% \iffalse meta-comment
%
% Copyright
%<*driver>
\documentclass{ltxdoc}
\usepackage{doc}

\def\script#1{\texttt{#1}}
\def\ext#1{\texttt{.#1}}
\def\var#1{\texttt{\$#1}}
\def\entry#1{\texttt{@#1}}
\def\lang#1{\textsc{#1}}
\def\bst#1{\textsf{#1.bst}}
\def\BibTeX{Bib\TeX}

%%%\AtBeginDocument{\CodelineIndex\EnableCrossrefs}
%%%\AtEndDocument{\PrintIndex}
\begin{document} 
 \def\docdate{2009/10/11}
 \def\fileversion{2.20}
 \def\filedate{2009/10/11}
 \DocInput{bibexport.dtx}
\end{document}
%</driver>
% 
% \fi
% \CheckSum{26}
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%%
%
% \title{The \script{bibexport.sh} script}
% \author{Nicolas Markey}
% \date{\filedate}
% \maketitle
% \StopEventually{}
%
% \begin{abstract}
% \script{bibexport.sh} is a small shell script, relying on \BibTeX, that
% extracts entries of one or several \ext{bib} file(s). It will expand
% abbreviations and cross-references, except standard month and journal
% abbreviations. The output is indented as neatly as possible, yielding a
% readable \ext{bib} file even if the original one was not.
% \end{abstract}
%
%
% \section{Exporting \ext{bib} files}
%
% \subsection{Why and how?}
%
% \BibTeX{} aims at allowing for the use of one single \ext{bib} file,
% containing many entries, from which \BibTeX{} extracts only the
% \verb+\cite+d ones. When sending a document to someone else, this
% requires either to send the whole file, or to extract some entries
% from the \ext{bib} file.
%
% \BibTeX{} also has a mechanism for using abbreviations and
% cross-references. When extracting entries of a large \ext{bib} file,
% it can be interesting to develop those abbreviations, in order to get a
% clean, self-contained \ext{bib} file. Also, it may be useful to develop
% cross-references in a \ext{bib} file, independently of any document.
%
% \medskip
% \script{bibexport} can either extract entries that are cited in a document,
% or all the entries of one or several \ext{bib} files. It will always develop
% cross-references and abreviations, except standard abbreviations for months or
% some journals, that are defined in standard \BibTeX{} styles. This script
% uses \BibTeX{}. This has both pros and cons:
% \begin{itemize}
%\item[$+$] it is very simple. Basicaly, the script simply calls \BibTeX{}, and the
% \ext{bst} file just outputs the name and the content of each field. 
%\item[$+$] since it uses \BibTeX, we are sure that it will handle everything
% "properly", \emph{i.e.} in the same way as they will be handled when cited in
% a \LaTeX{} document;
%\item[$=$] \BibTeX{} has some strict limitations (especially "no more than 78 consecutive
% non-space characters") that we must be aware of. On the other hand, any such
% problem occuring within the script would also occur when compiling a
% document;
%\item[$-$] abbreviations and cross-references will \emph{always} be
% developped. It could be argued that this is also a positive point, but
% having the choice would have been better.
%\item[$-$] Many people seem to find \BibTeX's internal language clumsy, and thus
% the script could be difficult to adapt to special needs. However, this is
% \emph{really} not that difficult, as will be explained later on. And please,
% don't hesitate to ask for improvements.
% \end{itemize}
%
% \subsection{Related scripts}
%
% Several other tools exist for achieving this task:
% \begin{itemize}
%\item \verb+aux2bib+, written by Ralf Treinen, relies on \verb+bib2bib+,
% which is a \lang{CaML} program for selecting some entries in one or several \ext{bib}
% files. It does not expand anything, but includes all the necessary
% definitions and entries. 
%\item \verb+bibextract.sh+, by Nelson Beebe. This script uses \lang{awk} for
% extracting some entries out of a \ext{bib} file. It is said to be
% noncompliant with cross-references. 
