandafter\noexpand\csname #1false\endcsname}
\fi}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\Import}
% Importing the data is easy: open the file for reading,
% read it: the |\setcounter| and |\setlength| commands are
% executed, then close it.
%    \begin{macrocode}
\newcommand{\Import}[2][xpt]{%
\PackageInfo{export}{\MessageBreak
Importations from #2.#1\MessageBreak}%
\InputIfFileExists{#2.#1}{\relax}{\relax}}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\xcaptionf}
% Now, the two caption commands. They increment the figure or table counter,
% then call the internal macro |\@xcaption|. We provide |\xcaption| if you
% have other classes of floats.
%    \begin{macrocode}
\def\xcaptionf{\refstepcounter{figure} \@dblarg{\@xcaption{figure}}}
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\xcaptiont}
%    \begin{macrocode}
\def\xcaptiont{\refstepcounter{table} \@dblarg{\@xcaption{table}}}
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\xcaption}
%    \begin{macrocode}
\def\xcaption#1{\refstepcounter{#1} \@dblarg{\@xcaption{#1}}}
%    \end{macrocode}
% \end{macro}
% 
% \begin{macro}{\@xcaption}
%    \begin{macrocode}
\long\def\@xcaption#1[#2]#3{\par\addcontentsline{\csname
  ext@#1\endcsname}{#1}{\protect\numberline{\csname
  the#1\endcsname}{\ignorespaces #2}}%
%  ^^A \begingroup
%  ^^A  \@parboxrestore
%  ^^A  \normalsize
%  ^^A  \@makecaption{\csname fnum@#1\endcsname}{\ignorespaces #3}\par
%  ^^A \endgroup
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\iprotected@write}
% We need these two internal macros for |\AddInputInAux|. They are
% slighty modified copies of similar macros in the \LaTeX\ kernel.
%    \begin{macrocode}
\def\iprotected@write#1#2#3{%
      \begingroup
       \let\thepage\relax
       #2%
       \let\protect\@unexpandable@protect
       \edef\reserved@a{\immediate\write#1{#3}}%
       \reserved@a
      \endgroup
      \if@nobreak\ifvmode\nobreak\fi\fi
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@inputx}
%    \begin{macrocode}
\def\@inputx#1{{\def\bibcite##1##2{\relax}\@input{#1}}}
%    \end{macrocode}
% \end{macro}
%
% This macro write an |\@inputx| of the given file into the \texttt{.aux} file.
% \begin{macro}{\AddInputInAux}
%    \begin{macrocode}
\newcommand{\AddInputInAux}[1]{%
  \iprotected@write\@auxout
      {%
      \let\label\@gobble \let\index\@gobble \let\glossary\@gobble}%
      {\string\@inputx{#1}%
           }%
	   }%
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\ExportPageLayout}
% This macro is just a list of exportations of the lengths defining the
% page layout, because it would be so boring to type all that!
% It also exports some parameters and counters related to page layout
% and float management.
% Note that \cs{mathindent} is exported only if it is defined, i.e. when the 
% \texttt{fleqn} class option is used.
%    \begin{macrocode}
\newcommand{\ExportPageLayout}{%
\PackageInfo{export}{\MessageBreak
Exportation of the PageLayout\MessageBreak}%
\PreciseExportLength{hsize}
\PreciseExportLength{vsize}
\PreciseExportLength{hoffset}
\PreciseExportLength{voffset}
\PreciseExportLength{linewidth}
\PreciseExportLength{columnwidth}
\PreciseExportLength{columnsep}
\PreciseExportLength{columnseprule}
\PreciseExportLength{parindent}
\ExportLength{parskip}
\PreciseExportLength{hoffset}
\PreciseExportLength{voffset}
\PreciseExportLength{oddsidemargin}
\PreciseExportLength{evensidemargin}
\PreciseExportLength{headheight}
\PreciseExportLength{headsep}
\PreciseExportLength{textheight}
\PreciseExportLength{textwidth}
\PreciseExportLength{paperheight}
\PreciseExportLength{paperwidth}
\PreciseExportLength{marginparsep}
\PreciseExportLength{marginparwidth}
\PreciseExportLength{marginparpush}
\PreciseExportLength{footskip}
\PreciseExportLength{topmargin}
\PreciseExportLength{topskip}
\PreciseExportLength{jot}
\@ifundefined{mathindent}{}{\PreciseExportLength{mathindent}}
\ExportLength{abovedisplayskip}
\ExportLength{belowdisplayskip}
\ExportLength{abovedisplayshortskip}
\ExportLength{belowdisplayshortskip}
\ExportLength{floatsep}
\ExportLength{textfloatsep}
\ExportLength{dblfloatsep}
\ExportLength{dbltextfloatsep}
\ExportLength{intextsep}
\Export{topnumber}
\Export{dbltopnumber}
\Export{bottomnumber}
\Export{totalnumber}
\PreciseExportLength{footnotesep}
\ExportParameter{topfraction}
\ExportParameter{bottomfraction}
\ExportParameter{textfraction}
\ExportParameter{floatpagefraction}
\ExportParameter{dbltopfraction}
\ExportParameter{dblfloatfraction}
\ExportLength{baselineskip}
\ExportLength{normalbaselineskip}
\ExportParameter{baselinestretch}
\PackageInfo{export}{\MessageBreak
End of exportation of the PageLayout\MessageBreak}}%
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\ExportArrayParams}
% This macro is just a list of exportations of the lengths and
% parameters defining the layout in \texttt{array} and
% \texttt{tabular} environments.
%    \begin{macrocode}
\newcommand{\ExportArrayParams}{%
\PackageInfo{export}{\MessageBreak
Exportation of the ArrayParams\MessageBreak}%
\PreciseExportLength{arraycolsep}
\PreciseExportLength{tabcolsep}
\PreciseExportLength{arrayrulewidth}
\PreciseExportLength{doublerulesep}
\ExportParameter{arraystretch}
\PackageInfo{export}{\MessageBreak
End of exportation of the ArrayParams\MessageBreak}}%
%    \end{macrocode}
% \end{macro}
% \Finale
% \end{document}
\endinput