+ \iffalse; awk '/S[H]ELL1/' lineno.sty|sh;exit;
+ ... see bottom for .tex documentation ...
+
+Macro file lineno.sty for LaTeX: attach line numbers, refer to them.
+ \fi
+\def\fileversion{v4.41} \def\filedate{2005/11/02} %VERSION
+
+%%% Copyright 1995--2003 Stephan I. B"ottcher <boettcher@physik.uni-kiel.de>;
+%%% Copyright 2002--2005 Uwe L"uck, http://www.contact-ednotes.sty.de.vu
+%%% for version 4 and code from former Ednotes bundle
+%%% --author-maintained.
+%%%
+%%% This file can be redistributed and/or modified under
+%%% the terms of the LaTeX Project Public License; either
+%%% version 1.3a of the License, or any later version.
+%%% The latest version of this license is in
+%%% http://www.latex-project.org/lppl.txt
+%%% We did our best to help you, but there is NO WARRANTY.
+%
+%%% $Id: lineno.sty,v 3.14.2.2 2004/09/13 19:30:39 stephan Exp $ %% was v4.00.
+% \title{\texttt{\itshape
+%% %% (UL 2004/10/09:) Italic TT is evil
+%% %% ... or nice front page layout!?
+%%
+% lineno.sty \ \fileversion\ \filedate
+% \unskip}\\\ \\
+% A \LaTeX\ package to attach
+% \\ line numbers to paragraphs
+% \unskip}\author{%
+% Stephan I. B\"ottcher
+% \\ Uwe L\"uck
+% \unskip}\date{%
+% boettcher@physik.uni-kiel.de
+% \\ http://contact-ednotes.sty.de.vu
+%% \\ stephan@nevis.columbia.edu
+%% \\ Stephan.Boettcher@cern.ch
+% \\}
+%
+% \documentclass[a4paper,12pt]{article}%D
+% \usepackage{lineno}%D
+%% %% (New v4.00)
+% \catcode`\_\active\let_~
+%% %% Beware math!? (/New v4.00)
+% \def~{\verb~}
+% \let\lessthan<
+% \catcode`\<\active
+% \def<#1>{$\langle${\itshape#1}\/$\rangle$}
+% \catcode`\|\active
+%% (New v4.1: \tt star; in box anyway.)
+% \def|#1{\ttfamily\string#1}
+%% \def|#1{{\ttfamily\string#1}}
+%% (/New v4.1)
+% \newenvironment{code}
+% {\par\runninglinenumbers
+% \modulolinenumbers[1]%
+% \linenumbersep.3em
+% \footnotesize
+% \def\linenumberfont
+% {\normalfont\tiny\itshape}}
+% {}
+%% %% (New v4.00)
+% {\makeatletter \gdef\scs#1{\texttt
+% {\protect\@backslashchar#1}}}
+% \def\old{\par\footnotesize}
+%% %% (/New v4.00)
+%% %% (New v4.1)
+% {\catcode`\/\active
+% \gdef\path{\begingroup\catcode`\/\active
+% \let/\slash\dopath}
+% \gdef\dopath#1{\slash\unpenalty#1\endgroup}}
+%% %% (/New v4.1)
+%
+% \begin{document}%D
+%% \DocInput{lineno}%D
+% \pagewiselinenumbers
+% \maketitle
+% \pagestyle{headings}
+% \tableofcontents
+% \sloppy
+%
+%% %% New v4.00: `...section{%' + \unskip
+% \section{%
+% Introductions
+%% %% New v4.00: `s'
+% \unskip}
+%
+% (New v4.00) Parts of former first section
+% have been rendered separate subsections for package
+% version_v4.00. (/New v4.00)
+%
+% \subsection{%
+% Introduction to versions $\textrm{v}\lessthan4$
+% \unskip}
+%
+% This package provides line numbers on paragraphs.
+% After \TeX\ has broken a paragraph into lines there will
+% be line numbers attached to them, with the possibility to
+% make references through the \LaTeX\ ~\ref~, ~\pageref~
+% cross reference mechanism. This includes four issues:
+% \begin{itemize}
+% \item attach a line number on each line,
+% \item create references to a line number,
+% \item control line numbering mode,
+% \item count the lines and print the numbers.
+% \end{itemize}
+% The first two points are implemented through patches to
+% the output routine. The third by redefining ~\par~, ~\@par~
+% and ~\@@par~. The counting is easy, as long as you want
+% the line numbers run through the text. If they shall
+% start over at the top of each page, the aux-file as well
+% as \TeX s memory have to carry a load for each counted line.
+%
+% I wrote this package for my wife Petra, who needs it for
+% transcriptions of interviews. This allows her to
+% precisely refer to passages in the text. It works well
+% together with ~\marginpar~s, but not too well with displaymath.
+% ~\footnote~s are a problem, especially when they
+% are split, but we may get there.
+% (New v4.00 UL) Version v4.00 overcomes the problem, I believe.
+% (/UL /New v4.00)
+%
+% lineno.sty works
+% surprisingly well with other packages, for
+% example, ~wrapfig.sty~. So please try if it
+% works with whatever you need, and if it does,
+% please tell me, and if it does not, tell me as
+% well, so I can try to fix it.
+%
+% \subsection{%
+% Introduction to versions v4.00ff. (UL)
+% \unskip}
+%
+% ~lineno.sty~ has been maintained by Stephan until version_v3.14.
+% From version_v4.00 onwards, maintenance is shifting towards
+% Uwe L\"uck (UL), who is the author of v4\dots code and of v4\dots
+% changes in documentation. This came about as follows.
+%
+% Since late 2002, Christian Tapp and Uwe L\"uck have employed
+% ~lineno.sty~ for their ~ednotes.sty~, a package supporting
+% critical editions---cf.
+% \[\mbox{\tt
+% http://ednotes.sty.de.vu
+% \unskip}\]
+% ---while you find ~ednotes.sty~ and surrounding files in
+% CTAN folder \path{macros/latex/contrib/ednotes}.
+%
+% Soon, some weaknesses of ~lineno.sty~ showed up, mainly since
+% Christian's critical editions (using ~ednotes.sty~) needed lots
+% of ~\linelabel~s and footnotes. (These weaknesses are due to
+% weaknesses of \LaTeX's ~\marginpar~ mechanism that Stephan
+% used for ~\linelabel~.) So we changed some ~lineno.sty~
+% definitions in some extra files, which moreover offered new
+% features. We sent these files to Stephan, hoping he would take
+% the changes into ~lineno.sty~. However, he was too short of time.
+%
+% Writing a TUGboat article on Ednotes in 2004, we hoped to
+% reduce the number of files in the Ednotes bundle and so asked
+% Stephan again. Now he generously offered maintenance to me, so
+% I could execute the changes on my own.
+%
+% The improvements are as follows:
+% \begin{itemize}\item
+% [(i)] Footnotes placement approaches intentions better
+% (footnotes formerly liked to pile up at late pages).
+% \item
+% [(ii)] The number of ~\linelabel~s in one paragraph is no longer
+% limited to 18.
+% \item
+% [(iii)] ~\pagebreak~, ~\nopagebreak~, ~\vspace~, and the star
+% and optional versions of ~\\~ work as one would expect
+% (section_\ref{s:MVadj}). %% Added for v4.1
+% \item
+% [(iv)] A command is offered which chooses the first line number
+% to be printed in the margin
+% (subsection_\ref{ss:Mod}). %% Added for v4.1
+% \item
+% [(v)] (New v4.1) \LaTeX\ tabular environments (optionally)
+% get line numbers as well, and you can refer to them in the
+% usual automatic way. (It may be considered a shortcoming that,
+% precisely, \emph{rows} are numbered, not lines.---See
+% subsection_\ref{ss:Tab}.)
+% \item
+% [(vi)] We are moving towards referring to math items
+% (subsection_\ref{ss:MathRef} and the hooks in
+% subsection_\ref{ss:LL}).
+% (/New v4.1)
+% \end{itemize}
+% (Thanks to Stephan for making this possible!)
+%
+%% Unpublish:
+%% You may trace the earlier developments of these changes by
+%% requesting our files ~linenox0.sty~, ~linenox1.sty~, and
+%% ~lnopatch.sty~. Most of our changes have been in ~linenox0.sty~.
+%% Our ~linenox1.sty~ has extended ~linenox0.sty~ for one single
+%% purpose in a not very stable way.
+%%% (See ~\linenumberpar~ below).
+%% ~lnopatch.sty~ has done the first line number thing referred
+%% to in case_(iv) up to now.
+%% (New v4.1)
+%% Case_(v) earlier was provided by our ~edtab02.sty~---now
+%% called ~edtable.sty~.
+%% (/New v4.1)
+%
+% Ednotes moreover profits from Stephan's offer with regard
+% to the documentation of our code which yielded these
+% improvements formerly. This documentation now becomes
+% printable, being part of the ~lineno.sty~ documentation.
+%
+% Of course, Stephan's previous ~lineno.sty~ versions were a great
+% and ingenious work and exhibit greatest \TeX pertise. I never
+% could have done this. I learnt a lot in studying the code when
+% Christian pointed out strange output results and error
+% messages, and there are still large portions of ~lineno.sty~
+% which I don't understand (consider only pagewise numbering of
+% lines). Fortunately, Stephan has offered future help if
+% needed.---My code for attaching line numbers to \emph{tabular
+% environments} (as mentioned above, now still in
+% ~edtable.sty~) %% %% TODO
+% developed from macros which Stephan and Christian experimented
+% with in December 2002. Stephan built the basics.
+% (However, I then became too proud to follow his advice only to
+% use and modify ~longtable.sty~.)
+%
+% There are some issues concerning use of counters on which I
+% don't agree with Stephan and where I would like to change the
+% code if ~lineno.sty~ is ``mine'' as Stephan offered. However,
+% Stephan is afraid of compatibility problems from which, in
+% particular, his wife could suffer in the near future. So he
+% demanded that I change as little as possible for my first
+% version. Instead of executing changes that I plan I just offer
+% my opinions at the single occasions. I hope to get in touch
+% this way with users who consider subtle features vital which I
+% consider strange.
+%
+% On the other hand, the sections on improvements of the
+% implementation have been blown up very much and may be tiring
+% and litte understandable for mere \emph{users}. These users
+% may profit from the present presentation just by jumping to
+% sections_\ref{s:Opts} and_\ref{s:UserCmds}. There is a user's
+% guide ulineno.tex which may be even more helpful, but it has
+% not been updated for a while. %% TODO
+%
+% \subsection{%
+% Availability
+% \unskip}
+%
+% In case you have found the present file otherwise than from
+% CTAN: A recent version and documentation of this package
+% should be available from CTAN folder
+% \path{macros/latex/contrib/lineno}.
+% Or mail to one of the addresses at top of file.
+%
+% \subsection{%
+% Introductory code
+% \unskip}
+%
+% This style option is written for \LaTeXe, November 1994 or later,
+% since we need the ~\protected@write~ macro.
+%
+% (New v4.00) And we use ~\newcommand*~ for
+% controlling length of user macro arguments, which has been
+% available since December 1994.
+%%
+
+\NeedsTeXFormat{LaTeX2e}[1994/12/01]
+%% [1994/11/04]
+\ProvidesPackage{lineno}
+ [\filedate\space line numbers on paragraphs \fileversion]
+% (/New v4.00)
+%%
+%% History of versions:
+%% v1.00 1995/03/31 SIB: first release for Petra's interview transcriptions
+%% v1.01 1995/10/28 SIB: added ~pagewise~ mode
+%% v1.02 1995/11/15 SIB: added ~modulo~ option
+%% v1.03 1995/12/05 SIB: pagewise: try to reduce the hash-size requirements
+%% v2.00 1995/12/06 SIB: .. it works, new user interface
+%% v2.01 1996/09/17 SIB: put into CVS
+%% v2.02 1997/03/17 SIB: add: \@reinserts, for footnotes
+%% v2.04 1998/03/09 SIB: add: linenomath environment
+%% v2.05 1998/04/26 SIB: add: prevgraf test
+%% v2.06 1999/03/02 SIB: LPPL added
+%% v3.00 1999/06/11 SiB: include the extension in the main file
+%% v3.01 1999/08/28 SiB: \@reinserts -> \holdinginserts
+%% v3.02 2000/03/10 SiB: \@LN@output
+%% v3.03 2000/07/01 SiB: \@LN@ExtraLabelItems, hyperref
+%% v3.04 2000/12/17 SiB: longtable compatibility.
+%% v3.05 2001/01/02 SiB: [fleqn] detection.
+%% v3.05a 2001/01/04 SiB: [fleqn] detection reverted for eqnarray.
+%% v3.06 2001/01/17 SiB: [twocolumn] mode support.
+%% v3.07 2001/07/30 SiB: [hyperref] option obsoleted.
+%% v3.08 2001/08/02 SiB: linenomath wrapping for \[ \]
+%% v3.08a 2001/08/04 SiB: linenomath wrapping for \[ \] fixed
+%% v3.08b 2002/01/27 SiB: enquotation typo fix
+%% v3.09 2003/01/14 SIB: hyperref detection fix
+%% v3.10 2003/04/15 FMi: \MakeLineNo fix for deep boxes
+%% v3.10a 2003/11/12 Uwe Lück: \lineref typo fix
+%% v4.00 2004/09/02 UL: included linenox0, linenox1, lnopatch code with
+%% documentation, usually indicated by `New v4.00';
+%% discussions of old code, indicated by `UL';
+%% LPPL v.1 -> LPPL v1.3, `program' -> `file';
+%% first lines with \filedate and \fileversion,
+%% according nawk lines; `November 1994 or later',
+%% some earlier documentation typos (including a few
+%% bad minus signs), { -> {% and } -> \unskip} at
+%% line ends (so, e.g., alignment in TOC works); \scs.
+%% 2004/09/03 UL: removed everything which indicated that the
+%% present file were named `lineno4.sty'.
+%% v4.1 2004/09/19 UL: Inserted Stephan's identification line, removed
+%% some TODOs and remarks from v4.00.
+%% 2004/10/04 UL: Added acknowledgement for Daniel Doherty;
+%% `(New v4.00)' with [|\firstlinenumber]; changed
+%% TODOs; Refining -> Redefining (\vadjust).
+%% 2004/10/05 UL: ednmath0 -> mathrefs; \catcode`\~ -> \active;
+%% \path; refined section on options `mathrefs';
+%% changes in introduction.
+%% 2004/10/06 UL: Changed/removed TODOs, e.g., for edtable.sty.
+%% 2004/10/11 UL: Reminders: linenox0/1/lnopatch.sty obsolete;
+%% \tt star in list of commands.
+%% 2004/10/12 UL: Corrected blank lines in lineno.tex.
+%% 2004/10/19 UL: Fixed minor typos; remark on \if@LN@edtable.
+%% v4.1a 2004/11/07 UL: LPPL v1.3a.
+%% v4.1b 2004/11/13 UL: Comment on \outputpenalty values.
+%% v4.1c 2005/01/10 UL: Contact via http.
+%% v4.11 2005/02/20 UL: Error message with \linelabel when not numbering.
+%% 2005/03/07 UL: Removed \linelabel from ss:Tab heading, consider
+%% marginal line numbers as well, revised ss:Tab.
+%% Added a few lines on missing explanations to
+%% s:UserCmds. Corrected some code alignments.
+%% 2005/03/08 UL: Require recent edtable.sty.
+%%
+
+%% v4.2 2005/03/21 UL: "Physical page" counter works with \include.
+%% 2005/04/17 UL: Raised options section above extensions section
+%% (v4.00 disabled `displaymath' option);
+%% third arg for \@ifundefined{mathindent};
+%% "bunch of options";
+%% 2005/04/24 UL: compatibility with tamefloats; vplref.sty.
+%% 2005/04/25 UL: \number -> \the; wondered -> $$; subsec. appbas;
+%% CrtlLN sec -> subsec.; \newcommand* wherever ...;
+%% doc. on `other output routines' and `addpageno'
+%% (this changed from `varioref').
+%% 2005/04/27 UL: =1\relax -> =\@ne, 0\relax ..., \hb@xt@,
+%% \ifx\@@par\@@@par -> \ifLineNumbers, typos,
+%% \pagestyle{headings}, LaTeX -> \LaTeX.
+%% v4.21 2005/04/28 UL: linenomath section: removed wrong \else's,
+%% \holding...: \thr@@, \@LN@outer@holdins, \global.
+%% v4.22 2005/05/01 UL: \unvbox\@outputbox; \@LN@col without #1,
+%% 2005/05/08 UL: global/local \internall..., \resetl... global,
+%% shortened discussions of this and of \newcounter.
+%% 2005/05/09 UL: corr.: doc. typo, version history, bad lines;
+%% percent; \chardef for modulo,
+%% \value{firstlinenumber}.
+%% v4.3 2005/05/10 UL: \@backslashchar -> \char`\\ in \scs.
+%% 2005/05/11 UL: \linenumbers sets ...outer@holdins; tidied up
+%% documentation regarding earlier versions.