%\item \bst{subset}, by David Kotz. \bst{export} develops the same ideas (but
% I discovered that only later on). \bst{subset} does not handle
% \entry{preamble}, neither does it "protect" standard abbreviations. 
%\item Probalby some others...
% \end{itemize}
%
% \subsection{Some examples}
%
% \begin{itemize}
%\item extracting \verb+\cite+d references of a document, also including
% cross-references:
%\begin{center}
% \ttfamily bibexport -o {\itshape <result>}.bib {\itshape <file>}.aux
%\end{center}
%\item extracting \verb+\cite+d references of a document, without crossrefs,
% and using a special \ext{bst} file:
%\begin{center}
% \ttfamily bibexport -b {\itshape <style>}.bst -o {\itshape <result>}.bib {\itshape <file>}.aux
%\end{center}
%\item export all the entries of two \ext{bib} files (including crossrefed entries):
%\begin{center}
% \ttfamily bibexport -a -o {\itshape <result>}.bib {\itshape <file1>}.bib {\itshape <file2>}.bib
%\end{center}
%\item export all the entries of two \ext{bib} files (without crossrefs):
%\begin{center}
% \ttfamily bibexport -a -n -o {\itshape <result>}.bib {\itshape <file1>}.bib
% {\itshape <file2>}.bib 
%\end{center}
% In fact, the only difference between this and the previous one is that
% \texttt{crossref} field will be filtered out at the end of the script. 
%\item export all the entries of two \ext{bib} files, using an extra file
% containing cross-referenced entries (which should not be included):
%\begin{center}
% \ttfamily bibexport -a -e {\itshape <crossref>}.bib -n -o {\itshape
% <result>}.bib \textbackslash\par {\itshape <file1>}.bib {\itshape <file2>}.bib 
%\end{center}
%\end{itemize}
%
% \subsection{Exporting extra fields}
%
% By~default, \script{bibexport.sh} exports only "standard" fields
% (those defined and used in \bst{plain}), as~well as a few
% others. It~is very easy to modify it in order to export other fields:
% it~suffices to modify \bst{export} as follows:
% \begin{itemize}
% \item in the \texttt{ENTRY} list, add the name of the field you would
%   like to export. Notice that \texttt{ENTRY} takes three space-separated
%   lists as arguments; you must add extra fields in the first argument
%   (actually, the last two are empty).
% \item in the function \texttt{entry.export.extra}, add a line of the
% form
% \begin{center}
% \ttfamily
% "myfield" myfield field.export
% \end{center}
% where \texttt{myfield} is the name of the extra field you want to
% export.
% \end{itemize}
%
% \subsection*{Acknowledgements}
% I thank \'Eric Colin de Verdi\`ere and Richard Mathar
% for suggesting several improvements or corrections.
%
% \section{The code}
% \subsection{The shell script}
% \subsubsection{Initialization}
%
%\begin{macro}{usage()}
% We first define how the script should be used:
%    \begin{macrocode}
%<*script>
function usage()
{
echo "bibexport: a tool to extract BibTeX entries out of .bib files.
usage: $0 [-h|v] [-n] [-b bst] [-a [-e file]...] [-o file] file...
