%% This is TEXTMERG.STY
%% Copyright (C) 1992 by Mike Piff.
%% All rights reserved.
%% Copying of this file is authorized only if
%% you make absolutely no changes to your copy.
%%
%% Dr M. J. Piff
%% University of Sheffield
%% Department of Pure Mathematics
%% Hicks Building
%% Hounsfield Road
%% SHEFFIELD S3 7RH
%% England
%% Janet: m.piff@sheffield.ac.uk

%% Usage
%% \documentstyle[textmerg]{article} %% in LaTeX
%% \input textmerg.sty               %% in non-LaTeX versions of TeX

\immediate\write0{Text Merge style option to LaTeX/plain TeX,
   Mike Piff, 07/31/92 01:57pm}
\def\glet{\global\let}
\newread\MergeFile
\def\InputFile#1{%
   \openin\MergeFile=#1
   \ifeof\MergeFile
   \errmessage{Empty merge file}%
   \closein\MergeFile
   \long\def\MakeTemplate##1{%
      \def\Template{}}%
   \else\GetInput\fi}
\def\GetInput{{\endlinechar=-1
   \global\read\MergeFile to\InputBuffer}}
\def\SeeIfEof{%
   \let\NextLook\relax
   \ifeof\MergeFile
   \else
      \ifx\InputBuffer\empty
         \LookAgain
      \fi
   \fi
   \NextLook}
\def\LookAgain{\GetInput
   \let\NextLook\SeeIfEof}
\newif\ifNonBlank \NonBlankfalse
\def\AllowBlank{\global\NonBlankfalse}
\def\DontAllowBlank{\global\NonBlanktrue}
\def\ReadIn#1{%
   \ifNonBlank\SeeIfEof\fi
   \ifeof\MergeFile
      \gdef#1{??}\MissingField
   \else
      \glet#1\InputBuffer
      \GetInput
   \fi}
\def\MissingField{%
   \message{Missing field in file}}
\newtoks\GlobalFields
\def\Fields#1{\GlobalFields{#1}}
\def\ParseFields#1{%
   \ifx#1\EndParseFields
      \let\NextParse\relax
   \else
      \let\NextParse\ParseFields
      \ifx#1+\DontAllowBlank
      \else
         \ifx#1-\AllowBlank
         \else\ReadIn#1
         \fi
      \fi
   \fi\NextParse}
\let\EndParseFields\ParseFields
\def\ReadFields#1{\expandafter\ParseFields
   \the#1\EndParseFields
   \AllowBlank}
\long\def\Merge#1#2{\begingroup%
   \InputFile{#1}%
   \def\Fields##1{%
      \ParseFields##1\EndParseFields}%
   \MakeTemplate{#2}\Iterate}
\long\def\MakeTemplate#1{\def\Template{#1}}
\countdef\Iteratecounter=9
\Iteratecounter=0
\def\Iterate{%
   \global\advance\Iteratecounter by1
   \ReadFields\GlobalFields
   \Template
   \SeeIfEof
   \ifeof\MergeFile
      \def\NextIteration{%
         \endgroup\closein\MergeFile}%
   \else
      \let\NextIteration\Iterate
   \fi
   \NextIteration}
\newcount\MultiCount \newcount\MaxCount
\newif\ifStartOfList
\def\MultiRead#1{%
   \ifnum#1>0
      \SelectCR
      \MakeEmpty{#1}%
      \global\StartOfListtrue
      \glet\NextRead\MRead
      \AllowBlank
      \global\MaxCount=#1
      \NextRead
   \fi}
\newcount\Emptyctr
\def\MakeEmpty#1{\Emptyctr=0
   \loop
      \advance\Emptyctr by1
      \expandafter\ifx\csname
         pr\the\Emptyctr\endcsname\relax
         \expandafter\glet\csname
            pr\the\Emptyctr\endcsname\empty
      \fi
      \ifnum\Emptyctr<#1
   \repeat}
\def\Process#1#2{%
   \expandafter\def\csname
      pr#1\endcsname##1{#2{##1}}}
\def\MarkEnd#1{\gdef\EndMarker{#1}}
\MarkEnd{}
\newtoks\NextLine \newtoks\NextField
\def\AppendNextField{%
   \global\advance\MultiCount1
   \NextField=\expandafter{\TempField}%
   \edef\Append{\NextLine=
      {\the\NextLine&\csname
         pr\the\MultiCount\endcsname
         {\the\NextField}}}%
   \Append}%%\showthe\NextLine}
\def\SelectCR{%
   \ifx\array\undefined
      \gdef\EndLine{\cr}%
   \else
      \glet\EndLine\\%
   \fi}
\def\FinishLine{%
   \ifStartOfList
      \global\StartOfListfalse
   \else\EndLine\fi}
\def\StopProcessing{%
   \global\MultiCount\MaxCount
   \glet\NextRead\AllowBlank}
\def\MRead{%
   \global\MultiCount=1
   \ReadIn\TempField
   \ifx\TempField\EndMarker
      \StopProcessing
   \else
      \FinishLine
      \NextField=\expandafter{\TempField}%
      \edef\StartLine{\NextLine={\csname
         pr1\endcsname{\the\NextField}}}%
      \StartLine
      \ConstructNextRow
   \fi
   \NextRead}
\def\ConstructNextRow{%
   \loop
      \ReadIn\TempField
      \ifx\TempField\EndMarker
         \glet\TempField\empty
         \StopProcessing
         \MissingField
      \else
         \ifeof\MergeFile
            \glet\TempField\empty
            \StopProcessing
            \MissingField
         \fi
      \fi
      \AppendNextField
      \ifnum\MultiCount<\MaxCount
   \repeat
   \the\NextLine}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Dr M J Piff                      %%  e-mail:
%% Department of Pure Mathematics   %%
%% University of Sheffield          %%  M.Piff@sheffield.ac.uk
%% Hicks Building                   %%
%% Hounsfield Road                  %%  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% SHEFFIELD S3 7RH                 %%  Telephone: SHEFFIELD (0742) 768555
%% England                          %%             Ext. 4431
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%