+%% 2005/05/12 UL: `linenomath' without spurious number above;
+%% `displaymath' default; edmac homepage ->
+%% ednotes.sty.de.vu, \endlinenomath without
+%% numbers: no change of \holdinginserts;
+%% \linelabel doesn't go to .aux or mark,
+%% hyperref detected; undone 2005/05/10 (bad mark).
+%% 2005/05/13 UL: Reworked hyperref detection (new subsec.).
+%% 2005/05/15 UL: More typo fixes, corrected terrible confusions in
+%% the discussion (v4.22/v4.3) of \new/\stepcounter;
+%% new subsec. in `Line number ...'; another
+%% implementation of `hyperref' detection.
+%% 2005/05/16 UL: Final minor changes.
+%% v4.31b /06/14 UL: Extended explanation of \firstlinenumbers
+%% and package options; \@LN@ifgreat@critical;
+%% \modulolinenumbers*. Sent to Ednotes.news only.
+%% v4.31 2005/06/15 UL: \modulolinenumbers* with \firstlinenumber{1};
+%% " -> ``/''; more doc. on \firstlinenumber .
+%% 2005/06/20 UL: Typo fix.
+%% 2005/10/01 UL: Warning about \mod...* with pagewise mode.
+%% v4.31a /10/02 UL: Minor changes of appearance of doc., e.g.,
+%% \[ for $$.
+%% v4.32b /10/15 UL: Support for \addvspace; removed comments that
+%% had been invisible already for some time;
+%% made clear with which environments the
+%% linenomath environment is not needed.
+%% v4.32ab /10/15 UL: Observe \if@nobreak with support for \addvspace.
+%% v4.32 2005/10/17 UL: Just made it official and sent it to CTAN.
+%% v4.33b /10/23 UL: \if@nobreak\nobreak\fi -> \nobreak .
+%% v4.33ab /10/24 UL: \LineNoLaTeXOutput without \@tempswafalse;
+%% undid v4.22: \[unv]box\@outputbox (space is OK,
+%% \unvbox pushes short columns down); \@LN@kern@z@ .
+%% v4.4b 2005/10/24 UL: Another tidying-up of the discussion of
+%% \stepcounter{linenumber}; \@LN@screenoff@pen
+%% replaces \@LN@kern@z@, \@LN@depthbox .
+%% v4.4 2005/10/27 UL: Just made official for CTAN.
+%% v4.4a 2005/10/29 UL: Undid change of discussion of
+%% \stepcounter{linenumber} (confusion again).
+%% v4.41 2005/11/02 UL: Raised \CheckCommand*.
+%%
+%% Acknowledgements:
+%% v3.06: Donald Arseneau, pointed to mparhack.sty.
+%% v3.07+: Frank Mittelbach, points out inconsistencies in the
+%% user interface.
+%% v3.10: Frank Mittelbach \MakeLineNo fix for deep boxes
+%% v4.00: Daniel Doherty points out clash of \pagewise... with resetting
+%% page number.
+%% v4.21: Much testing work by Erik Luijten.
+%% v4.3: `displaymath' default by Erik Luijten's suggestion.
+%% v4.31: \modulolinenumbers* is an idea of Hillel Chayim Yisraeli's.
+%% v4.32: Support for \addvspace due to Saravanan M.'s observation.
+%% v4.33: Different support for \addvspace due to bug reports by
+%% Saravanan M.'s and David Josef Dev.
+%% v4.4: David Josef Dev points out that \kern\z@ after a paragraph
+%% tends to place its final baseline wrongly.
+%
+%
+% \section{%
+% Put the line numbers to the lines
+% \unskip}
+%
+% (New v4.00) This section contained the most
+% basic package code previously. For various purposes of
+% version_4\dots, much of these basics have been to be modified.
+% Much of my (UL's) reasoning on these modifications has been to
+% be reported. Sorry, the present section has been blown up
+% awfully thus and contains ramifications that may be difficult
+% to trace. We add some ~\subsection~ commands in order to cope
+% with the new situation. (/New v4.00)
+%
+% \subsection{%
+% Basic code of \texttt{lineno.sty} \scs{output}
+% \unskip}\label{ss:output}
+%
+% The line numbers have to be attached by the output
+% routine. We simply set the ~\interlinepenalty~ to $-100000$.
+% The output routine will be called after each line in the
+% paragraph, except the last, where we trigger by ~\par~.
+% The ~\linenopenalty~ is small enough to compensate a bunch of
+% penalties (e.g., with ~\samepage~).
+%
+% (New v3.04) Longtable uses
+% ~\penalty~$-30000$. The lineno penalty range was
+% shrunk to $-188000 \dots -32000$. (/New v3.04)
+% (New v4.00) New values are listed below (11111f.). (/New v4.00)
+
+\newcount\linenopenalty\linenopenalty=-100000
+
+%% TODO v4.4+:
+% (UL) Hm. It is never needed below
+% that this is a counter. ~\def\linenopenalty{-100000\relax}~
+% would do. (I guess this consumes more memory, but it
+% is more important to save counters than to save memory.)
+% I was frightened by ~-\linenopenalty~ below, but indeed
+% \TeX\ interprets the string ~--100000~ as 100000.
+% Has any user or extension package writer ever called
+% ~\linenopenalty=xxx~, or could I really change this?---The
+% counter is somewhat faster than the macro. Together with the
+% compatibility question this seems to support keeping the
+% counter. (???)
+%% Note that Stephan chose ~\mathchardef~ below,
+%% so his choice above seems to have been deliberate.
+%% <- no point, \mathchardef token is fast.
+% (/UL)
+
+\mathchardef\linenopenaltypar=32000
+
+% So let's make a hook to ~\output~, the direct way. The \LaTeX\
+% macro ~\@reinserts~ puts the footnotes back on the page.
+%
+% (New v3.01) ~\@reinserts~ badly
+% screws up split footnotes. The bottom part is
+% still on the recent contributions list, and the
+% top part will be put back there after the bottom
+% part. Thus, since lineno.sty does not play well
+% with ~\inserts~ anyway, we can safely experiment
+% with ~\holdinginserts~, without making things
+% much worse.
+%
+% Or that's what I thought, but: Just activating
+% ~\holdinginserts~ while doing the ~\par~ will
+% not do the trick: The ~\output~ routine may be
+% called for a real page break before all line
+% numbers are done, and how can we get control
+% over ~\holdinginserts~ at that point?
+%
+% Let's try this: When the ~\output~ routine is
+% run with ~\holdinginserts=3~ for a real page
+% break, then we reset ~\holdinginserts~ and
+% restart ~\output~.
+%
+% Then, again, how do we keep the remaining
+% ~\inserts~ while doing further line numbers?
+%
+% If we find ~\holdinginserts~=$-3$ we activate it again
+% after doing ~\output~. (/New v3.01)
+%
+% (New v3.02) To work with
+% multicol.sty, the original output routine is now
+% called indirectly, instead of being replaced.
+% When multicol.sty changes ~\output~, it is a
+% toks register, not the real thing. (/New v3.02)
+%
+% (New v4.00) Two further complications are added.
+%%
+%% TODO v4.3+: Or three, ~\@nobreakfalse~ after ~\MakeLineNo~
+%% for getting rid of ~\@LN@nopagebreak~.
+% \begin{itemize}\item
+% [(i)] Problems with footnotes formerly resulted from
+% \LaTeX's ~\@reinserts~ in ~\@specialoutput~ which Stephan's
+% ~\linelabel~ called via the ~\marginpar~ mechanism.
+% \item
+% [(ii)] \LaTeX\ commands using ~\vadjust~ formerly didn't work
+% as one would have hoped. The problem is as follows:
+% Printing the line number results from
+% a box that the output routine inserts at the place of the
+% ~\interlinepenalty~. ~\vadjust~ items appear \emph{above} the
+% ~\interlinepenalty~ (\TeX book p._105). So ~\pagebreak~, e.g.,
+% formerly sent the line number to the next page, while the
+% penalty from ~\nopagebreak~ could not tie the following line,
+% since it was screened off by the line number box.---Our trick
+% is putting the ~\vadjust~ items into a list macro from which
+% the output routine transfers them into the vertical list,
+% below the line number box.
+% \end{itemize}
+% In this case_(ii), like in case_(i), footnotes would suffer
+% if ~\holdinginserts~ were non-positive. Indeed, in both
+% cases_(i) and_(ii) we tackle the footnote problem by extending
+% that part of Stephan's output routine that is active when
+% ~\holdinginserts~ is positive. This extension writes the line
+% number ~\newlabel~ to the .aux file (which was formerly done
+% under $~\holdinginserts~=-3$) and handles the ~\vadjust~
+% items.---To trigger ~\output~ and its ~\linelabel~ or, resp.,
+% ~\vadjust~ part, the list of signal penalties started
+% immediately before is increased here (first for ~\linelabel~,
+% second for postponed ~\vadjust~ items):
+
+\mathchardef\@Mllbcodepen=11111
+\mathchardef\@Mppvacodepen=11112
+
+% (/New v4.00) (New v4.2) David Kastrup urges to use a private
+% name instead of ~\the\output~ (LaTeX-L-list). Otherwise an
+% ~\output~ routine loaded later and using ~\newtoks\output~
+% again may get lost entirely. So we change use of ~\@LN@output~,
+% using it for the former purpose. Reference to what appeared
+% with the name of ~\output~ here lasts for a few lines and then
+% is given away.
+
+\let\@tempa\output
+\newtoks\output
+\let\@LN@output\output
+\output=\expandafter{\the\@tempa}
+
+% Now we add two cases to Stephan's output routine. (New v4.00)
+
+\@tempa={%
+% (/New 4.2)
+ \LineNoTest
+ \if@tempswa
+%%
+%% (UL) Learnt that even in def.s blank line means ~\par~.
+%% to leave visual space in present file with having a
+%% blank line neither in present nor in .tex file,
+%% use double comment mark (`%%'). (/UL)
+%%
+% (New v4.00)
+% We insert recognition of waiting ~\linelabel~ items---
+%%
+ \ifnum\outputpenalty=-\@Mllbcodepen
+ \WriteLineNo
+%%
+% ---and of waiting ~\vadjust~ items:
+%%
+ \else
+ \ifnum\outputpenalty=-\@Mppvacodepen
+ \PassVadjustList
+ \else
+%%
+%% Now we give control back to Stephan.
+% (/New v4.00) (New v4.2) Outsource ``Standard'' output
+% ---which occurs so rarely---to subsection_\ref{ss:LLO}:
+%%
+ \LineNoLaTeXOutput
+% (/New v4.2) (New v4.00)
+% Two new ~\fi~s for the ~\linelabel~ and ~\vadjust~ tests---
+%%
+ \fi
+ \fi
+%%
+% ---and the remaining is
+%%%next three lines are
+% Stephan's code again:
+% (/New v4.00)
+%%
+ \else
+ \MakeLineNo
+ \fi
+ }
+
+% (New v4.00) Our new macros
+% ~\WriteLineNo~ and ~\PassVadjustList~ will be dealt with in
+% sections_\ref{s:LNref} and_\ref{ss:PVadj}. (/New v4.00)
+%
+% \subsection{%
+% \scs{LineNoTest}
+% \unskip}
+%
+% The float mechanism inserts ~\interlinepenalty~s during
+% ~\output~. So carefully reset it before going on. Else
+% we get doubled line numbers on every float placed in
+% horizontal mode, e.g, from ~\linelabel~.
+%
+% Sorry, neither a ~\linelabel~ nor a ~\marginpar~ should
+% insert a penalty, else the following linenumber
+% could go to the next page. Nor should any other
+% float. So let us suppress the ~\interlinepenalty~
+% altogether with the ~\@nobreak~ switch.
+%
+% Since (ltspace.dtx, v1.2p)[1996/07/26], the ~\@nobreaktrue~ does
+% it's job globally. We need to do it locally here.
+
+\def\LineNoTest{%
+ \let\@@par\@@@par
+ \ifnum\interlinepenalty<-\linenopenaltypar
+ \advance\interlinepenalty-\linenopenalty
+ \@LN@nobreaktrue
+ \fi
+ \@tempswatrue
+ \ifnum\outputpenalty>-\linenopenaltypar\else
+ \ifnum\outputpenalty>-188000\relax
+ \@tempswafalse
+ \fi
+ \fi
+ }
+
+\def\@LN@nobreaktrue{\let\if@nobreak\iftrue} % renamed v4.33
+
+% (UL) I thought here were
+% another case of the save stack problem explained in \TeX book,
+% p._301, namely through both local and global changing
+% ~\if@nobreak~. However, ~\@LN@nobreak~ is called during
+% ~\@LN@output~ only, while ~\@nobreaktrue~ is called by \LaTeX's
+% ~\@startsection~ only. The latter never happens during
+% ~\@LN@output~. So there is no local value of ~\if@nobreak~ on
+% save stack when ~\@nobreaktrue~ acts, since ~\the\@LN@output~
+% (where ~\@LN@output~ is a new name for the original ~\output~)
+% is executed within a group (\TeX book p._21).
+%%
+%% 2004/09/19 Removed nonsense here according to Stephan 2004/09/04.
+%%
+% (/UL)
+%
+% \subsection{%
+% Other output routines (v4.2)
+% \unskip}\label{ss:LLO}
+%
+% I had thought of dealing with bad interference of footnotes
+% (and ~\enlargethispage~) with (real) ~\marginpar~s and floats
+% \emph{here}. Yet this is done in
+% \[
+% ~http://~\mbox{[CTAN]}
+% ~/macros/latex/contrib/tamefloats/tameflts.sty~
+% \]
+% now, and I prefer striving for compatibility with the latter.
+% (See there for expanding on the problem.)
+% This requires returning the special absolute value of
+% ~\holdinginserts~ that ~lineno.sty~ finds at the end of a newly
+% typeset paragraph---now done in subsection_\ref{ss:calls}
+% (~\linenumberpar~).
+% The former ~\LineNoHoldInsertsTest~ has been filled into here.
+%% ---`3' is replaced by ~\thr@@~ for a while. ~\thr@@~ is
+%% useful practice since plain \TeX, but Stephan may have been
+%% wise in suspecting that \LaTeX\ once could forsake ~\thr@@~.
+%% The same holds for ~\@M=10000~.
+% Note: when the following code is invoked, we have
+% ~\if@tempswa~_ =_~\iftrue~.
+% WARNING: I am still not sure whether the present code is good
+% for cooperating with other packages that use ~\holdinginserts~.
+
+\def\LineNoLaTeXOutput{%
+ \ifnum \holdinginserts=\thr@@ % v4.33 without \@tempswafalse
+ \global\holdinginserts-\thr@@
+ \unvbox\@cclv
+ \ifnum \outputpenalty=\@M \else \penalty\outputpenalty \fi
+ \else
+ \if@twocolumn \let\@makecol\@LN@makecol \fi
+ \the\@LN@output % finally following David Kastrup's advice.
+ \ifnum \holdinginserts=-\thr@@
+ \global\holdinginserts\thr@@ \fi
+ \fi
+}
+
+% \textit{More on dealing with output routines from other
+% packages:}
+% Since ~lineno.sty~'s output routine is called at least once
+% for each output line, I think it should be in \TeX's
+% original ~\output~, while output routines dealing with
+% building pages and with floats etc.\ should be filled into
+% registers addressed by ~\output~ after ~\newtoks\output~.
+% Therefore \begin{enumerate}
+% \item
+% ~tameflts.sty~ should be loaded \emph{after} ~lineno.sty~;
+% \item
+% if a class changes ~\output~ (APS journal class revtex4,
+% e.g.), ~lineno.sty~ should be loaded by ~\RequirePackage~
+% [here presumably following some options in
+% brackets]~{lineno}~ \emph{preceding} ~\documentclass~.
+% \item
+% If you actually maintain such a class, please consider
+% loading ~lineno.sty~ on some draft option. The bunch of
+% lineno's package options may be a problem, but perhaps the
+% purpose of your class is offering only very few of lineno's
+% options anyway, maybe just one.
+% \end{enumerate}
+% The latter may also be needed with classes that don't follow
+% David Kastrup's rule on changing ~\output~.
+%
+% \subsection{%
+% \scs{MakeLineNo}: Actually attach line number
+% \unskip}\label{ss:MLN}
+%
+% We have to return all the page to the current page, and
+% add a box with the line number, without adding
+% breakpoints, glue or space. The depth of our line number
+% should be equal to the previous depth of the page, in
+% case the page breaks here, and the box has to be moved up
+% by that depth.
+%
+% The ~\interlinepenalty~ comes after the ~\vadjust~ from a
+% ~\linelabel~, so we increment the line number \emph{after}
+% printing it. The macro ~\makeLineNumber~ produces the
+% text of the line number, see section \ref{appearance}.
+%
+% (UL) I needed a while to understand
+% the sentence on incrementing. Correctly: writing the
+% ~\newlabel~ to the .aux file is triggered by the signal
+% penalty that ~\end@float~ inserts via ~\vadjust~.
+% However, this could be changed by our new ~\PostponeVadjust~.
+% After ~\c@linenumber~ has been introduced as a \LaTeX\
+% counter, it might be preferable that it behaved like standard
+% \LaTeX\ counters which are incremented shortly before printing.