  -a, --all              export the entire .bib files
  -b, --bst              specifies the .bst style file [default: export.bst]
  -c, --crossref         include entries that are crossref'd  [default: yes]
  -e file, --extra file  extra .bib files to be used (for crossrefs)
  -n, --no-crossref      don't include crossref'd entries      [default: no]
  -o file                write output to file       [default: bibexport.bib]
  -p, --preamble         write a preamble at beginning of output
  -t, --terse            operate silently
  -h, --help             print this message and exit
  -v, --version          print version number and exit";
exit 0;
}
%</script>
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}{VERSION}
%\begin{macro}{VDATE}
%\begin{macro}{CREF}
%\begin{macro}{FILE}
%\begin{macro}{EXT}
%\begin{macro}{EXTRA}
%\begin{macro}{EXTRABIB}
%\begin{macro}{SPACE}
%\begin{macro}{BST}
%\begin{macro}{TERSE}
%\begin{macro}{NOBANNER}
%\begin{macro}{ARGS}
% We define the default value of some variables:
% \begin{itemize}
% \item \var{VERSION}: the version number,
% \item \var{VDATE}: the release date,
% \item \var{CREF}: the value of \verb+-min-crossrefs+,
% \item \var{FILE}: the input file(s),
% \item \var{EXT}: the extension (\ext{aux} or \ext{bib}) of input files,
% \item \var{EXTRA}: list of possible extra \ext{bib} files without extension,
% \item \var{EXTRABIB}: list of possible extra \ext{bib} files with extension,
% \item \var{SPACE}: file name separator (can be \textvisiblespace, comma or empty),
% \item \var{BST}: the \ext{bst} file to be used,
% \item \var{TERSE}: tells \BibTeX{} to run silently, 
% \item \var{NOBANNER}: don't print the initial comment,
% \item \var{ARGS}: the list of aruments passed to \texttt{bibexport.sh}.
% \end{itemize}
%    \begin{macrocode}
%<*script>
VERSION="2.20";
VDATE="2009/10/11";
CROSSREF="1";   
FILE="";
EXT=".aux";
EXTRA="";
EXTRABIB="";
SPACE=" ";
BST="export";
TERSE="";
NOBANNER="true";
ARGS=$@;
%</script>
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
% \subsubsection{Handling arguments}
%
% If no argument have been supplied, we call \script{usage()}.
%
%    \begin{macrocode}
%<*script>
if [ $# -eq 0 ]; then
  usage;
fi
%</script>
%    \end{macrocode}
%
% Otherwise, we enter a \verb+while+-loop for handling the whole list of arguments:
%    \begin{macrocode}
%<*script>
while [ $# != 0 ]; do
        case $1 in
%</script>
%    \end{macrocode}
%\begin{itemize}
%\item \verb+-a+ or \verb+--all+: export all the bibliography. This
% means that we input \ext{bib} files. 
%    \begin{macrocode}
%<*script>
              -a|--all)
                EXT=""; SPACE="";
                shift ;;
%</script>
%    \end{macrocode}
%\item \verb+-b+ or \verb+--bst+: specifies the style file. It seems
% that \BibTeX{} does not like the \texttt{./\textit{style}.bst}
% syntax, and we have to handle that case separately.
%    \begin{macrocode}
%<*script>
            -b|--bst) 
                if [ "`dirname $2`" = "." ]; then
                    DOLLARTWO="`basename $2 .bst`";
                else
                    DOLLARTWO="`dirname $2`/`basename $2 .bst`";
                fi
                BST="${DOLLARTWO}";
                shift 2;;
%</script>
%    \end{macrocode}
%\item \verb+-e+ or \verb+--extra+: when we want to export all the
% entries of a \ext{bib} file, we can specify an extra \ext{bib} file
% that would contain entries that we don't want to export, but that
% are needed, \emph{e.g.} for crossrefs.
%    \begin{macrocode}
%<*script>
            -e|--extra)
                if [ "`dirname $2`" = "." ]; then
                    DOLLARTWO="`basename $2 .bib`";
                else
                    DOLLARTWO="`dirname $2`/`basename $2 .bib`";
                fi
                EXTRA="${EXTRA}${DOLLARTWO},";
                EXTRABIB="${EXTRABIB},${DOLLARTWO}.bib";
                shift 2;;
%</script>
%    \end{macrocode}
%\item \verb+-o+ or \verb+--output+: the name of the output file.
%    \begin{macrocode}
%<*script>
            -o|--output-file)
                if [ "`dirname $2`" = "." ]; then
                    DOLLARTWO="`basename $2 .bib`";
                else
                    DOLLARTWO="`dirname $2`/`basename $2 .bib`";
                fi
                OUTPUT="${DOLLARTWO}.bib";
                shift 2 ;;
%</script>
%    \end{macrocode}
%\item \verb+-c+ or \verb+--crossref+ (or others): this options means
% that we want crossrefs to be included. Note that for any entry,
% field inheritage will be performed.