+% But this may be of little practical relevance in this case,
+% as ~\c@linenumber~ is driven in a very non-standard
+% way.---However still, this behaviour of ~\c@linenumber~
+% generates a problem with our ~edtable.sty~.
+%% \unskip---Before,
+%% I thought that Stephan had reported his reasoning incorrectly
+%% and rather did this because of his ~\resetlinenumber~ which
+%% initializes ~\c@linenumber~ to 1 instead of 0---the latter is
+%% usual with \LaTeX\ counters. Cf._additional comment at
+%% ~\resetlinenumber~.
+% (/UL).
+%
+% Finally we put in the natural ~\interlinepenalty~, except
+% after the last line.
+%
+% (New v3.10) Frank Mittelbach points out that box255 may be
+% less deep than the last box inside, so he proposes to
+% measure the page depth with ~\boxmaxdepth=\maxdimen~.
+% (/New v3.10)
+%
+% (UL, New v4.00) We also resume the matter of
+% ~\vadjust~ items that was started in section_\ref{ss:output}.
+%
+% \TeX\ puts only nonzero interline
+% penalties into the vertical list (\TeX book p._105), while
+% ~lineno.sty~ formerly replaced the signal interline penalty by
+% something closing with an explicit penalty of the value that
+% the interline penalty would have without ~lineno.sty~.
+% This is usually 0. Now, explicit vertical penalties can be
+% very nasty with respect to ~\nopagebreak~, e.g., a low (even
+% positive) ~\widowpenalty~ may force a widow where you
+% explicitly tried to forbid it by ~\nopagebreak~
+% (see explanation soon below).
+% The ~\nopagebreak~ we create here would never work if all
+% those zero penalties were present.---On
+% the other hand, we cannot just omit Stephan's zero penalties,
+% because \TeX\ puts a penalty of 10000 after what ~lineno.sty~
+% inserts (\TeX book p._125). This penalty must be overridden
+% to allow page breaks between ordinary lines. To revive
+% ~\nopagebreak~, we therefore replace those zero (or low)
+% penalties by penalties that the user demanded by
+% ~\nopagebreak~.---This mechanism is not perfect and does not
+% exactly restore the original \LaTeX\ working of ~\pagebreak~
+% and ~\nopagebreak~. Viz., if there are several vertical
+% penalties after a line which were produced by closely sitting
+% ~\[no]pagebreak~s, without ~lineno.sty~ the lowest penalty would
+% be effective (cf._\TeX book exercise_14.10). Our mechanism, by
+% contrast, chooses the \emph{last} user-set penalty of the line
+% as the effective one. It would not be very difficult to come
+% more close to the original mechanism, but until someone urges
+% us we will cling to the present simple way. You may consider an
+% advantage of the difference between our mechanism and the
+% original one that the user here can actually override low
+% penalties by ~\nopagebreak~, which may be what a lay \LaTeX\
+% user would expect.
+%% ---Zero glue would do instead of zero
+%% penalty! This could make things easier. Maybe next time.
+%% <- v4.4: No, problem with column depth.
+% (/UL, /New v4.00)
+
+\def\MakeLineNo{%
+ \@LN@maybe@normalLineNumber % v4.31
+ \boxmaxdepth\maxdimen\setbox\z@\vbox{\unvbox\@cclv}%
+ \@tempdima\dp\z@ \unvbox\z@
+ \sbox\@tempboxa{\hb@xt@\z@{\makeLineNumber}}%
+%%
+% (New v4.00) Previously,
+% \begin{old}\begin{verbatim}
+% % \stepcounter{linenumber}%
+% \end{verbatim}
+% \end{old}
+%% %% TODO: Still first `\begin{old}'?
+% followed. (Of course, there was no
+% comment mark; I put it there to make
+% reading the actual code easy.)
+%
+% (New v4.22: improved) Why not just
+% \[~\global\advance\c@linenumber\@ne~?\]
+% ~\stepcounter~ additionally resets ``subordinate''
+% counters, but which could these (usefully) be?
+% Again, may be column counters with ~edtable.sty~!?
+%
+% But then, our ~edtable.sty~ and its ~longtable~ option
+% should use it as well. So use a shorthand supporting
+% uniformity. You can even use it as a hook for choosing
+% ~\global\advance\c@linenumber\@ne~ instead of our choice.
+% (/New v4.22)
+%%
+ \stepLineNumber
+%%
+% (New v4.4) Now
+%%
+ \ht\@tempboxa\z@ \@LN@depthbox
+%%
+% appends the box containing the line number without changing
+% ~\prevdepth~---see end of section.
+% Now is the time for inserting the $\dots$ (/New v4.4)
+%% The line number has now been placed (it may be invisible
+%% depending on the modulo feature), so
+%% we can insert the
+% ~\vadjust~ items. We cannot do this much later, because
+% their right place is above the artificial interline
+% penalty which Stephan's code will soon insert
+% (cf._\TeX book p._105). The next command is just ~\relax~
+% if no ~\vadjust~ items have been accumulated for the
+% current line. Otherwise it is a list macro inserting
+% the ~\vadjust~ items and finally resetting itself.
+% (This is made in section_\ref{ss:PVadj} below.)
+% If the final item is a penalty, it is stored so it can
+% compete with other things about page breaking.
+%%
+ \@LN@do@vadjusts
+ \count@\lastpenalty
+%%
+% At this place,
+% \begin{old}\begin{verbatim}
+% % \ifnum\outputpenalty=-\linenopenaltypar\else
+% \end{verbatim}
+% \end{old}
+% originally followed. We need something \emph{before} the
+% ~\else~:
+%%
+ \ifnum\outputpenalty=-\linenopenaltypar
+ \ifnum\count@=\z@ \else
+%%
+% So final ~\pagebreak[0]~ or ~\nopagebreak[0]~ has no
+% effect---but this will make a difference after headings only,
+% where nobody should place such a thing anyway.
+%%
+ \xdef\@LN@parpgbrk{%
+ \penalty\the\count@
+ \global\let\noexpand\@LN@parpgbrk
+ \noexpand\@LN@screenoff@pen}% v4.4
+%%
+% That penalty will replace former ~\kern\z@~ in
+% ~\linenumberpar~, see subsection_\ref{ss:calls}.---A
+% few days earlier, I tried to send just a penalty value.
+% However, the ~\kern\z@~ in ~\linenumberpar~ is crucial,
+% as I then found out. See below.---The final penalty is
+% repeated, but this does no harm. (It would not be very
+% difficult to avoid the repeating, but it may even be
+% less efficient.) It may be repeated due to the previous
+% ~\xdef~, but it may be repeated as well below in the
+% present macro where artificial interline penalty is to
+% be overridden.
+%%
+ \fi
+ \else
+%%
+% (/New v4.00)
+%% Corrected code alignment with v4.11.
+ \@tempcnta\outputpenalty
+ \advance\@tempcnta -\linenopenalty
+%%
+% (New v4.00)
+% \begin{old}\begin{verbatim}
+% % \penalty\@tempcnta
+% \end{verbatim}
+% \end{old}
+% followed previously. To give ~\nopagebreak~ a chance,
+% we do
+%% Corrected code alignment with v4.11.
+ \penalty \ifnum\count@<\@tempcnta \@tempcnta \else \count@ \fi
+%%
+% instead.---In ~linenox0.sty~, the ~\else~ thing once was omitted.
+% Sergei Mariev's complaint (thanks!) showed that it is vital
+% (see comment before ~\MakeLineNo~).
+% The remaining ~\fi~ from previous package version closes the
+% ~\ifnum\outputpenalty~\dots
+% (/New v4.00)
+%%
+ \fi
+ }
+
+% (New v4.00)
+
+\newcommand\stepLineNumber{\stepcounter{linenumber}}
+
+% For reason, see use above. (/New v4.00)
+%% %% TODO v4.4+: ~\newcommand~ more often!?
+%
+% (New v4.4) The depth preserving trick is drawn here from
+% ~\MakeLineNo~ because it will be used again in
+% section_\ref{ss:calls}.
+
+\def\@LN@depthbox{%
+ \dp\@tempboxa=\@tempdima
+ \nointerlineskip \kern-\@tempdima \box\@tempboxa}
+
+% (/New v4.4)
+%
+% \section{%
+% Control line numbering
+% \unskip}
+% \subsection{%
+% Inserting \scs{output} calls %% own subsec. v4.4.
+% \unskip}\label{ss:calls}
+% The line numbering is controlled via ~\par~. \LaTeX\
+% saved the \TeX-primitive ~\par~ in ~\@@par~. We push it
+% one level further out, and redefine ~\@@par~ to insert
+% the ~\interlinepenalty~ needed to trigger the
+% line numbering. And we need to allow pagebreaks after a
+% paragraph.
+%
+% New (2.05beta): the prevgraf test. A paragraph that ends with a
+% displayed equation, a ~\noindent\par~ or ~wrapfig.sty~ produce empty
+% paragraphs. These should not get a spurious line number via
+% ~\linenopenaltypar~.
+
+\let\@@@par\@@par
+\newcount\linenoprevgraf
+
+% (UL) And needs ~\linenoprevgraf~
+% to be a counter? Perhaps there may be a paragraph having
+% thousands of lines, so ~\mathchardef~ doesn't suffice (really??).
+%%
+%% %% TODO: limitations of lines per paragraph elsewhere?
+%% %% Signal penalties, e.g.!? ~\deadcycles~!?
+%%
+% A macro ending on ~\relax~ might suffice, but would be
+% somewhat slow. I think I will use ~\mathchardef~ next time.
+% Or has any user used ~\linenoprevgraf~? (/UL)
+
+%% v4.33: changed code alignment for better understanding.
+\def\linenumberpar{%
+ \ifvmode \@@@par \else
+ \ifinner \@@@par \else
+ \xdef\@LN@outer@holdins{\the\holdinginserts}% v4.2
+ \advance \interlinepenalty \linenopenalty
+ \linenoprevgraf \prevgraf
+ \global \holdinginserts \thr@@
+ \@@@par
+ \ifnum\prevgraf>\linenoprevgraf
+ \penalty-\linenopenaltypar
+ \fi
+%%
+% (New v4.00)
+% \begin{old}\begin{verbatim}
+% % \kern\z@
+% \end{verbatim}
+% \end{old}
+% was here previously. What for?
+% According to \TeX book p._125, Stephan's
+% interline penalty is changed into 10000. At the end of a
+% paragraph, the ~\parskip~ would follow that penalty of 10000,
+% so there could be a page break neither at the
+% ~\parskip~ nor at the ~\baselineskip~ (\TeX book p._110)---so
+% there could never be a page break between two paragraphs.
+% So something must screen off the 10000 penalty.
+% Indeed, the ~\kern~ is a place to break.
+% (Stephan once knew this: see `allow pagebreaks' above.)
+%
+% Formerly, I tried to replace ~\kern\z@~ by
+% \begin{old}\begin{verbatim}
+% % \penalty\@LN@parpgpen\relax
+% \end{verbatim}
+% \end{old}
+% ---but this allows a page break after heading. So:
+%%
+ \@LN@parpgbrk
+%%
+%% After heading, ~\kern\z@~ resulting from previous line
+%% (see below) is followed by ~\write~ or ~\penalty10000~,
+%% so causes no page break.
+%
+% These and similar changes were formerly done by ~linenox1.sty~.
+% (/New v4.00)
+%
+% (New v4.4)
+% A ~\belowdisplayskip~ may precede the previous when the paragraph
+% ends on a display-math; or there may be a ~\topsep~ from a list, etc.
+% ~\addvspace~ couldn't take account for it with ~\kern\z@~
+% here. v4.32 therefore moved the space down -- with at least two
+% bad consequences.
+% Moreover, David Josef Dev observes that ~\kern\z@~ may
+% inappropriately yield column depth 0pt.
+% For these reasons, we introduce ~\@LN@screenoff@pen~ below.
+% (/New v4.4)
+%%
+ \global\holdinginserts\@LN@outer@holdins % v4.2
+ \advance\interlinepenalty -\linenopenalty
+ \fi % from \ifinner ... \else
+ \fi} % from \ifvmode ... \else
+
+% (New v4.00, v4.4) Initialize ~\@LN@parpgbrk~, accounting
+% for earlier space and for appropriate columndepth.
+% We use former ~\MakeLineNo~'s depth-preverving trick
+% ~\@LN@depthbox~ again:
+
+\def\@LN@screenoff@pen{%
+ \ifdim\lastskip=\z@
+ \@tempdima\prevdepth \setbox\@tempboxa\null
+ \@LN@depthbox \fi}
+
+\global\let\@LN@parpgbrk\@LN@screenoff@pen
+
+% (/New v4.4, v4.00)
+% \subsection{%
+% Turning on/off %% own subsec. v4.4.
+% \unskip}\label{ss:OnOff}
+% The basic commands to enable and disable line numbers.
+% ~\@par~ and ~\par~ are only touched, when they are ~\let~
+% to ~\@@@par~/~\linenumberpar~. The line number may be
+% reset to 1 with the star-form, or set by an optional
+% argument ~[~<number>~]~.
+%
+% (New v4.00) We add ~\ifLineNumbers~ etc.\ since
+% a number of our new adjustments need to know whether
+% linenumbering is active. This just provides a kind of
+% shorthand for ~\ifx\@@par\linenumberpar~; moreover it is
+% more stable: who knows what may happen to ~\@@par~?---A
+% caveat: ~\ifLineNumbers~ may be wrong. E.g., it may be
+% ~\iffalse~ where it acts, while a ~\linenumbers~ a few
+% lines below---in the same paragraph---brings about that
+% the line where the ~\ifLineNumbers~ appears gets a
+% marginal number.
+%% Better implementation suggested below.
+%%
+% (New v4.3) Just noticed: Such tricks have been
+% disallowed with v4.11, see subsections_\ref{ss:LL}
+% and_\ref{ss:OnOff}.---Moreover, the switching between
+% meanings of ~\linelabel~ for a possible error message
+% as of v4.11 is removed. Speed is difficult to esteem
+% and also depends on applications. Just use the most
+% simple code you find. (/New v4.3)
+
+\newif\ifLineNumbers \LineNumbersfalse
+
+% (/New v4.00)
+
+\def\linenumbers{%
+ \LineNumberstrue % v4.00
+ \xdef\@LN@outer@holdins{\the\holdinginserts}% v4.3
+%%
+% (New v4.3) The previous line is for ~{linenomath}~
+% in a first numbered paragraph. (/New v4.3)
+%%
+ \let\@@par\linenumberpar
+ % \let\linelabel\@LN@linelabel % v4.11, removed v4.3
+ \ifx\@par\@@@par\let\@par\linenumberpar\fi
+ \ifx\par\@@@par\let\par\linenumberpar\fi
+ \@LN@maybe@moduloresume % v4.31
+ \@ifnextchar[{\resetlinenumber}%]
+ {\@ifstar{\resetlinenumber}{}}%
+ }
+
+\def\nolinenumbers{%
+ \LineNumbersfalse % v4.00
+ \let\@@par\@@@par
+ % \let\linelabel\@LN@LLerror % v4.11, removed v4.3
+ \ifx\@par\linenumberpar\let\@par\@@@par\fi
+ \ifx\par\linenumberpar\let\par\@@@par\fi
+ }
+
+% (New v4.00) Moreover, it is useful to switch to
+% ~\nolinenumbers~ in ~\@arrayparboxrestore~. We postpone this
+% to section_\ref{ss:ReDef} where we'll have an appending macro
+% for doing this. (/New v4.00)
+%
+% What happens with a display math? Since ~\par~ is not executed,
+% when breaking the lines before a display, they will not get
+% line numbers. Sorry, but I do not dare to change
+% ~\interlinepenalty~ globally, nor do I want to redefine
+% the display math environments here.
+% \begin{displaymath}
+% display \ math
+% \end{displaymath}
+% See the subsection below, for a wrapper environment to make
+% it work. But that requires to wrap each and every display
+% in your \LaTeX\ source %%.
+%% v4.3:
+% (see option ~displaymath~ in subsections_\ref{ss:v3opts}
+% and_\ref{ss:display} for some relief [UL]).
+%
+% The next two commands are provided to turn on line
+% numbering in a specific mode. Please note the difference:
+% for pagewise numbering, ~\linenumbers~ comes first to
+% inhibit it from seeing optional arguments, since
+% re-/presetting the counter is useless.
+
+\def\pagewiselinenumbers{\linenumbers\setpagewiselinenumbers}
+\def\runninglinenumbers{\setrunninglinenumbers\linenumbers}
+
+% Finally, it is a \LaTeX\ style, so we provide for the use
+% of environments, including the suppression of the
+% following paragraph's indentation.
+%
+%% TODO: v4.4+:
+% (UL) I am drawing the following
+% private thoughts of Stephan's to publicity so that others may
+% think about them---or to remind myself of them in an efficient
+% way. (/UL)
+%% UL changed `%%%' to `% %' below.
+%% TODO: add \par to \linenumbers, if called from an environment. %% v4.3
+%% ToDO: add an \@endpe hack if \linenumbers are turned on
+% \begin{old}\begin{verbatim}
+% % TO DO: add \par to \linenumbers, if called from an environment.
+% % To DO: add an \@endpe hack if \linenumbers are turned on
+% % in horizontal mode. {\par\parskip\z@\noindent} or
+% % something.
+% \end{verbatim}
+% \end{old}
+% (UL) However, I rather think that ~\linenumbers~ and %% v4.31
+% ~\nolinenumbers~ should execute a ~\par~ already. (Then the
+% ~\par~s in the following definitions should be removed.) (/UL)
+
+\@namedef{linenumbers*}{\par\linenumbers*}
+\@namedef{runninglinenumbers*}{\par\runninglinenumbers*}
+
+\def\endlinenumbers{\par\@endpetrue}
+\let\endrunninglinenumbers\endlinenumbers
+\let\endpagewiselinenumbers\endlinenumbers
+\expandafter\let\csname endlinenumbers*\endcsname\endlinenumbers
+\expandafter\let\csname endrunninglinenumbers*\endcsname\endlinenumbers
+\let\endnolinenumbers\endlinenumbers
+
+%
+% \subsection{%
+% Display math
+% \unskip}\label{ss:DM}
+%
+% Now we tackle the problem to get display math working.
+% There are different options.
+% \begin{enumerate}\item[
+% 1.] Precede every display math with a ~\par~.
+% Not too good.
+% \item[
+% 2.] Change ~\interlinepenalty~ and associates globally.
+% Unstable.
+% \item[
+% 3.] Wrap each display math with a ~{linenomath}~
+% environment.
+% \end{enumerate}
+% We'll go for option 3. See if it works:
+% \begin{linenomath}
+% \begin{equation}
+% display \ math
+% \end{equation}
+% \end{linenomath}
+% The star form ~{linenomath*}~ should also number the lines
+% of the display itself,
+% \begin{linenomath*}
+% \begin{eqnarray}
+% multi && line \\
+% display && math \\
+% &
+% \begin{array}{c}
+% with \\
+% array
+% \end{array}
+% &
+% \end{eqnarray}
+% \end{linenomath*}
+% including multline displays.
+%
+% First, here are two macros to turn
+% on linenumbering on paragraphs preceeding displays, with
+% numbering the lines of the display itself, or without.
+% The ~\ifx..~ tests if line numbering is turned on. It
+% does not harm to add these wrappers in sections that are
+% not numbered. Nor does it harm to wrap a display
+% twice, e.q, in case you have some ~{equation}~s wrapped
+% explicitely, and later you redefine ~\equation~ to do it
+% automatically.
+%
+% (New v4.3) To avoid the spurious line number above a
+% display in vmode, I insert ~\ifhmode~. (/New v4.3)
+
+\newcommand\linenomathNonumbers{%
+ \ifLineNumbers
+%% \ifx\@@par\@@@par\else
+ \ifnum\interlinepenalty>-\linenopenaltypar
+ \global\holdinginserts\thr@@
+ \advance\interlinepenalty \linenopenalty
+ \ifhmode % v4.3
+ \advance\predisplaypenalty \linenopenalty
+ \fi
+ \fi
+ \fi
+ \ignorespaces
+ }
+
+\newcommand\linenomathWithnumbers{%
+ \ifLineNumbers
+%% \ifx\@@par\@@@par\else
+ \ifnum\interlinepenalty>-\linenopenaltypar
+ \global\holdinginserts\thr@@
+ \advance\interlinepenalty \linenopenalty
+ \ifhmode % v4.3
+ \advance\predisplaypenalty \linenopenalty
+ \fi
+ \advance\postdisplaypenalty \linenopenalty
+ \advance\interdisplaylinepenalty \linenopenalty
+ \fi
+ \fi
+ \ignorespaces
+ }
+
+% The ~{linenomath}~ environment has two forms, with and
+% without a star. The following two macros define the
+% environment, where the stared/non-stared form does/doesn't number the
+% lines of the display or vice versa.
+
+\newcommand\linenumberdisplaymath{%
+ \def\linenomath{\linenomathWithnumbers}%
+ \@namedef{linenomath*}{\linenomathNonumbers}%
+ }
+
+\newcommand\nolinenumberdisplaymath{%
+ \def\linenomath{\linenomathNonumbers}%
+ \@namedef{linenomath*}{\linenomathWithnumbers}%
+ }
+
+\def\endlinenomath{%
+ \ifLineNumbers % v4.3
+ \global\holdinginserts\@LN@outer@holdins % v4.21
+ \fi
+ \global % v4.21 support for LaTeX2e earlier than 1996/07/26.
+ \@ignoretrue
+}
+\expandafter\let\csname endlinenomath*\endcsname\endlinenomath
+
+% The default is not to number the lines of a display. But
+% the package option ~mathlines~ may be used to switch
+% that behavior.
+
+\nolinenumberdisplaymath
+
+%
+% \section{%
+% Line number references
+% \unskip}\label{s:LNref}
+% \subsection{%
+% Internals %% New subsec. v4.3.
+% \unskip}
+% The only way to get a label to a line number in a
+% paragraph is to ask the output routine to mark it.
+%
+% (New v4.00) The following two paragraphs don't hold any
+% longer, see below. (/New v4.00)
+% \begin{old}\begin{verbatim}
+% % We use the marginpar mechanism to hook to ~\output~ for a
+% % second time. Marginpars are floats with number $-1$, we
+% % fake marginpars with No $-2$. Originally, every negative
+% % numbered float was considered to be a marginpar.
+% %
+% % The float box number ~\@currbox~ is used to transfer the
+% % label name in a macro called ~\@LNL@~<box-number>.
+% \end{verbatim}
+% \end{old}
+% A ~\newlabel~ is written to the aux-file. The reference
+% is to ~\theLineNumber~, \emph{not} ~\thelinenumber~.
+% This allows to hook in, as done below for pagewise line
+% numbering.
+%
+% (New v3.03) The ~\@LN@ExtraLabelItems~ are added for a hook
+% to keep packages like ~{hyperref}~ happy. (/New v3.03)
+%
+% (New v4.00)
+% We fire the ~\marginpar~ mechanism, so we leave \LaTeX's
+% ~\@addmarginpar~ untouched.
+% \begin{old}\begin{verbatim}
+% % \let\@LN@addmarginpar\@addmarginpar
+% % \def\@addmarginpar{%
+% % \ifnum\count\@currbox>-2\relax
+% % \expandafter\@LN@addmarginpar
+% % \else
+% % \@cons\@freelist\@currbox
+% % \protected@write\@auxout{}{%
+% % \string\newlabel
+% % {\csname @LNL@\the\@currbox\endcsname}%
+% % {{\theLineNumber}{\thepage}\@LN@ExtraLabelItems}}%
+% % \fi}
+% \end{verbatim}
+% \end{old}
+% OK, we keep Stephan's ~\@LN@ExtraLabelItems~:
+% (/New v4.00)
+
+\let\@LN@ExtraLabelItems\@empty
+
+% (New v4.00)
+% We imitate the ~\marginpar~ mechanism without using the
+% ~\@freelist~ boxes. ~\linelabel~ will indeed place a signal
+% penalty (~\@Mllbcodepen~, new), and it will put a label into
+% some list macro ~\@LN@labellist~. A new part of the output
+% routine will take the labels from the list and will write
+% ~\newlabel~s to the .aux file.
+%
+% The following is a version of \LaTeX's ~\@xnext~.
+
+\def\@LN@xnext#1\@lt#2\@@#3#4{\def#3{#1}\gdef#4{#2}}
+
+% This takes an item ~#1~ from a list ~#4~ into ~#3~;
+% to be used as ~\expandafter\@LN@xnext#4\@@#3#4~.
+% Our lists use ~\@lt~ after each item for separating.
+% Indeed, there will be another list macro which can
+% appear as argument ~#4~, this will be used for moving
+% ~\vadjust~ items (section_\ref{ss:PVadj}).
+% The list for ~\linelabel~s is the following:
+
+\global\let\@LN@labellist\@empty
+
+% The next is the new part of the output routine writing the
+% ~\newlabel~ to the .aux file. Since it is no real page output,
+% the page is put back to top of the main vertical list.
+
+\def\WriteLineNo{%
+ \unvbox\@cclv
+ \expandafter \@LN@xnext \@LN@labellist \@@
+ \@LN@label \@LN@labellist
+ \protected@write\@auxout{}{\string\newlabel{\@LN@label}%
+ {{\theLineNumber}{\thepage}\@LN@ExtraLabelItems}}%
+}
+
+% (/New v4.00)
+%
+% \subsection{%
+% The \scs{linelabel} command
+% \unskip}\label{ss:LL}
+% To refer to a place in line ~\ref{~<foo>~}~ at page
+% ~\pageref{~<foo>~}~ you place a ~\linelabel{~<foo>~}~ at
+% that place.
+%
+% \linelabel{demo}
+% \marginpar{\tiny\raggedright
+% See if it works: This paragraph
+% starts on page \pageref{demo}, line
+% \ref{demo}.
+% \unskip}%
+% (New v4.11)
+% \begin{old}\begin{verbatim}
+% % If you use this command outside a ~\linenumbers~
+% % paragraph, you will get references to some bogus
+% % line numbers, sorry. But we don't disable the command,
+% % because only the ~\par~ at the end of a paragraph may
+% % decide whether to print line numbers on this paragraph
+% % or not. A ~\linelabel~ may legally appear earlier than
+% % ~\linenumbers~.
+% \end{verbatim}
+% \end{old}
+% This trick is better not allowed---see subsections_\ref{ss:LL}
+% and_\ref{ss:OnOff}.
+% (/New v4.11)
+%
+% ~\linelabel~
+% \begin{old}\begin{verbatim}
+% %, via a fake float number $-2$, %% new mechanism v4.00
+% \end{verbatim}
+% \end{old}
+% puts a
+% ~\penalty~ into a ~\vadjust~, which triggers the
+% pagebuilder after putting the current line to the main
+% vertical list. A ~\write~ is placed on the main vertical
+% list, which prints a reference to the current value of
+% ~\thelinenumber~ and ~\thepage~ at the time of the
+% ~\shipout~.
+%
+% A ~\linelabel~ is allowed only in outer horizontal mode.
+% In outer vertical mode we start a paragraph, and ignore
+% trailing spaces (by fooling ~\@esphack~).
+%
+% (New v4.00) We aim at relaxing the previous condition.
+% We insert a hook ~\@LN@mathhook~ and a shorthand
+% ~\@LN@postlabel~ to support the ~mathrefs~ option which
+% allows ~\linelabel~ in math mode.
+%
+% The next paragraph is no longer valid.
+% \begin{old}\begin{verbatim}
+% % The argument of ~\linelabel~ is put into a macro with a
+% % name derived from the number of the allocated float box.
+% % Much of the rest is dummy float setup.
+% \end{verbatim}
+% \end{old}
+% (/New v4.00)
+%
+% (New v4.11)
+% \begin{old}\begin{verbatim}
+% % \def\linelabel#1{%
+% \end{verbatim}
+% \end{old}
+% I forgot ~\linenumbers~ today, costed me hours or so.
+
+\def\@LN@LLerror{\PackageError{lineno}{%
+ \string\linelabel\space without \string\linenumbers}{%
+ Just see documentation. (New feature v4.11)}\@gobble}
+
+% (New v4.3) Here some things have changed for v4.3.
+% The previous ~#1~ has been replaced by ~\@gobble~.
+% Ensuing, the ~\linelabel~ error message is re-implemented.
+% I find it difficult to compare efficiency of slight
+% alternatives---so choose an easy one. Explicit switching
+% in ~\linenumbers~ and ~\nolinenumbers~ is an additional
+% command that may better be avoided.
+
+\newcommand\linelabel{%
+ \ifLineNumbers \expandafter \@LN@linelabel
+ \else \expandafter \@LN@LLerror \fi}
+%%\let\linelabel\@LN@LLerror
+
+\gdef\@LN@linelabel#1{%
+%%
+% ~\gdef~ for hyperref ``symbolically''. (/New v4.11)
+%%
+ \ifx\protect\@typeset@protect
+%%
+% $\gets$ And a ~\linelabel~ should never be replicated in a
+% mark or a TOC entry. (/New v4.3)
+%%
+ \ifvmode
+ \ifinner \else
+ \leavevmode \@bsphack \@savsk\p@
+ \fi
+ \else
+ \@bsphack
+ \fi
+ \ifhmode
+ \ifinner
+ \@parmoderr
+ \else
+%%
+% (New v4.00)
+%%
+ \@LN@postlabel{#1}%
+% \begin{old}\begin{verbatim}
+% % \@floatpenalty -\@Mii
+% % \@next\@currbox\@freelist
+% % {\global\count\@currbox-2%
+% % \expandafter\gdef\csname @LNL@\the\@currbox\endcsname{#1}}%
+% % {\@floatpenalty\z@ \@fltovf \def\@currbox{\@tempboxa}}%
+% % \begingroup
+% % \setbox\@currbox \color@vbox \vbox \bgroup \end@float
+% % \endgroup
+% % \@ignorefalse \@esphack
+% \end{verbatim}
+% \end{old}
+% (/New v4.00)
+%%
+ \@esphack
+%%
+% (New v4.00)
+% The ~\@ignorefalse~ was appropriate before because the
+% ~\@Esphack~ in ~\end@float~ set ~\@ignoretrue~. Cf._\LaTeX's
+% ~\@xympar~. (/New v4.00)
+%%
+ \fi
+ \else
+%%
+% (New v4.00)
+%%
+ \@LN@mathhook{#1}%
+% \begin{old}\begin{verbatim}
+% % \@parmoderr
+% \end{verbatim}
+% \end{old}
+% Instead of complaining, you may just do your job.
+% (/New v4.00)
+%%
+ \fi
+ \fi
+ }
+
+% (New v4.00) The shorthand just does what happened
+% with ~linenox0.sty~ before ~ednmath0.sty~ (New v4.1:
+% now ~mathrefs~ option) appeared, and
+% the hook is initialized to serve the same purpose.
+% So errors come just where Stephan had built them in,
+% and this is just the \LaTeX\ ~\marginpar~ behaviour.
+
+\def\@LN@postlabel#1{\g@addto@macro\@LN@labellist{#1\@lt}%
+ \vadjust{\penalty-\@Mllbcodepen}}
+\def\@LN@mathhook#1{\@parmoderr}
+
+% (/New v4.00)
+%
+% \modulolinenumbers[3]
+% \firstlinenumber{1}
+% \section{%
+% The appearance of the line numbers
+% \unskip}\label{appearance}
+% \subsection{%
+% Basic code %% own subsec. v4.2.
+% \unskip}
+%
+% The line numbers are set as ~\tiny\sffamily\arabic{linenumber}~,
+% $10pt$ left of the text. With options to place it
+% right of the text, or . . .
+%
+% . . . here are the hooks:
+
+\def\makeLineNumberLeft{%
+ \hss\linenumberfont\LineNumber\hskip\linenumbersep}
+
+\def\makeLineNumberRight{%
+ \linenumberfont\hskip\linenumbersep\hskip\columnwidth
+ \hb@xt@\linenumberwidth{\hss\LineNumber}\hss}
+
+\def\linenumberfont{\normalfont\tiny\sffamily}
+
+\newdimen\linenumbersep
+\newdimen\linenumberwidth
+
+\linenumberwidth=10pt
+\linenumbersep=10pt
+
+% Margin switching requires ~pagewise~ numbering mode, but
+% choosing the left or right margin for the numbers always
+% works.
+
+\def\switchlinenumbers{\@ifstar
+ {\let\makeLineNumberOdd\makeLineNumberRight
+ \let\makeLineNumberEven\makeLineNumberLeft}%
+ {\let\makeLineNumberOdd\makeLineNumberLeft
+ \let\makeLineNumberEven\makeLineNumberRight}%
+ }
+
+\def\setmakelinenumbers#1{\@ifstar
+ {\let\makeLineNumberRunning#1%
+ \let\makeLineNumberOdd#1%
+ \let\makeLineNumberEven#1}%
+ {\ifx\c@linenumber\c@runninglinenumber
+ \let\makeLineNumberRunning#1%
+ \else
+ \let\makeLineNumberOdd#1%
+ \let\makeLineNumberEven#1%
+ \fi}%
+ }
+
+\def\leftlinenumbers{\setmakelinenumbers\makeLineNumberLeft}
+\def\rightlinenumbers{\setmakelinenumbers\makeLineNumberRight}
+
+\leftlinenumbers*
+
+% ~\LineNumber~ is a hook which is used for the modulo stuff.
+% It is the command to use for the line number, when you
+% customize ~\makeLineNumber~. Use ~\thelinenumber~ to
+% change the outfit of the digits.
+%
+%
+% We will implement two modes of operation:
+% \begin{itemize}
+% \item numbers ~running~ through (parts of) the text
+% \item ~pagewise~ numbers starting over with one on top of
+% each page.
+% \end{itemize}
+% Both modes have their own count register, but only one is
+% allocated as a \LaTeX\ counter, with the attached
+% facilities serving both.
+
+\newcounter{linenumber}
+\newcount\c@pagewiselinenumber
+\let\c@runninglinenumber\c@linenumber
+
+% Only the running mode counter may be reset, or preset,
+% for individual paragraphs. The pagewise counter must
+% give a unique anonymous number for each line.