%    \begin{macrocode}
%<*script>
            -c|--crossref|--crossrefs|--with-crossref|--with-crossrefs)
                CREF="1" ;
                shift ;;
%</script>
%    \end{macrocode}
%\item \verb+-n+ or \verb+--no-crossref+: don't include crossref'ed
% entries. 
%    \begin{macrocode}
%<*script>
            -n|--no-crossref|--without-crossref)
                CREF="20000" ;
                shift ;;
%</script>
%    \end{macrocode}
%\item \verb+-v+ or \verb+--version+ for version number:
%    \begin{macrocode}
%<*script>
            -v|--version)
                echo "This is bibexport v${VERSION} (released ${VDATE})"; exit 0;;
%</script>
%    \end{macrocode}
%\item \verb+-p+ or \verb+--preamble+ for inserting some informations 
% at the beginning of the output file:
%    \begin{macrocode}
%<*script>
            -p|--preamble)
                NOBANNER="false";
                shift ;;
%</script>
%    \end{macrocode}
%\item \verb+-t+ or \verb+--terse+ for asking \BibTeX{} to run silently:
%    \begin{macrocode}
%<*script>
            -t|--terse)
                TERSE=" -terse ";
                shift ;;
%</script>
%    \end{macrocode}
%\item other dash-options are erroneous (except \verb+-h+, but...):
%    \begin{macrocode}
%<*script>
            -*)
                usage;;
%</script>
%    \end{macrocode}
%\item there should only remain file names: we add those names to the
% list of files.
%    \begin{macrocode}
%<*script>
            *)
                if [ "`dirname $1`" = "." ]; then
                    DOLLARONE="`basename $1 ${EXT}`";
                else
                    DOLLARONE="`dirname $1`/`basename $1 ${EXT}`";
                fi
                FILE="${FILE}${SPACE}${DOLLARONE}${EXT}";
                if [ -z "${SPACE}" ]; then 
                    SPACE=",";
                fi;
                shift;;
%</script>
%    \end{macrocode}
% \end{itemize}
% That's all folks:
%    \begin{macrocode}
%<*script>
        esac
done
%</script>
%    \end{macrocode}
% 
% \subsubsection{The core of the script}
%
% We first set the name of the result and intermediary files: 
%    \begin{macrocode}
%<*script>
FINALFILE=${OUTPUT};
if [ ! "${FINALFILE}" ]; then
    FINALFILE="bibexport.bib";
fi
TMPFILE="bibexp.`date +%s`";
%</script>
%    \end{macrocode}
%
% We then create the \ext{aux} file for the main run of \BibTeX. Note
% that this could call \BibTeX, with the \bst{expkeys} file, in the
% case where we want to export all entries of a \ext{bib} file but not
% crossrefs. Note how, in that case, we trick \BibTeX for inputing
% extra files twice: we include then with their short name first (with
% no extension), and then with the full name. We \emph{need} to do that,
% since \verb+string+ abbreviations must be defined first, while
% crossrefs must occur after having been referenced.