+%
+% (New v4.3) ~\newcounter{linenumber}~
+% was the only ~\newcounter~ in the whole package, and
+% formerly I was near using ~\newcount~ instead. Yet
+% ~\newcounter~ may be quite useful for ~\includeonly~.
+% It also supports resetting ``subcounters'', but what
+% could these be? Well, ~edtable~ might introduce a
+% subcounter for columns.
+% (Note that \LaTeX's setting commands would work with
+% ~\newcount\c@linenumber~ already, apart from this.
+% And perhaps sometimes ~\refstepcounter{linenumber}~
+% wouldn't work---cf._my discussion of ~\stepcounter~ in
+% subsection_\ref{ss:MLN}, similarly ~\refstep...~ would
+% be quite useless.
+% Even the usual redefinitions of ~\thelinenumber~ would
+% work. It is nice, on the other hand, that
+% ~\thelinenumber~ is predefined here. \LaTeX's
+% initialization of the value perhaps just serves making
+% clear \LaTeX\ counters should always be changed
+% globally.---Shortened and improved the discussion here.)
+% (/New v4.3)
+%
+% (New v4.22)
+% ~\c@linenumber~ usually is---globally---incremented by
+% ~\stepcounter~ (at present), so resetting it locally would
+% raise the save stack problem of \TeX book p._301, moreover
+% it would be is useless, there is no hope of keeping the
+% values local (but see subsection_\ref{ss:ILN}). So I insert
+% ~\global~: (/New v4.22)
+
+\newcommand*\resetlinenumber[1][\@ne]{%
+ \global % v4.22
+ \c@runninglinenumber#1\relax}
+
+% (New v4.00)
+% \begin{old}\begin{verbatim}
+% % \newcommand\resetlinenumber[1][1]{\c@runninglinenumber#1}
+% \end{verbatim}
+% \end{old}
+% Added ~\relax~, being quite sure that this does no harm
+% and is quite important, as with ~\setcounter~ etc.
+% I consider this a bug fix (although perhaps no user has
+% ever had a problem with this). (/New v4.00)
+%
+% (v4.22: I had made much fuss about resetting subordinate
+% counters here---removed, somewhat postponed.)
+%
+%% TODO v4.4+:
+%% \newcommand*\resetlinenumber[1][\@ne]{%
+%% \ifx\c@linenumber\c@runninglinenumber
+%% \global\c@linenumber#1\relax
+%% \global\advance\c@linenumber\m@ne
+%% \stepLineNumber
+%% \else
+%% \PackageError{lineno}%% Shorthand!?
+%% {You can't reset line number in pagewise mode}%
+%% {This should suffice.}%
+%% \fi
+%% }
+%
+% \subsection{%
+% Running line numbers
+% \unskip}
+%
+% Running mode is easy, ~\LineNumber~ and ~\theLineNumber~
+% produce ~\thelinenumber~, which defaults to
+% ~\arabic{linenumber}~, using the ~\c@runninglinenumber~
+% counter. This is the default mode of operation.
+
+\def\makeRunningLineNumber{\makeLineNumberRunning}
+
+\def\setrunninglinenumbers{%
+ \def\theLineNumber{\thelinenumber}%
+ \let\c@linenumber\c@runninglinenumber
+ \let\makeLineNumber\makeRunningLineNumber
+ }
+
+\setrunninglinenumbers\resetlinenumber
+
+%
+% \subsection{%
+% Pagewise line numbers
+% \unskip}\label{ss:PW}
+%
+% Difficult, if you think about it. The number has to be
+% printed when there is no means to know on which page it
+% will end up, except through the aux-file. My solution
+% is really expensive, but quite robust.
+%
+% With version ~v2.00~ the hashsize requirements are
+% reduced, because we do not need one controlsequence for
+% each line any more. But this costs some computation time
+% to find out on which page we are.
+%
+% ~\makeLineNumber~ gets a hook to log the line and page
+% number to the aux-file. Another hook tries to find out
+% what the page offset is, and subtracts it from the counter
+% ~\c@linenumber~. Additionally, the switch
+% ~\ifoddNumberedPage~ is set true for odd numbered pages,
+% false otherwise.
+
+\def\setpagewiselinenumbers{%
+ \let\theLineNumber\thePagewiseLineNumber
+ \let\c@linenumber\c@pagewiselinenumber
+ \let\makeLineNumber\makePagewiseLineNumber
+ }
+
+\def\makePagewiseLineNumber{\logtheLineNumber\getLineNumber
+ \ifoddNumberedPage
+ \makeLineNumberOdd
+ \else
+ \makeLineNumberEven
+ \fi
+ }
+
+% Each numbered line gives a line to the aux file
+% \begin{verse}
+% ~\@LN{~<line>~}{~<page>~}~
+% \end{verse}
+% very similar to the ~\newlabel~ business, except that we need
+% an arabic representation of the page number, not what
+% there might else be in ~\thepage~.
+
+\def\logtheLineNumber{\protected@write\@auxout{}{%
+%%
+% (New v4.00) (UL)
+% As Daniel Doherty observed, the earlier line
+% \begin{old}\begin{verbatim}
+% % \string\@LN{\the\c@linenumber}{\noexpand\the\c@page}}}
+% \end{verbatim}
+% \end{old}
+% here may lead into an infinite loop when the user resets
+% the page number (think of ~\pagenumbering~, e.g.).
+% Stephan and I brief\/ly discussed the matter and decided
+% to introduce a ``physical''-page counter to which
+% ~\logtheLineNumber~ refers. It was Stephan's idea to use
+% ~\cl@page~ for reliably augmenting the ``physical''-page
+% counter. However, this relies on the output routine once
+% doing ~\stepcounter{page}~. Before Stephan's
+% suggestion, I had thought of appending the stepping to
+% \LaTeX's ~\@outputpage~.---So the macro definition ends
+% as follows.
+%%
+ \string\@LN{\the\c@linenumber}{%
+%%
+% (New v4.2)
+%% \noexpand\number\n@LN@truepage}}}
+%%
+% The `truepage' counter must start with ~\c@~ so it works
+% with ~\include~, and the ~\@addtoreset~ below is needed
+% for the same purpose.
+%%
+ \noexpand\the\c@LN@truepage}}}
+
+%% \newcount\n@LN@truepage
+%% \g@addto@macro\cl@page{\global\advance\n@LN@truepage\@ne}
+\newcount\c@LN@truepage
+\g@addto@macro\cl@page{\global\advance\c@LN@truepage\@ne}
+\@addtoreset{LN@truepage}{@ckpt}
+
+% (/New v4.2) I had thought of offering more
+% features of a \LaTeX\ counter. However, the user should
+% better \emph{not} have access to this counter. ~\c@page~
+% should suffice as a pagewise master counter.---To be sure,
+% along the present lines the user \emph{can} manipulate
+% ~\c@LN@truepage~ by ~\stepcounter{page}~. E.g., she might
+% do this in order to manually insert a photograph. Well,
+% seems not to harm.
+%
+% The above usage of ~\g@addto@macro~ and ~\cl@page~ may be
+% not as stable as Stephan intended. His proposal used
+% ~\xdef~ directly. But he used ~\cl@page~ as well, and who
+% knows \dots{} And as to ~\g@addto@macro~, I have introduced
+% it for list macros anyway.
+% (/UL) (/New v4.00)
+%
+% From the aux-file we get one macro ~\LN@P~<page> for each
+% page with line numbers on it. This macro calls four other
+% macros with one argument each. These macros are
+% dynamically defined to do tests and actions, to find out
+% on which page the current line number is located.
+%
+% We need sort of a pointer to the first page with line
+% numbers, initiallized to point to nothing:
+
+\def\LastNumberedPage{first}
+\def\LN@Pfirst{\nextLN\relax}
+
+% The four dynamic macros are initiallized to reproduce
+% themselves in an ~\xdef~
+
+\let\lastLN\relax % compare to last line on this page
+\let\firstLN\relax % compare to first line on this page
+\let\pageLN\relax % get the page number, compute the linenumber
+\let\nextLN\relax % move to the next page
+
+% During the end-document run through the aux-files, we
+% disable ~\@LN~. I may put in a check here later, to give
+% a rerun recommendation.
+
+\AtEndDocument{\let\@LN\@gobbletwo}
+
+% Now, this is the tricky part. First of all, the whole
+% definition of ~\@LN~ is grouped, to avoid accumulation
+% on the save stack. Somehow ~\csname~<cs>~\endcsname~ pushes
+% an entry, which stays after an ~\xdef~ to that <cs>.
+%
+% If ~\LN@P~<page> is undefined, initialize it with the
+% current page and line number, with the
+% \emph{pointer-to-the-next-page} pointing to nothing. And
+% the macro for the previous page will be redefined to point
+% to the current one.
+%
+% If the macro for the current page already exists, just
+% redefine the \emph{last-line-number} entry.
+%
+% Finally, save the current page number, to get the pointer to the
+% following page later.
+
+\def\@LN#1#2{{\expandafter\@@LN
+ \csname LN@P#2C\@LN@column\expandafter\endcsname
+ \csname LN@PO#2\endcsname
+ {#1}{#2}}}
+
+\def\@@LN#1#2#3#4{\ifx#1\relax
+ \ifx#2\relax\gdef#2{#3}\fi
+ \expandafter\@@@LN\csname LN@P\LastNumberedPage\endcsname#1%
+ \xdef#1{\lastLN{#3}\firstLN{#3}%
+ \pageLN{#4}{\@LN@column}{#2}\nextLN\relax}%
+ \else
+ \def\lastLN##1{\noexpand\lastLN{#3}}%
+ \xdef#1{#1}%
+ \fi
+ \xdef\LastNumberedPage{#4C\@LN@column}}
+
+% The previous page macro gets its pointer to the
+% current one, replacing the ~\relax~ with the cs-token
+% ~\LN@P~<page>.
+
+\def\@@@LN#1#2{{\def\nextLN##1{\noexpand\nextLN\noexpand#2}%
+ \xdef#1{#1}}}
+
+% Now, to print a line number, we need to find the page,
+% where it resides. This will most probably be the page where
+% the last one came from, or maybe the next page. However, it can
+% be a completely different one. We maintain a cache,
+% which is ~\let~ to the last page's macro. But for now
+% it is initialized to expand ~\LN@first~, where the poiner
+% to the first numbered page has been stored in.
+
+\def\NumberedPageCache{\LN@Pfirst}
+
+% To find out on which page the current ~\c@linenumber~ is,
+% we define the four dynamic macros to do something usefull
+% and execute the current cache macro. ~\lastLN~ is run
+% first, testing if the line number in question may be on a
+% later page. If so, disable ~\firstLN~, and go on to the
+% next page via ~\nextLN~.
+
+\def\testLastNumberedPage#1{\ifnum#1<\c@linenumber
+ \let\firstLN\@gobble
+ \fi}
+
+% Else, if ~\firstLN~ finds out that we need an earlier
+% page, we start over from the beginning. Else, ~\nextLN~
+% will be disabled, and ~\pageLN~ will run
+% ~\gotNumberedPage~ with four arguments: the first line
+% number on this column, the page number, the column
+% number, and the first line on the page.
+
+\def\testFirstNumberedPage#1{\ifnum#1>\c@linenumber
+ \def\nextLN##1{\testNextNumberedPage\LN@Pfirst}%
+ \else
+ \let\nextLN\@gobble
+ \def\pageLN{\gotNumberedPage{#1}}%
+ \fi}
+
+% We start with ~\pageLN~ disabled and ~\nextLN~ defined to
+% continue the search with the next page.
+
+\long\def \@gobblethree #1#2#3{}
+
+\def\testNumberedPage{%
+ \let\lastLN\testLastNumberedPage
+ \let\firstLN\testFirstNumberedPage
+ \let\pageLN\@gobblethree
+ \let\nextLN\testNextNumberedPage
+ \NumberedPageCache
+ }
+
+% When we switch to another page, we first have to make
+% sure that it is there. If we are done with the last
+% page, we probably need to run \TeX\ again, but for the
+% rest of this run, the cache macro will just return four
+% zeros. This saves a lot of time, for example if you have
+% half of an aux-file from an aborted run, in the next run
+% the whole page-list would be searched in vain again and
+% again for the second half of the document.
+%
+% If there is another page, we iterate the search.
+
+\def\testNextNumberedPage#1{\ifx#1\relax
+ \global\def\NumberedPageCache{\gotNumberedPage0000}%
+ \PackageWarningNoLine{lineno}%
+ {Linenumber reference failed,
+ \MessageBreak rerun to get it right}%
+ \else
+ \global\let\NumberedPageCache#1%
+ \fi
+ \testNumberedPage
+ }
+
+% \linelabel{demo2}
+% \marginpar{\tiny\raggedright
+% Let's see if it finds the label
+% on page \pageref{demo},
+% line \ref{demo}, and back here
+% on page \pageref{demo2}, line
+% \ref{demo2}.
+% \unskip}%
+% To separate the official hooks from the internals there is
+% this equivalence, to hook in later for whatever purpose:
+
+\let\getLineNumber\testNumberedPage
+
+% So, now we got the page where the number is on. We
+% establish if we are on an odd or even page, and calculate
+% the final line number to be printed.
+
+\newif\ifoddNumberedPage
+\newif\ifcolumnwiselinenumbers
+\columnwiselinenumbersfalse
+
+\def\gotNumberedPage#1#2#3#4{\oddNumberedPagefalse
+ \ifodd \if@twocolumn #3\else #2\fi\relax\oddNumberedPagetrue\fi
+ \advance\c@linenumber\@ne
+ \ifcolumnwiselinenumbers
+ \subtractlinenumberoffset{#1}%
+ \else
+ \subtractlinenumberoffset{#4}%
+ \fi
+ }
+
+% You might want to run the pagewise mode with running line
+% numbers, or you might not. It's your choice:
+
+\def\runningpagewiselinenumbers{%
+ \let\subtractlinenumberoffset\@gobble
+ }
+
+\def\realpagewiselinenumbers{%
+ \def\subtractlinenumberoffset##1{\advance\c@linenumber-##1\relax}%
+ }
+
+\realpagewiselinenumbers
+
+% For line number references, we need a protected call to
+% the whole procedure, with the requested line number stored
+% in the ~\c@linenumber~ counter. This is what gets printed
+% to the aux-file to make a label:
+
+\def\thePagewiseLineNumber{\protect
+ \getpagewiselinenumber{\the\c@linenumber}}%
+
+% And here is what happens when the label is refered to:
+
+\def\getpagewiselinenumber#1{{%
+ \c@linenumber #1\relax\testNumberedPage
+ \thelinenumber
+ }}
+
+% %
+% A summary of all per line expenses:
+% \begin{description}\item
+% [CPU:] The ~\output~ routine is called for each line,
+% and the page-search is done.
+% \item
+% [DISK:] One line of output to the aux-file for each
+% numbered line
+% \item
+% [MEM:] One macro per page. Great improvement over v1.02,
+% which had one control sequence per line in
+% addition. It blew the hash table after some five
+% thousand lines.
+% \end{description}
+%
+% \subsection{%
+% Twocolumn mode (New v3.06)
+% \unskip}
+%
+% Twocolumn mode requires another patch to the ~\output~
+% routine, in order to print a column tag to the .aux
+% file.
+
+\AtBeginDocument{% v4.2, revtex4.cls (e.g.).
+ % <- TODO v4.4+: Or better in \LineNoLaTeXOutput!?
+ \let\@LN@orig@makecol\@makecol}
+\def\@LN@makecol{%
+ \@LN@orig@makecol
+ \setbox\@outputbox \vbox{%
+ \boxmaxdepth \@maxdepth
+ \protected@write\@auxout{}{%
+ \string\@LN@col{\if@firstcolumn1\else2\fi}%
+ }%
+ \box\@outputbox
+ }% \vbox
+} %% TODO cf. revtexln.sty.
+
+\def\@LN@col{\def\@LN@column} % v4.22, removed #1.
+\@LN@col{1}
+
+%
+% \subsection{%
+% Numbering modulo $m$, starting at $f$
+%% Numbering modulo 5
+% \unskip}\label{ss:Mod}
+%
+% Most users want to have only one in five lines numbered.
+% ~\LineNumber~ is supposed to produce the outfit of the
+% line number attached to the line, while ~\thelinenumber~
+% is used also for references, which should appear even if
+% they are not multiples of five.
+%
+% (New v4.00) Moreover, some users want to
+% control which line number should be printed first. Support
+% of this is now introduced here---see ~\firstlinenumber~
+% below.---~numline.sty~ by Michael Jaegermann and
+% James Fortune offers controlling which \emph{final}
+% line numbers should not be printed. What is
+% it good for? We ignore this here until some user demands
+% it.---Peter Wilson's ~ledmac.sty~ offers much different
+% choices of line numbers to be printed, due to Wayne Sullivan.
+% (/New v4.00)
+%
+% (New v4.22) ~\c@linenumbermodulo~ is rendered a
+% fake counter, as discussed since v4.00. So it can
+% no longer be set by ~\setcounter~. ~\modulolinenumbers~
+% serves this purpose. Well, does anybody want to do
+% what worked with ~\addtocounter~? (Then please tell
+% me.)---At least, ~\value~ still works. For the same
+% purpose I rename the fake `firstlinenumber' counter
+% ~\n@...~ to ~\c@...~. (/New v4.22)
+% \begin{old}\begin{verbatim}
+% % \newcount\c@linenumbermodulo % removed for v4.22
+% \end{verbatim}
+% \end{old}
+%
+%% Removed for v4.22:
+%% (UL) On my question why, e.g.,
+%% ~\chardef~ would not have sufficed, Stephan couldn't remember
+%% exactly; guessed that he wanted to offer \LaTeX\ counter
+%% facilities. However, the typical ones don't come this way.
+%% So I'm quite sure that I will change this next time.
+%%
+%% However, I observed at least two times that users gave a very
+%% high value to ~\c@linenumbermodulo~ in order to suppress
+%% printing of the line number. One of these users preferred an
+%% own way of handling line numbers, just wanted to use
+%% ~\linelabel~ and ~ednotes.sty~ features. Should we support this?
+%% I rather would like to advise them to
+%% ~\let\makeLineNumber\relax~. (/UL)
+%
+% (New v4.00) \par
+% ~\themodulolinenumber~ waits for being declared
+% ~\LineNumber~ by ~\modulolinenumbers~. (This has
+% been so before, no change.) Here is how it
+% looked before:
+% \begin{old}\begin{verbatim}
+% % \def\themodulolinenumber{{\@tempcnta\c@linenumber
+% % \divide\@tempcnta\c@linenumbermodulo
+% % \multiply\@tempcnta\c@linenumbermodulo
+% % \ifnum\@tempcnta=\c@linenumber\thelinenumber\fi
+% % }}
+% \end{verbatim}
+% \end{old}
+% (UL) This was somewhat slow. This arithmetic
+% happens at every line. This time I tend to declare an extra
+%% TODO v4.4+
+% line counter (as opposed to my usual recommendations to use
+% counters as rarely as possible) which is stepped every line.
+% It could be incremented in the same way as ~\c@LN@truepage~
+% is incremented via ~\cl@page~! This is another point in favour
+% of ~{linenumber}~ being a \LaTeX\ counter!
+% When this new counter equals ~\c@linenumbermodulo~, it is reset,
+% and ~\thelinenumber~ is executed.---It gets much slower by my
+% support of controlling the first line number below. I should
+% improve this.---On
+%% %% TODO v4.4+--pagewise!?
+% the other hand, time expense means very little nowadays,
+% while the number of \TeX\ counters still is limited.
+%
+% For the same purpose, moreover, attaching the line number
+% box could be intercepted earlier (in ~\MakeLineNo~),
+% without changing ~\LineNumber~. However, this may be
+% bad for the latter's announcement as a wizard interface
+% in section_\ref{s:UserCmds}.
+%%
+%% I wonder about Stephan's group. Its only effect is that
+%% ~\@tempcnta~ is restored after using it. What for is this?
+%% I tend to remove the group braces. %% TODO v4.4+
+% (/UL)
+%
+% Here is the new code. It is very near to my ~lnopatch.sty~
+% code which introduced the first line number feature
+% before.---I add starting with a ~\relax~ which is so often
+% recommended---without understanding this really. At least,
+% it will not harm.---Former group braces appear as
+% ~\begingroup~/~\endgroup~ here.
+
+\def\themodulolinenumber{\relax
+ \ifnum\c@linenumber<\c@firstlinenumber \else
+ \begingroup
+ \@tempcnta\c@linenumber
+ \advance\@tempcnta-\c@firstlinenumber
+ \divide\@tempcnta\c@linenumbermodulo
+ \multiply\@tempcnta\c@linenumbermodulo
+ \advance\@tempcnta\c@firstlinenumber
+ \ifnum\@tempcnta=\c@linenumber \thelinenumber \fi
+ \endgroup
+ \fi
+}
+
+% (/New v4.00)
+%
+% The user command to set the modulo counter:
+% (New v4.31) \dots\ a star variant is introduced to implement
+% Hillel Chayim Yisraeli's idea to print the first line number
+% after an interruption of the edited text by some editor's
+% text, regardless of the modulo. If it is 1, it is printed only
+% with ~\firstlinenumber{1}~. I.e., you use ~\modulolinenumbers*~
+% for the new feature, without the star you get the simpler
+% behaviour that we have had so far. And you can switch back
+% from the refined behaviour to the simple one by using
+% ~\modulolinenumbers~ without the star.---This enhancement
+% is accompanied by a new package option ~modulo*~ which just
+% executes ~\modulolinenumbers*~
+% (subsection_\ref{ss:v3opts}).---`With ~\firstlinenumber{1}~'
+% exactly means: `1' is printed if and only if the last
+% ~\firstlinenumber~ before or in the paragraph that follows
+% the ``interruption'' has argument `1' (or something
+% \emph{expanding} to `1', or (to) something that \TeX\
+% ``reads'' as 1, e.g.: a \TeX\ count register storing
+% 1).---At present, this behaviour may be unsatisfactory with
+% pagewise line-numbering $\dots$ I'll make an experimental
+% extra package if someone complains \dots
+
+\newcommand\modulolinenumbers{%
+ \@ifstar
+ {\def\@LN@maybe@moduloresume{%
+ \global\let\@LN@maybe@normalLineNumber
+ \@LN@normalLineNumber}%
+ \@LN@modulolinenos}%
+ {\let\@LN@maybe@moduloresume\relax \@LN@modulolinenos}%
+}
+
+\global\let\@LN@maybe@normalLineNumber\relax
+\let\@LN@maybe@moduloresume\relax
+\gdef\@LN@normalLineNumber{%
+ \ifnum\c@linenumber=\c@firstlinenumber \else
+ \ifnum\c@linenumber>\@ne
+ \def\LineNumber{\thelinenumber}%
+ \fi
+ \fi
+%%
+% ~\def~ instead of ~\let~ enables taking account of a
+% redefinition of ~\thelinenumber~ in a present numbering
+% environment (e.g.).
+%%
+ \global\let\@LN@maybe@normalLineNumber\relax}
+
+% Instead of changing ~\LineNumber~ directly by
+% ~LN@moduloresume~, these tricks enable ~\modulolinenumbers*~
+% to act as locally as I can make it. I don't know how to
+% avoid that the output routine switches back to the normal
+% modulo behaviour by a global change. (An ~\aftergroup~ may
+% fail in admittedly improbable cases.)
+
+\newcommand*\@LN@modulolinenos[1][\z@]{%
+%%
+% The definition of this macro is that of the former
+% ~\modulolinenumbers~. (/New v4.31)
+%%
+ \let\LineNumber\themodulolinenumber
+ \ifnum#1>\@ne
+ \chardef % v4.22, note below
+ \c@linenumbermodulo#1\relax
+ \else\ifnum#1=\@ne
+% \begin{old}\begin{verbatim}
+% % \def\LineNumber{\thelinenumber}%
+% \end{verbatim}
+% \end{old}
+% (New v4.00) I am putting something here to enable
+% ~\firstlinenumber~ with $~\c@linenumbermodulo~=1$.
+% With ~lnopatch.sty~, a trick was offered for this purpose.
+% It is now obsolete.
+%
+ \def\LineNumber{\@LN@ifgreat\thelinenumber}%
+%%
+% (/New v4.00)
+%%
+ \fi\fi
+ }
+
+% (New v4.00) The default of ~\@LN@ifgreat~ is
+
+\let\@LN@ifgreat\relax
+
+% The previous changes as soon as ~\firstlinenumber~ is used:
+
+\newcommand*\firstlinenumber[1]{%
+ \chardef\c@firstlinenumber#1\relax
+%%
+% No counter, little values allowed only---OK?---(UL)
+% The change is local---OK? The good thing is that
+% ~\global\firstlinenumber{~<number>~}~ works. Moreover,
+% ~\modulolinenumbers~ acts locally as well. (/UL)
+%
+% (New v4.31)
+%%
+ \let\@LN@ifgreat\@LN@ifgreat@critical}
+
+\def\@LN@ifgreat@critical{%
+ \ifnum\c@linenumber<\c@firstlinenumber
+ \expandafter \@gobble
+ \fi}%
+
+% (/New v4.31)
+%
+% The default
+% value of ~\c@firstlinenumber~ %% v4.31
+% is 0. This is best for what one would expect from modulo
+% printing.
+
+\let\c@firstlinenumber=\z@
+
+%
+% For usage and effects of ~\modulolinenumbers~ and %% v4.31
+% ~\firstlinenumbers~, please consult section_\ref{s:UserCmds}.
+% Two details on ~\firstlinenumbers~ here:
+% (i)_~\firstlinenumber~ acts on a paragraph if and only if
+% (a)_the paragraph is broken into lines ``in line-numbering
+% mode'' (after ~\linenumbers~, e.g.);
+% (b)_it is the last occurrence of a ~\firstlinenumbers~
+% before or in the paragraph.
+% (The practical applications of this that I can imagine
+% don't seem appealing to me.)
+% Cf._the explanation above of how ~\modulolinenumbers~ and
+% ~\firstlinenumbers~ interact---for this and for (ii),
+% which is concerned with possible arguments for
+% ~\firstlinenumbers~.
+%
+% Note that the line numbers of the present section
+% demonstrate the two devices. (/New v4.00)
+
+%%\setcounter{linenumbermodulo}{5}
+\chardef\c@linenumbermodulo=5 % v4.2; ugly?
+\modulolinenumbers[1]
+
+% (New v4.22) The new implementation through ~\chardef~
+% decreases the functionality and raises certain compatibility
+% problems. I face this without fear. The maximum modulo value
+% is now ~255~. I expect that this suffices for usual applications.
+% However, some users have ``abused'' ~lineno.sty~ to get
+% ~ednotes.sty~ features without line numbers, so have set the
+% modulo to a value beyond the total number of lines in their
+% edition. This ought to be replaced by
+% ~\let\makeLineNumber\relax~. (/New v4.22)
+%
+% \section{%
+% Package options
+% \unskip}\label{s:Opts}
+%
+% (New v4.1)
+% The last heading formerly was the heading of what is now
+% subsection_\ref{ss:v3opts}. The options declared there were
+% said to execute user commands only. This was wrong already
+% concerning ~displaymath~ and ~hyperref~. At least, however,
+% these options were no or almost no occasion to skip definitions
+% or allocations. This is different with the options that we now
+% insert.
+%
+%% (New v4.2) v4.00 moved the ``options'' below the
+%% ``extensions''. This was bad with ~\do@mlineno~ in
+%% subsection_\ref{ss:v3opts} which is to control
+%% subsection_\ref{ss:display}---undone here. (/New v4.2)
+%
+% \subsection{%
+% Extended referencing to line numbers. (v4.2)
+% \unskip}
+% This subsection explains and declares package option ~addpageno~. %% v4.31
+%
+% If a line to whose number you refer by ~\ref~ is not on the
+% present page, it may be useful to add the number of the page
+% on which the line occurs---and perhaps it should not be added
+% otherwise. In general, you could use the Standard \LaTeX\
+% package varioref for this. However, the latter usually
+% produces verbose output like `on the preceding page'---
+% unless costumized---, while in critical editions, e.g., one
+% may prefer just adding the page number and some mark on the
+% left of the line number, irrespectively of how far the page is
+% apart etc. To support this, package option ~addpageno~
+% provides a command ~\vpagelineref~ to be used in place of
+% ~\ref~. This produces, e.g., `34.15' when referring to line_15
+% on page_34 while the present page is not 34. You can customize
+% the outcome, see the package file ~vplref.sty~ where the code
+% and further details are. You may conceive of
+% ~\vpagelineref~ as a certain customization of varioref's
+% ~\vref~.
+%
+% This implies that option ~addpageno~ requires the files
+% ~vplref.sty~ and ~varioref.sty~. ~addpageno~ automatically
+% loads both of them. Yet you can also load ~varioref.sty~
+% on your own to use its package options.
+%
+% Of course, you might better introduce a shorter command name
+% for ~\vpagelineref~ for your work, while we cannot predict
+% here what shorthand will fit your work. E.g.,
+% ~\newcommand{\lref}{\vpagelineref}~.
+%
+% If you really want to add the page number in \emph{any} case,
+% use, e.g., some ~\myref~ instead of ~\ref~, after
+% \[~newcommand*{\myref}{\pageref{#1}.\ref{#1}}~\]
+% or what you like. You don't need the ~addpageno~ option in
+% this case.
+%
+% ~addpageno~ is due to a suggestion by Sergei Mariev.
+
+\DeclareOption{addpageno}{%
+ \AtEndOfPackage{\RequirePackage{vplref}[2005/04/25]}}
+
+% \subsection{%
+% \scs{linelabel} in math mode
+% \unskip}\label{ss:MathRef}
+%
+% We have made some first steps towards allowing ~\linelabel~ in
+% math mode. Because our code for this is presently experimental,
+% we leave it to the user to decide for the experiment by calling
+% option ~mathrefs~. We are in a hurry now and thus leave the
+% code, explanations, and discussion in the separate package
+% ~ednmath0.sty~. Maybe we later find the time to improve the
+% code and move the relevant content of ~ednmath0.sty~ to here.
+% The optimal situation would be to define ~\linelabel~ from
+% the start so it works in math mode, omitting the ~mathrefs~
+% option.
+%
+% Actually, this package even provides adjustments for analogously
+% allowing ~ednotes.sty~ commands in math mode. Loading the package
+% is postponed to ~\AtBeginDocument~ when we know whether these
+% adjustments are needed.
+
+\DeclareOption{mathrefs}{\AtBeginDocument
+ {\RequirePackage{ednmath0}[2004/08/20]}}
+
+%
+% \subsection{%
+% Arrays, tabular environments (Revised v4.11)
+% \unskip}\label{ss:Tab}
+%
+% This subsection explains and declares package options %% v4.31
+% ~edtable~, ~longtable~, and ~nolongtablepatch~.
+%
+% The standard \LaTeX\ tabular environments come as single
+% boxes, so the ~lineno.sty~ versions before v4.00 treated them as
+% (parts of) single lines, printing (at most) one line number
+% beside each and stepping the line number counter once only.
+% Moreover, ~\linelabel~s got lost. Of course, tables are
+% usually so high that you will want to treat each row like a
+% line. (Christian Tapp even desires that the lines of table
+% entries belonging to a single row are treated like ordinary
+% lines.) Footnotes get lost in such environments as well, which
+% was bad for ~ednotes.sty~.
+%
+% We provide adjustments to count lines, print their numbers
+% etc.\ as desired at least for \emph{some} \LaTeX\ tabular
+% environments. (Like with other details, ``some'' is to some
+% extent explained in ~edtable.sty~.) We do this similarly as
+% with option ~mathrefs~ before. We leave code
+% and explanations in the separate package ~edtable.sty~.
+% (For wizards: this package provides adjustments for
+% ~ednotes.sty~ as well. However, in the present case we don't try
+% to avoid them unless ~ednotes.sty~ is loaded.)
+% Package option ~edtable~
+% defines---by loading ~edtable.sty~---an environment ~{edtable}~
+% which is able to change some \LaTeX\ tabular environments
+% with the desired effects. (v4.11: ~edtable.sty~ v1.3 counts
+% \LaTeX's ~{array}~ [etc.\@] as a ``tabular environment'' as
+% well.)
+%
+% The ~{edtable}~ environment doesn't help with ~longtable.sty~,
+% however. To make up for this, ~{longtable}~ is adjusted in a
+% different way---and this happens only when another ~lineno.sty~
+% option ~longtable~ is called. In this case, option ~edtable~
+% needn't be called explicitly: option ~longtable~ works as if
+% ~edtable~ had been called.
+%
+% Now, we are convinced that vertical spacing around
+% ~{longtable}~ works wrongly---see \LaTeX\ bugs database
+% tools/3180 and 3485, or see explanations in the package
+% ~ltabptch.sty~ (which is to be obtained from CTAN folder
+% \path{macros/latex/ltabptch}). Our conviction is so strong
+% that the ~longtable~ option loads---after ~longtable.sty~---the
+% patch package ~ltabptch.sty~. If the user doesn't want this
+% (maybe preferring her own arrangement with the vertical
+% spacing), she can forbid it by calling ~nolongtablepatch~.
+%
+% The following code just collects some choices, which are
+% then executed in section_\ref{ss:ExOpt}. We use an ~\if...~
+% without ~\newif~ since ~\if...true~ and ~\if...false~
+% would occur at most two times and only within the present
+% package. (~\AtEndOfClass{\RequirePackage{edtable}}~
+% could be used instead, I just overlooked this. Now I don't
+% change it because it allows to change the version requirement
+% at one place only.)
+
+\let\if@LN@edtable\iffalse
+
+\DeclareOption{edtable}{\let\if@LN@edtable\iftrue}
+
+\DeclareOption{longtable}{\let\if@LN@edtable\iftrue
+ \PassOptionsToPackage{longtable}{edtable}}
+
+\DeclareOption{nolongtablepatch}{%
+ \PassOptionsToPackage{nolongtablepatch}{edtable}}
+
+% (/New v4.1)
+%
+% \subsection{%
+% Switch among settings
+% \unskip}\label{ss:v3opts}
+%
+% There is a bunch of package options that execute %% v4.2
+%% There is a bunch of package options, all of them executing
+%% executing only user commands (see below). %% Cf. start of section.