%
%    \begin{macrocode}
%<*script>
if [ -z "${EXT}" ]; then
    if [ -z "${EXTRA}" ]; then
        cat > ${TMPFILE}.aux <<EOF
\citation{*}
\bibdata{${FILE}}
\bibstyle{${BST}}
EOF
    else
        cat > ${TMPFILE}.aux <<EOF
\citation{*}
\bibdata{${FILE}}
\bibstyle{expkeys}
EOF
        bibtex -min-crossrefs=${CREF} -terse ${TMPFILE};
        mv -f ${TMPFILE}.bbl ${TMPFILE}.aux;
        cat >> ${TMPFILE}.aux <<EOF
\bibdata{${EXTRA}${FILE}${EXTRABIB}}
\bibstyle{${BST}}
EOF
    fi
else
    cat ${FILE} | sed -e "s/bibstyle{.*}/bibstyle{${BST}}/" > ${TMPFILE}.aux;
fi
%</script>
%    \end{macrocode}
%
% This was the hard part. We now call \BibTeX, clean and rename the
% output file, and remove intermediary files:
%
%    \begin{macrocode}
%<*script>
bibtex -min-crossrefs=${CREF} ${TERSE} ${TMPFILE}
echo "" > ${FINALFILE}
if [ ! "${NOBANNER}" = "true" ]; then
    echo -ne "@comment{generated using bibexport:\n" >> ${FINALFILE}; 
    echo -ne "  creation date:\t`date +\"%c\"`\n" >> ${FINALFILE};
    echo -ne "  command:\t\t$0 ${ARGS}\n" >> ${FINALFILE};
    echo -ne "  bibexport-version:\tv${VERSION} (${VDATE})\n" >> ${FINALFILE};
    echo -ne "  bibexport-maintainer:\tmarkey(at)lsv.ens-cachan.fr\n" >> ${FINALFILE};
    sed -ie "s/}/)/g" ${FINALFILE};
    echo -ne "}\n\n\n" >> ${FINALFILE};
fi
if [ ! "x${CREF}" = "x1" ]; then
    sed -r -e \
        "/^ *[cC][rR][oO][sS][sS][rR][eE][fF] *= *[^,]+,?$/d" \
        ${TMPFILE}.bbl >> ${FINALFILE};
else
    cat ${TMPFILE}.bbl >> ${FINALFILE};
fi
rm -f ${TMPFILE}.bbl ${TMPFILE}.aux ${TMPFILE}.blg
%</script>
%    \end{macrocode}
%
%
% \subsection{The \bst{expkeys} file}
%
% The only role of that file is to export the list of entries to be
% exported. It is used when we export all the entries of \ext{bib}
% files, except those of \emph{extra} \ext{bib} files. 
% Thus:
%    \begin{macrocode}
%<*expkeys>
ENTRY{}{}{}
READ
FUNCTION{export.key}
{
  "\citation{" cite$ "}" * * write$ newline$
}
ITERATE{export.key}
%</expkeys>
%    \end{macrocode}
%
% \subsection{The \bst{export} file}
%
% \subsubsection{Some configuration values}
% \begin{macro}{left.width}
% \begin{macro}{right.width}
% \begin{macro}{url.right.width}
% \begin{macro}{left.short.width}
% \begin{macro}{right.short.width}
% \begin{macro}{left.delim}
% \begin{macro}{right.delim}
% We define here the indentation values, and the field
% delimiters. \emph{short} width are used for \entry{preamble}.
%    \begin{macrocode}
%<*export>
FUNCTION{left.width}{#18}
FUNCTION{right.width}{#55}
FUNCTION{url.right.width}{#61}
FUNCTION{left.short.width}{#10} %% for @preamble
FUNCTION{right.long.width}{#63}
FUNCTION{left.delim}{"{"}
FUNCTION{right.delim}{"}"}
%FUNCTION{left.delim}{quote$}
%FUNCTION{right.delim}{quote$}
%</export>
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
% \subsubsection{Entries}
% We use standard entries here. Of course, more entries could be added
% for special \ext{bib} files. Those extra entries will also have to
% be added in the main exporting function.
% \begin{macro}{ENTRY}
%    \begin{macrocode}
%<*export>
ENTRY{
% Standard fields:
    address
    author
    booktitle
    chapter
    edition
    editor
    howpublished
    institution
    journal
    key
    month
    note
    number
    organization
    pages
    publisher
    school
    series
    title
    type
    volume
    year
% Special (but still somewhat standard) fields (natbib, germbib, ...):
    abstract
    doi
    eid
    isbn
    issn
    language
    url
}{}{}
%</export>
%    \end{macrocode}
% \end{macro}
%
% \subsubsection{Basic functions}
%
% No comment.