+% user commands only.
+%
+% Options ~left~ (~right~) put the line numbers on the left
+% (right) margin. This works in all modes. ~left~ is the
+% default.
+
+\DeclareOption{left}{\leftlinenumbers*}
+
+\DeclareOption{right}{\rightlinenumbers*}
+
+% Option ~switch~ (~switch*~) puts the line numbers on the
+% outer (inner) margin of the text. This requires running
+% the pagewise mode, but we turn off the page offset
+% subtraction, getting sort of running numbers again. The
+% ~pagewise~ option may restore true pagewise mode later.
+
+\DeclareOption{switch}{\setpagewiselinenumbers
+ \switchlinenumbers
+ \runningpagewiselinenumbers}
+
+\DeclareOption{switch*}{\setpagewiselinenumbers
+ \switchlinenumbers*%
+ \runningpagewiselinenumbers}
+
+% In twocolumn mode, we can switch the line numbers to
+% the outer margin, and/or start with number 1 in each
+% column. Margin switching is covered by the ~switch~
+% options.
+
+\DeclareOption{columnwise}{\setpagewiselinenumbers
+ \columnwiselinenumberstrue
+ \realpagewiselinenumbers}
+
+% The options ~pagewise~ and ~running~ select the major
+% linenumber mechanism. ~running~ line numbers refer to a real
+% counter value, which can be reset for any paragraph,
+% even getting multiple paragraphs on one page starting
+% with line number one. ~pagewise~ line numbers get a
+% unique hidden number within the document, but with the
+% opportunity to establish the page on which they finally
+% come to rest. This allows the subtraction of the page
+% offset, getting the numbers starting with 1 on top of each
+% page, and margin switching in twoside formats becomes
+% possible. The default mode is ~running~.
+%
+% The order of declaration of the options is important here
+% ~pagewise~ must come after ~switch~, to overide running
+% pagewise mode. ~running~ comes last, to reset the running
+% line number mode, e.g, after selecting margin switch mode
+% for ~pagewise~ running. Once more, if you specify all
+% three of the options ~[switch,pagewise,running]~, the
+% result is almost nothing, but if you later say
+% ~\pagewiselinenumbers~, you get margin switching, with
+% real pagewise line numbers.
+%
+\DeclareOption{pagewise}{\setpagewiselinenumbers
+ \realpagewiselinenumbers}
+
+\DeclareOption{running}{\setrunninglinenumbers}
+
+% The option ~modulo~ causes only those linenumbers to be
+% printed which are multiples of five.
+
+\DeclareOption{modulo}{\modulolinenumbers\relax}
+
+% Option ~modulo*~ modifies ~modulo~ in working like
+% ~\modulolinenumbers*~---see section_\ref{s:UserCmds}.
+
+\DeclareOption{modulo*}{\modulolinenumbers*\relax}
+
+% The package option ~mathlines~ switches the behavior of
+% the ~{linenomath}~ environment with its star-form.
+% Without this option, the ~{linenomath}~ environment does
+% not number the lines of the display, while the star-form
+% does. With this option, its just the opposite.
+%
+%%% 1999-06-10: renamed ~displaymath~ to ~mathlines~.
+
+\DeclareOption{mathlines}{\linenumberdisplaymath}
+
+% ~displaymath~ now calls for wrappers of the standard
+% \LaTeX\ display math environment. This was previously
+% done by ~mlineno.sty~.
+%
+% (New v4.3) Option `displaymath' becomes default according
+% to Erik \mbox{Luijten}'s suggestion. I was finally convinced
+% of this as soon as I discovered how to avoid a spurious line
+% number above ~\begin{linenomath}~ (subsection_\ref{ss:DM}).
+% ~\endlinenomath~ provides ~\ignorespaces~, so what could go
+% wrong now?
+
+\DeclareOption{displaymath}{\PackageWarningNoLine{lineno}{%
+ Option [displaymath] is obsolete -- default now!}}
+%%
+%%\let\do@mlineno\relax
+%%\DeclareOption{displaymath}{\let\do@mlineno\@empty}
+% (/New v4.3)
+%
+% \subsection{%
+% Compatibility with \texttt{hyperref} %% own subsec. v4.3.
+% \unskip}
+% The ~hyperref~ package, via ~nameref~, requires three more
+% groups in the second argment of a ~\newlabel~. Well, why
+% shouldn't it get them? (New v3.07) The presence of the
+% ~nameref~ package is now detected automatically
+% ~\AtBeginDocument~. (/New v3.07) (Fixed in v3.09) We try
+% to be smart, and test ~\AtBeginDocument~ if the ~nameref~
+% package is loaded, but ~hyperref~ postpones the loading of
+% ~nameref~ too, so this is all in vain.
+%
+% (New v4.3) But we can also test at the first ~\linelabel~.
+% Regarding the error-message for misplaced ~\linelabel~ from v4.11:
+% previously, ~\linenumbers~ rendered ~\linelabel~ the genuine
+% version of ~\linelabel~ from the start on. This doesn't work
+% now, since ~\@LN@linelabel~ may change its meaning after the
+% first ~\linenumbers~ and before a next one (if there is some).
+% (/New v4.3)
+
+\DeclareOption{hyperref}{\PackageWarningNoLine{lineno}{%
+ Option [hyperref] is obsolete.
+ \MessageBreak The hyperref package is detected automatically.}}
+
+\AtBeginDocument{%
+ \@ifpackageloaded{nameref}{%
+%%
+% (New v4.3) ``Global'' is merely ``symbolic'' ~\AtBeginDoc...~.
+% If ~nameref~ is not detected here, the next ~\@LN@linelabel~
+% will do almost the same, then globally indeed.
+%%
+ \gdef\@LN@ExtraLabelItems{{}{}{}}%
+ }{%
+ \global\let\@LN@@linelabel\@LN@linelabel
+ \gdef\@LN@linelabel{%
+%%
+% ~\@ifpackageloaded~ is ``preamble only'', its---very
+% internal---preamble definition is replicated here:
+%%
+ \expandafter
+ \ifx\csname ver@nameref.sty\endcsname\relax \else
+ \gdef\@LN@ExtraLabelItems{{}{}{}}%
+ \fi
+%%
+% Now aim at the ``usual'' behaviour:
+%%
+ \global\let\@LN@linelabel\@LN@@linelabel
+ \global\let\@LN@@linelabel\relax
+ \@LN@linelabel
+ }%
+ }%
+}
+
+% (/New v4.3)
+%
+% (New v4.1)
+% \subsection{%
+% A note on calling so many options
+% \unskip}
+%
+% The number of package options may stimulate worrying about how to
+% \emph{enter} all the options that one would like to use---they may
+% not fit into one line. Fortunately, you can safely break code lines
+% after the commas separating the option names in the ~\usepackage~
+% command (no comment marks needed).
+%
+% \subsection{%
+% Execute options
+% \unskip}\label{ss:ExOpt}
+%
+% We stop declaring options and execute the ones that are
+% called by the user. (/New v4.1)
+
+\ProcessOptions
+
+% (New v4.1) Now we know whether ~edtable.sty~ is wanted
+% and (if it is) with which options it is to be called.
+
+\if@LN@edtable \RequirePackage{edtable}[2005/03/07] \fi
+
+% (/New v4.1)
+%
+% \section{%
+% Former package extensions
+% \label{s:Xt}\unskip}
+%
+% The extensions in this section were previously supplied
+% in separate ~.sty~ files.
+%
+% \subsection{%
+% $display math$
+% \unskip}\label{ss:display}
+%% (New v4.32)
+% (New v4.3) From now on, you no longer need to type
+% the ~{linenomath}~ environment with the ~\[~, ~{equation}~,
+% and ~{eqnarray}~ environments---and you no longer need to
+% use the former package option ~displaymath~ for this feature.
+% (/New v4.3)
+%% (/New v4.32)
+%
+% The standard \LaTeX\ display math environments are
+% wrapped in a ~{linenomath}~ environment.
+%
+% (New 3.05) The ~[fleqn]~ option of the standard
+% \LaTeX\ classes defines the display math
+% environments such that line numbers appear just
+% fine. Thus, we need not do any tricks when
+% ~[fleqn]~ is loaded, as indicated by presents of
+% the ~\mathindent~ register. (/New 3.05)
+%
+% (New 3.05a) for ~{eqnarray}~s we rather keep the
+% old trick. (/New 3.05a)
+%
+% (New 3.08) Wrap ~\[~ and ~\]~ into ~{linenomath}~,
+% instead of ~{displaymath}~. Also save the definition
+% of ~\equation~, instead of replicating the current
+% \LaTeX\ definition. (/New 3.08)
+
+%%\ifx\do@mlineno\@empty
+ \@ifundefined{mathindent}{
+
+%% \AtBeginDocument{%
+ \let\LN@displaymath\[%
+ \let\LN@enddisplaymath\]%
+ \renewcommand\[{\begin{linenomath}\LN@displaymath}%
+ \renewcommand\]{\LN@enddisplaymath\end{linenomath}}%
+%
+ \let\LN@equation\equation
+ \let\LN@endequation\endequation
+ \renewenvironment{equation}%
+ {\linenomath\LN@equation}%
+ {\LN@endequation\endlinenomath}%
+%% }
+
+ }{}% \@ifundefined{mathindent} -- 3rd arg v4.2, was \par!
+
+%%\AtBeginDocument{%
+ \let\LN@eqnarray\eqnarray
+ \let\LN@endeqnarray\endeqnarray
+ \renewenvironment{eqnarray}%
+ {\linenomath\LN@eqnarray}%
+ {\LN@endeqnarray\endlinenomath}%
+%%}
+
+%%\fi
+
+% (UL) Indeed. The \LaTeX\ macros are saved for
+% unnumbered mode, which is detected by ~\linenomath~.
+% (/UL)
+%
+% \subsection{%
+% Line numbers in internal vertical mode
+% \unskip}\label{ss:ILN}
+%
+% The command ~\internallinenumbers~ adds line numbers in
+% internal vertical mode, but with limitations: we assume
+% fixed baseline skip.
+%
+% (v4.22) v3.10 provided a global (~\global\advance~)
+% as well as a local version (star-form, using
+% ~\c@internallinenumber~). ~\resetlinenumbers~ acted
+% locally and was here used with the global version---save
+% stack danger, \TeX book p._301---in v4.00 I
+% disabled the global version therefore. Now I find that
+% it is better to keep a global version, and the now global
+% ~\resetlinenumbers~ is perfect for this. The global version
+% allows continuing the ``internal'' numbers in the ensuing
+% ``external'' text, and---unless reset by brackets
+% argument---continuing the above series of line numbers.
+% As with v3.10, the local version always starts with
+% line number one. A new ~\@LN@iglobal~ steps ~\global~ly
+% in the global version, otherwise it is ~\relax~.
+% (I also remove all my stupid discussions as of v4.00.
+% And I use ~\newcommand~.) (v4.22)
+
+\let\@LN@iglobal\global % v4.22
+
+\newcommand\internallinenumbers{\setrunninglinenumbers
+ \let\@@par\internallinenumberpar
+ \ifx\@par\@@@par\let\@par\internallinenumberpar\fi
+ \ifx\par\@@@par\let\par\internallinenumberpar\fi
+ \ifx\@par\linenumberpar\let\@par\internallinenumberpar\fi
+ \ifx\par\linenumberpar\let\par\internallinenumberpar\fi
+ \@ifnextchar[{\resetlinenumber}%]
+ {\@ifstar{\let\c@linenumber\c@internallinenumber
+ \let\@LN@iglobal\relax % v4.22
+ \c@linenumber\@ne}{}}%
+ }
+
+\let\endinternallinenumbers\endlinenumbers
+\@namedef{internallinenumbers*}{\internallinenumbers*}
+\expandafter\let\csname endinternallinenumbers*\endcsname\endlinenumbers
+
+\newcount\c@internallinenumber
+\newcount\c@internallinenumbers
+
+\newcommand\internallinenumberpar{%
+ \ifvmode\@@@par\else\ifinner\@@@par\else\@@@par
+ \begingroup
+ \c@internallinenumbers\prevgraf
+ \setbox\@tempboxa\hbox{\vbox{\makeinternalLinenumbers}}%
+ \dp\@tempboxa\prevdepth
+ \ht\@tempboxa\z@
+ \nobreak\vskip-\prevdepth
+ \nointerlineskip\box\@tempboxa
+ \endgroup
+ \fi\fi
+ }
+
+\newcommand\makeinternalLinenumbers{%
+ \ifnum\c@internallinenumbers>\z@ % v4.2
+ \hb@xt@\z@{\makeLineNumber}%
+ \@LN@iglobal % v4.22
+ \advance\c@linenumber\@ne
+ \advance\c@internallinenumbers\m@ne
+ \expandafter\makeinternalLinenumbers\fi
+ }
+ % TODO v4.4+: star: line numbers right!? cf. lnocapt.sty
+
+%
+% \subsection{%
+% Line number references with offset
+% \unskip}
+%
+% This extension defines macros to refer to line
+% numbers with an offset, e.g., to refer to a line
+% which cannot be labeled directly (display math).
+% This was formerly knows as ~rlineno.sty~.
+%
+% To refer to a pagewise line number with offset:
+% \begin{quote}
+% ~\linerefp[~<OFFSET>~]{~<LABEL>~}~
+% \end{quote}
+% To refer to a running line number with offset:
+% \begin{quote}
+% ~\linerefr[~<OFFSET>~]{~<LABEL>~}~
+% \end{quote}
+% To refer to a line number labeled in the same mode as currently
+% selected:
+% \begin{quote}
+% ~\lineref[~<OFFSET>~]{~<LABEL>~}~
+% \end{quote}
+
+\newcommand\lineref{%
+ \ifx\c@linenumber\c@runninglinenumber
+ \expandafter\linerefr
+ \else
+ \expandafter\linerefp
+ \fi
+}
+
+\newcommand*\linerefp[2][\z@]{{%
+ \let\@thelinenumber\thelinenumber
+ \edef\thelinenumber{\advance\c@linenumber#1\relax
+ \noexpand\@thelinenumber}%
+ \ref{#2}%
+}}
+
+% This goes deep into \LaTeX's internals.
+
+\newcommand*\linerefr[2][\z@]{{%
+ \def\@@linerefadd{\advance\c@linenumber#1}%
+ \expandafter\@setref\csname r@#2\endcsname
+ \@linerefadd{#2}%
+}}
+
+\newcommand*\@linerefadd[2]{\c@linenumber=#1\@@linerefadd\relax
+ \thelinenumber}
+
+%% TODO v4.4+: Insert `LN' in internal command names?
+%
+% \subsection{%
+% Numbered quotation environments
+% \unskip}
+%
+% The ~{numquote}~ and ~{numquotation}~
+% environments are like ~{quote}~ and
+% ~{quotation}~, except there will be line
+% numbers.
+%
+% An optional argument gives the number to count
+% from. A star ~*~ (inside or outside the closing
+% ~}~) prevent the reset of the line numbers.
+% Default is to count from one.
+%
+% (v4.22: A local version using ~\c@internallinenumber~
+% might be useful, see subsection_\ref{ss:ILN}.) %% TODO v4.4+
+
+\newcommand\quotelinenumbers
+ {\@ifstar\linenumbers{\@ifnextchar[\linenumbers{\linenumbers*}}}
+
+\newdimen\quotelinenumbersep
+\quotelinenumbersep=\linenumbersep
+\let\quotelinenumberfont\linenumberfont
+
+\newcommand\numquotelist
+ {\leftlinenumbers
+ \linenumbersep\quotelinenumbersep
+ \let\linenumberfont\quotelinenumberfont
+ \addtolength{\linenumbersep}{-\@totalleftmargin}%
+ \quotelinenumbers
+ }
+
+\newenvironment{numquote} {\quote\numquotelist}{\endquote}
+\newenvironment{numquotation} {\quotation\numquotelist}{\endquotation}
+\newenvironment{numquote*} {\quote\numquotelist*}{\endquote}
+\newenvironment{numquotation*}{\quotation\numquotelist*}{\endquotation}
+
+%
+% \subsection{%
+% Frame around a paragraph
+% \unskip}
+%
+% The ~{bframe}~ environment draws a frame around
+% some text, across page breaks, if necessary.
+%
+% This works only for plain text paragraphs,
+% without special height lines. All lines must be
+% ~\baselineskip~ apart, no display math.