%\begin{macro}{or}
%\begin{macro}{and}
%\begin{macro}{not}
%    \begin{macrocode}
%<*export>
FUNCTION{not}
{
    {#0}
    {#1}
  if$
}
FUNCTION{and}
{
    'skip$
    {pop$ #0}
  if$
}
FUNCTION{or}
{
    {pop$ #1}
    'skip$
  if$
}
%</export>
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
% \subsubsection{Splitting strings}
%
% We design functions for splitting strings, so that the final
% \ext{bib} file will be cleanly indented. 
% \begin{macro}{space.complete}
% \begin{macro}{split.string}
% \begin{macro}{split.url}
% \begin{macro}{split name}
%    \begin{macrocode}
%<*export>
INTEGERS{left.length right.length}
STRINGS{ s t }
FUNCTION{space.complete}
{
  'left.length :=
  duplicate$ text.length$ left.length swap$ -
  {duplicate$ #0 >}
    {
      swap$ " " * swap$ #1 -
    }
  while$
  pop$
}
FUNCTION{split.string}
{
  'right.length :=
  duplicate$ right.length #1 + #1 substring$ "" =
    {""}
    {
      's :=
      right.length
      {duplicate$ duplicate$ s swap$ #1 substring$ " " = not and}
        {#1 -}
      while$
      duplicate$ #2 <
        {
          pop$ "    " s * ""
        }
        {
          duplicate$ s swap$ #1 swap$ substring$
          swap$
          s swap$ global.max$ substring$
        }
      if$
    }
  if$
}
FUNCTION{split.url}
{
  'right.length :=
  duplicate$ right.length #1 + #1 substring$ "" =
    {""}
    {
      's :=
      right.length
      {duplicate$ duplicate$ s swap$ #1 substring$ "/" = not and}
        {#1 -}
      while$
      duplicate$ #2 <
        {
          pop$ "    " s * ""
        }
        {
          duplicate$ s swap$ #1 swap$ substring$
          swap$ #1 +
          s swap$ global.max$ substring$
        }
      if$
    }
  if$
}
FUNCTION{split.name}
{
  'right.length :=
  duplicate$ right.length #1 + #1 substring$ "" =
    {""}
    {
      's :=
      right.length
      {duplicate$ duplicate$ s swap$ #5 substring$ " and " = not and}
        {#1 -}
      while$
      duplicate$ #2 <
        {
          pop$ "  " s * ""
        }
        {
          #4 + duplicate$ s swap$ #1 swap$ substring$
          swap$
          s swap$ global.max$ substring$
        }
      if$
    }
  if$
}
%</export>
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \subsubsection{Exporting fields}
% 
% Here, we have four exporting functions, since we also have to deal
% with abbreviations: 
%\begin{macro}{field.export}
%\begin{macro}{abbrv.export}
%\begin{macro}{name.export}
%\begin{macro}{url.export}
%    \begin{macrocode}
%<*export>
FUNCTION{field.export}
{
  duplicate$ missing$
    'skip$
    {
      left.delim swap$ * right.delim *
      swap$
      "  " swap$ * " = " * left.width space.complete
      swap$ "," *
      {duplicate$ "" = not}
        {
          right.width split.string 't :=
          *
          write$ newline$
          "" left.width space.complete t
        }
      while$
    }
  if$
  pop$ pop$
}
FUNCTION{abbrv.export}
{
  duplicate$ missing$
    'skip$
    {
      swap$
      "  " swap$ * " = " * left.width space.complete
      swap$ "," *
      {duplicate$ "" = not}
        {
          right.width split.string 't :=
          *
          write$ newline$
          "" left.width space.complete t
        }
      while$
    }
  if$
  pop$ pop$
}
FUNCTION{name.export}
{
  duplicate$ missing$
    'skip$
    {
      left.delim swap$ * right.delim *
      swap$
      "  " swap$ * " = " * left.width space.complete
      swap$ "," *
      {duplicate$ "" = not}
        {
          right.width split.name 't :=
          *
          write$ newline$
          "" left.width space.complete t
        }
      while$
    }
  if$
  pop$ pop$
}
FUNCTION{url.export}
{
  duplicate$ missing$
    'skip$
    {
      left.delim swap$ * right.delim *
      swap$
      "  " swap$ * " = " * left.width space.complete
      swap$ "," *
      {duplicate$ "" = not}
        {
          url.right.width split.url 't :=
          *
          write$ newline$
          "" left.width space.complete t
        }
      while$
    }
  if$
  pop$ pop$
}
%</export>
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
% \subsubsection{Handling abbreviations}
%
% Abbreviations are difficult to deal with if we wish to still use
% them, since \BibTeX will expand them before we can do anything. All we
% can do is to define them in a special way, in order to be able to get
% back to the abbreviations later on. This is precisely what we do:
%\begin{macro}{jan-dec}
%\begin{macro}{acmcs-tcs}
%\begin{macro}{remove.exports.from.months}
%\begin{macro}{remove.export.from.journal}
%    \begin{macrocode}
%<*export>
MACRO{jan}{"export-jan"}
MACRO{feb}{"export-feb"}
MACRO{mar}{"export-mar"}
MACRO{apr}{"export-apr"}
MACRO{may}{"export-may"}
MACRO{jun}{"export-jun"}
MACRO{jul}{"export-jul"}
MACRO{aug}{"export-aug"}
MACRO{sep}{"export-sep"}
MACRO{oct}{"export-oct"}
MACRO{nov}{"export-nov"}
MACRO{dec}{"export-dec"}
MACRO{acmcs}{"export-acmcs"}
MACRO{acta}{"export-acta"}
MACRO{cacm}{"export-cacm"}
MACRO{ibmjrd}{"export-ibmjrd"}
MACRO{ibmsj}{"export-ibmsj"}
MACRO{ieeese}{"export-ieeese"}
MACRO{ieeetc}{"export-ieeetc"}
MACRO{ieeetcad}{"export-ieeetcad"}
MACRO{ipl}{"export-ipl"}
MACRO{jacm}{"export-jacm"}
MACRO{jcss}{"export-jcss"}
MACRO{scp}{"export-scp"}
MACRO{sicomp}{"export-sicomp"}
MACRO{tocs}{"export-tocs"}
MACRO{tods}{"export-tods"}
MACRO{tog}{"export-tog"}
MACRO{toms}{"export-toms"}
MACRO{toois}{"export-poois"}
MACRO{toplas}{"export-toplas"}
MACRO{tcs}{"export-tcs"}
INTEGERS{ intxt }
FUNCTION{remove.exports.from.months}
{
  #0 'intxt :=
  duplicate$ missing$
    'skip$
    {'t :=
    ""
    {t #1 #1 substring$ "" = not}
      {
      t #1 #7 substring$ "export-" =
        {intxt
           {right.delim * #0 'intxt :=}
           'skip$
         if$
         duplicate$ "" =
           'skip$
           {" # " *}
         if$
         t #8 #3 substring$ *
         t #11 global.max$ substring$ 't :=}
        {intxt
           'skip$
           {duplicate$ "" = 
              {}
              {" # " *}
            if$
            left.delim * #1 'intxt :=}
         if$
         t #1 #1 substring$ *
         t #2 global.max$ substring$ 't :=}
      if$
      }
    while$
    intxt
      {right.delim *}
      'skip$
    if$
    }
  if$
}
FUNCTION{remove.export.from.journals}
{
  duplicate$ missing$
    'skip$
    {
      duplicate$ #1 #7 substring$ "export-" =
        {#8 global.max$ substring$}
        {left.delim swap$
         right.delim * *}
      if$
    }
  if$
}
%</export>
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
% \subsubsection{Now, we export...}
%
% We gather everything. This is were special fields must be added for
% being exported:
%\begin{macro}{entry.export.standard}
%\begin{macro}{entry.export.extra}
%\begin{macro}{entry.export}
%\begin{macro}{export}
%    \begin{macrocode}
%<*export>
FUNCTION{entry.export.standard}
{
  "address" address field.export
  "author" author name.export
  "booktitle" booktitle field.export
  "chapter" chapter field.export
  "crossref" crossref field.export
  "edition" edition field.export
  "editor" editor name.export
  "howpublished" howpublished field.export
  "institution" institution field.export
  "journal" journal remove.export.from.journals abbrv.export
  "key" key field.export
  "month" month remove.exports.from.months abbrv.export
  "note" note field.export
  "number" number field.export
  "organization" organization field.export
  "pages" pages field.export
  "publisher" publisher field.export
  "school" school field.export
  "series" series field.export
  "type" type field.export
  "title" title field.export
  "volume" volume field.export
  "year" year field.export
}
FUNCTION{entry.export.extra}
{
  "abstract" abstract field.export
  "doi" doi field.export
  "eid" eid field.export
  "isbn" isbn field.export
  "issn" issn field.export
  "language" language field.export
  "url" url url.export
}
FUNCTION{entry.export}
{
  entry.export.standard
  entry.export.extra
}
FUNCTION{export}
{
  "@" type$ * "{" * cite$ * "," * write$ newline$
  entry.export
  "}" write$ newline$ newline$
}
%</export>
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
% \subsubsection{Miscellanea}
% We also have to handle preamble, and to define functions for each
% entry type (we won't use them but otherwise, \BibTeX would complain). 
%
%\begin{macro}{preamble}
%\begin{macro}{header}
%\begin{macro}{entries.headers}
%\begin{macro}{article-unpublished}
%    \begin{macrocode}
%<*export>
FUNCTION{preamble}
{
preamble$ duplicate$ "" =
  'pop$
  {
    ",-------------------." write$ newline$
    "|     PREAMBLE      |" write$ newline$
    "`-------------------'" write$ newline$ newline$
    "@preamble{ "  swap$
    quote$ swap$ * quote$ *
    {duplicate$ "" = not}
      {
        right.long.width split.string 't :=
        *
        write$ newline$
        "" left.short.width space.complete t
      }
    while$
    "}" write$ newline$ newline$
    pop$ pop$
  }
if$
}
FUNCTION{header}
{
%"** This file has been automatically generated by bibexport **" 
%write$ newline$
%"** See   http://www.lsv.ens-cachan.fr/~markey/bibla.php    **" 
%write$ newline$
%"** for more informations about bibexport.                  **" 
%write$ newline$
newline$
}
FUNCTION{entries.header}
{
preamble$ "" =
  'skip$
  {
    ",-------------------." write$ newline$
    "|  BIBTEX ENTRIES   |" write$ newline$
    "`-------------------'" write$ newline$ newline$
  }
if$
}
FUNCTION{article}{export}
FUNCTION{book}{export}
FUNCTION{booklet}{export}
FUNCTION{conference}{export}
FUNCTION{habthesis}{export}
FUNCTION{inbook}{export}
FUNCTION{incollection}{export}
FUNCTION{inproceedings}{export}
FUNCTION{journals}{export}
FUNCTION{manual}{export}
FUNCTION{mastersthesis}{export}
FUNCTION{misc}{export}
FUNCTION{phdthesis}{export}
FUNCTION{proceedings}{export}
FUNCTION{techreport}{export}
FUNCTION{unpublished}{export}
%</export>
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
% \subsubsection{Main program}
%
% We now can execute and iterate those functions:
%
%    \begin{macrocode}
%<*export>
READ
EXECUTE{header}
EXECUTE{preamble}
EXECUTE{entries.header}
ITERATE{export}
%</export>
%    \end{macrocode}
%
% \Finale
\endinput