+
+\newenvironment{bframe}
+ {\par
+ \@tempdima\textwidth
+ \advance\@tempdima 2\bframesep
+ \setbox\bframebox\hb@xt@\textwidth{%
+ \hskip-\bframesep
+ \vrule\@width\bframerule\@height\baselineskip\@depth\bframesep
+ \advance\@tempdima-2\bframerule
+ \hskip\@tempdima
+ \vrule\@width\bframerule\@height\baselineskip\@depth\bframesep
+ \hskip-\bframesep
+ }%
+ \hbox{\hskip-\bframesep
+ \vrule\@width\@tempdima\@height\bframerule\@depth\z@}%
+ \nointerlineskip
+ \copy\bframebox
+ \nobreak
+ \kern-\baselineskip
+ \runninglinenumbers
+ \def\makeLineNumber{\copy\bframebox\hss}%
+ }
+ {\par
+ \kern-\prevdepth
+ \kern\bframesep
+ \nointerlineskip
+ \@tempdima\textwidth
+ \advance\@tempdima 2\bframesep
+ \hbox{\hskip-\bframesep
+ \vrule\@width\@tempdima\@height\bframerule\@depth\z@}%
+ }
+
+\newdimen\bframerule
+\bframerule=\fboxrule
+
+\newdimen\bframesep
+\bframesep=\fboxsep
+
+\newbox\bframebox
+
+%
+%
+% \section{%
+% Move \scs{vadjust} items (New v4.00)
+% \unskip}\label{s:MVadj}
+%
+% This section completes reviving ~\pagebreak~, ~\nopagebreak~,
+% ~\vspace~, and the star and optional form of ~\\~. This was
+% started in section_\ref{ss:output} and resumed in
+% section_\ref{ss:MLN} and subsection_\ref{ss:calls}.
+% The problem was explained in section_\ref{ss:output}:
+% ~\vadjust~ items come out at a bad position, and the
+% \LaTeX\ commands named before work with ~\vadjust~ indeed.
+% Our solution was sketched there as well.
+%
+% According to the caveat in subsection_\ref{ss:OnOff} concerning
+% ~\ifLineNumbers~, the \LaTeX\ commands enumerated may go
+% wrong if you switch line numbering inside or at the end of
+% a paragraph.
+%% %% TODO v4.4+
+%
+% \subsection{%
+% Redefining \scs{vadjust}
+% \unskip}\label{ss:PVadj}
+%
+% ~\vadjust~ will temporarily be changed into the following
+% command.
+
+\def\PostponeVadjust#1{%
+ \global\let\vadjust\@LN@@vadjust
+%%
+% This undoes a ~\global\let\vadjust\PostponeVadjust~ which will
+% start each of the refined \LaTeX\ commands. The ~\global~s
+% are most probably superfluous. They might be useful should one
+% ~\vadjust~ appear in a group starting after the change of
+% ~\vadjust~ into ~\PostponeVadjust~.
+% (UL) Even the undoing may be superfluous, cf._discussion
+% in section_\ref{ss:ReDef} below. (UL)
+%%
+ \vadjust{\penalty-\@Mppvacodepen}%
+ \g@addto@macro\@LN@vadjustlist{#1\@lt}%
+}
+\let\@LN@@vadjust\vadjust
+\global\let\@LN@vadjustlist\@empty
+\global\let\@LN@do@vadjusts\relax
+
+% These ~\global~s are just to remind that
+% all the changes of the strings after ~\let~ should be
+% ~\global~ (\TeX book p._301). ~\@LN@vadjustlist~ collects
+% the ~\vadjust~ items of a paragraph. ~\PassVadjustList~
+% tears one ~\vadjust~ item for the current line out of
+% ~\@LN@vadjustlist~ and puts it into ~\@LN@do@vadjusts~.
+% The latter is encountered each line in ~\MakeLineNo~
+% (section_\ref{ss:MLN}), while those \LaTeX\ ~\vadjust~
+% commands will come rather rarely. So I decided that
+% ~\@LN@do@vadjust~ is ~\relax~ until a ~\vadjust~ item
+% is waiting. In the latter case, ~\@LN@do@vadjusts~
+% is turned into a list macro which resets itself to
+% ~\relax~ when the other contents have been placed in
+% the vertical list.---~\PassVadjustList~ is invoked by
+% the output routine (section_\ref{ss:output}), so the
+% ~\box255~ must be put back.
+
+\def\PassVadjustList{%
+ \unvbox\@cclv
+ \expandafter \@LN@xnext \@LN@vadjustlist \@@
+ \@tempa \@LN@vadjustlist
+ \ifx\@LN@do@vadjusts\relax
+ \gdef\@LN@do@vadjusts{\global\let\@LN@do@vadjusts\relax}%
+ \fi
+ \expandafter \g@addto@macro \expandafter \@LN@do@vadjusts
+ \expandafter {\@tempa}%
+}
+
+%
+% \subsection{%
+% Redefining the \LaTeX\ commands
+% \unskip}\label{ss:ReDef}
+%
+% Now we change ~\pagebreak~ etc.\
+% so that they use ~\PostponeVadjust~ in place of ~\vadjust~.
+% We try to do this as independently as possible of the
+% implementation of the \LaTeX\ commands to be redefined.
+% Therefore, we don't just copy macro definition code from any
+% single implementation (say, latest \LaTeX) and insert our
+% changes, but attach a conditional
+% ~\global\let\vadjust\PostponeVadjust~
+% to their left ends in a way which should work rather
+% independantly of their actual code.
+% However, ~\vadjust~ should be the primitive again after
+% execution of the command. So the ~\global\let...~ may be used
+% only if it's guaranteed that a ~\vadjust~ is near.---(UL)
+% Sure? In line numbering mode, probably each ~\vadjust~
+% coming from a \LaTeX\ command should be ~\PostponeVadjust~.
+% ~\marginpar~s and floats seem to be the only cases which
+% are not explicitly dealt with in the present section.
+% This would be a way to avoid ~\@LN@nobreaktrue~!
+% Of course, the ~\vadjust~s that the present package uses
+% then must be replaced by ~\@LN@@vadjust~.---Maybe
+% next time. (/UL)
+%% %% TODO v4.4+
+%
+% The next command and something else will be added to the
+% \LaTeX\ commands we are concerned with here.
+
+\DeclareRobustCommand\@LN@changevadjust{%
+ \ifvmode\else\ifinner\else
+ \global\let\vadjust\PostponeVadjust
+ \fi\fi
+}
+
+% (UL) What about math mode? Math display? Warn? (/UL)
+%% %% TODO v4.4+
+%
+% ~\@tempa~ will now become a two place macro which adds first
+% argument (single token), enclosed by ~\ifLineNumbers~\,\dots
+% ~\fi~ to the left of second argument. As long as we need it,
+% we can't use the star form of ~\DeclareRobustCommand~ or
+% the like, because AMS-\LaTeX\ uses ~\@tempa~ for ~\@ifstar~.
+% (New v4.41) And for the same reason, that ~\CheckCommand*~
+% had to be raised! (/New v4.41)
+
+\CheckCommand*\@parboxrestore{\@arrayparboxrestore\let\\\@normalcr}
+
+\def\@tempa#1#2{%
+ \expandafter \def \expandafter#2\expandafter{\expandafter
+ \ifLineNumbers\expandafter#1\expandafter\fi#2}%
+}
+
+% (UL) This ~\ifLineNumber~ can be fooled by
+% ~\linenumbers~ ahead etc. It might be better to place
+% a signal penalty in any case and let the output routine
+% decide what to do.
+%%
+%% And when this has been done, remove warnings about this.
+% (/UL)
+%
+% We use the occasion to switch off linenumbers where they
+% don't work anyway and where we don't want them,
+% especially in footnotes:
+
+\@tempa\nolinenumbers\@arrayparboxrestore
+
+% We hope this suffices $\dots$ let's check one thing
+% at least: [(New v4.41) see ~\CheckCommand~ above (/New v4.41)]
+%
+% Now for the main theme of the section.
+% The next lines assume that ~\vspace~, ~\pagebreak~, and
+% ~\nopagebreak~ use ~\vadjust~ whenever they occur outside
+% vertical mode; moreover, that they don't directly read
+% an argument. Indeed ~\pagebreak~ and ~\nopagebreak~ first
+% call something which tests for a left bracket ahead,
+% while ~\vspace~ first tests for a star.
+
+\@tempa\@LN@changevadjust\vspace
+\@tempa\@LN@changevadjust\pagebreak
+\@tempa\@LN@changevadjust\nopagebreak
+
+% ~\\~, however, uses ~\vadjust~ only in star or optional form.
+% We relax independency of implementation in assuming
+% that ~\@normalcr~ is the fragile version of ~\\~
+% (and we use ~\@ifstar~!).
+%%
+%% \@ifstar reimplemented 1995/10/16, but seems to be much older.
+%% TODO v4.4+:
+%% \def\@LN@cr{%
+%% \@ifnextchar*{\@LN@changevadjust\@normalcr}%
+%% {\@ifnextchar[{\@LN@changevadjust\@normalcr}\@normalcr}%
+%% }
+%% ---same number of tokens, expansion step less.
+%%
+% (Using a copy of ~\\~ would be safer, but an ugly repetition
+% of ~\protect~.)
+%% %% TODO v4.4+
+
+\DeclareRobustCommand\\{%
+ \ifLineNumbers
+ \expandafter \@LN@cr
+ \else
+ \expandafter \@normalcr
+ \fi
+}
+\def\@LN@cr{%
+ \@ifstar{\@LN@changevadjust\@normalcr*}%
+ {\@ifnextchar[{\@LN@changevadjust\@normalcr}\@normalcr}%
+}
+
+% Moreover we hope that ~\newline~ never leads to a ~\vadjust~,
+% although names of some commands invoked by ~\\~ contain
+% ~newline~. At last, this seems to have been OK since 1989 or
+% even earlier.
+%
+% \modulolinenumbers[1]
+% \firstlinenumber{0}
+% Let's have a few tests.\vspace*{.5\baselineskip}
+% Testing ~\pagebreak~ and ~\nopagebreak~ would be too expensive
+% here, but---oops!---we have just experienced a successful
+% ~\vspace*{.5\baselineskip}~. A
+% ~\\*[.5\baselineskip]~\\*[.5\baselineskip] may look even more
+% drastical, but this time we are happy about it. Note that the
+% line numbers have moved with the lines. Without our changes,
+% one line number\vadjust{\kern.5\baselineskip} would have
+% ``anticipated'' the move of the next line, just as you can
+% observe it now.
+% (/New v4.00)
+%
+% \switchlinenumbers
+%
+% \subsection{%
+% Reminder on obsoleteness
+% \unskip}
+%
+% (New v4.1) We have completed inclusion of the earlier
+% extension packages ~linenox0.sty~, ~linenox1.sty~, and
+% ~lnopatch.sty~. If one of them is loaded, though,
+% we produce an error message before something weird happens.
+% We avoid ~\newif~ because the switchings occur so rarely.
+
+\AtBeginDocument{%
+ \let\if@LN@obsolete\iffalse
+ \@ifpackageloaded{linenox0}{\let\if@LN@obsolete\iftrue}\relax
+ \@ifpackageloaded{linenox1}{\let\if@LN@obsolete\iftrue}\relax
+ \@ifpackageloaded{lnopatch}{\let\if@LN@obsolete\iftrue}\relax
+ \if@LN@obsolete
+ \PackageError{lineno}{Obsolete extension package(s)}{%
+ With lineno.sty version 4.00 or later,\MessageBreak
+ linenox0/linenox1/lnopatch.sty must no longer be loaded.}%
+ \fi
+}
+
+%
+% \modulolinenumbers[1]
+% \section{%
+% The final touch
+% \unskip}
+%
+% There is one deadcycle for each line number.
+
+\advance\maxdeadcycles 100
+
+\endinput
+
+%
+% \section{%
+% The user commands
+% \unskip}\label{s:UserCmds}
+%
+% The user commands to turn on and off line numbering
+% are
+% \begin{description}\item
+% [|\linenumbers] \ \par
+% Turn on line numbering in the current mode.
+%
+% \item
+% [|\linenumbers*] \ \par$\qquad$
+% and reset the line number to 1.
+% \def\NL{<number>]}\item
+%% %% Boldface italic occurs here, which is evil. (UL)
+% [|\linenumbers[\NL] \ \par$\qquad$
+% and start with <number>.
+% \item
+% [|\nolinenumbers] \ \par
+% Turn off line numbering.
+% \item
+% [|\runninglinenumbers*[\NL] \ \par
+% Turn on ~running~ line numbers, with the same optional
+% arguments as ~\linenumbers~. The numbers are running
+% through the text over pagebreaks. When you turn
+% numbering off and on again, the numbers will continue,
+% except, of cause, if you ask to reset or preset the
+% counter.
+% \item
+% [|\pagewiselinenumbers] \ \par
+% Turn on ~pagewise~ line numbers. The lines on each
+% page are numbered beginning with one at the first
+% ~pagewise~ numbered line.
+% \item
+% [|\resetlinenumber[\NL] \ \par
+% Reset ~[~Set~]~ the line number to 1
+% ~[~<number>~]~.
+% \item
+% [|\setrunninglinenumbers] \ \par
+% Switch to ~running~ line number mode. Do \emph{not}
+% turn it on or off.
+% \item
+% [|\setpagewiselinenumbers] \ \par
+% Switch to ~pagewise~ line number mode. Do \emph{not}
+% turn it on or off.
+% \item
+% [|\switchlinenumbers*] \ \par
+% Causes margin switching in pagewise modes. With the
+% star, put the line numbers on the inner margin.
+% \item
+% [|\leftlinenumbers*] \ \par
+% \item
+% [|\rightlinenumbers*] \ \par
+% Set the line numbers in the left/right margin. With the
+% star this works for both modes of operation, without
+% the star only for the currently selected mode.
+% \item
+% [|\runningpagewiselinenumbers] \ \par
+% When using the pagewise line number mode, do not
+% subtract the page offset. This results in running
+% line numbers again, but with the possibility to switch
+% margins. Be careful when doing line number
+% referencing, this mode status must be the same while
+% setting the paragraph and during references.
+% \item
+% [|\realpagewiselinenumbers] \ \par
+% Reverses the effect of ~\runningpagewiselinenumbers~.
+% \item
+% [|\modulolinenumbers[\NL] \ \par
+% Give a number only to lines which are multiples of
+% ~[~<number>~]~. If <number> is not specified, the
+% current value in the counter ~linenumbermodulo~ is
+% retained. <number>=1 turns this off without changing
+% ~linenumbermodulo~. The counter is initialized to 5.
+%%
+%% %% TODO v4.4+: `counter', he says. Cf._above.
+%%
+%% (New v4.31)
+% \item
+% [|\modulolinenumbers*[\NL] \ \par
+% Like ~\modulolinenumbers~, the only difference being
+% that the first line number after a ~\linenumbers~
+% (or ~\runninglinenumbers~, ~\pagewiselinenumbers~,
+% ~\quotelinenumbers~) is printed regardless of the
+% modulo---yet `1' is printed only after (or \dots)
+% ~\firstlinenumber{1}~.
+% This also applies to the first line of a
+% ~{linenumbers}~ or respective environment.
+% See subsection_\ref{ss:Mod} for another explanation.
+% The behaviour may be unsatisfactory with pagewise
+% line-numbering.
+%% (/New v4.31)
+%% (New v4.00)
+% \item
+% [|\firstlinenumber] \ \par
+% ~\firstlinenumber{~<filino>~}~ brings about that
+% (after it) line numbers less than <filino> do
+% \emph{not} appear in the margin. Moreover, with
+% ~\modulolinenumbers[~<number>~]~, just the line
+% numbers which are <filino> plus a multiple of
+% <number> are printed.---If you had
+% ~\firstlinenumber{~<pos>~}~ with some $\mbox{<pos>}>0$
+% and want to switch to printing multiples of, e.g.,
+% 4, you best do ~\modulolinenumbers[4]~ and
+% ~\firstlinenumber{0}~. (See subsection_\ref{ss:Mod}
+% for technical details.)
+%% (/New v4.00)
+% \item
+% [|\linenumberdisplaymath] \ \par
+% Number the lines of a display math in a ~{linenomath}~
+% environment, but do not in a ~{linenomath*}~
+% environment. This is used by the package option
+% ~[mathlines]~.
+% \item
+% [|\nolinenumberdisplaymath] \ \par
+% Do not Number the lines of a display math in a
+% ~{linenomath}~ environment, but do in a
+% ~{linenomath*}~ environment. This is the default.
+% \item
+% [|\linelabel] \ \par
+% Set a ~\linelabel{~<foo>~}~ to the line number where
+% this commands is in. Refer to it with the \LaTeX\
+% referencing commands ~\ref{~<foo>~}~ and
+% ~\pageref{~<foo>~}~.
+% \end{description}
+% The commands can be used globally, locally within groups
+% or as environments. It is important to know that they
+%%
+%% %% TODO: \linelabel? others?
+%%
+% take action only when the ~\par~ is executed. The
+%%
+%% %% TODO: sure? ~\modulo...~, e.g.? well, in a sense ...
+%%
+% ~\end{~<mode>~linenumbers}~ commands provide a ~\par~.
+% Examples:
+% \begin{verse}
+% ~{\linenumbers~ <text> ~\par}~ \\
+% \ \\
+% ~\begin{linenumbers}~ \\
+% <text> \\
+% ~\end{linenumbers}~ \\
+% \ \\
+% <paragraph> ~{\linenumbers\par}~ \\
+% \ \\
+% ~\linenumbers~ \\
+% <text> ~\par~ \\
+% ~\nolinenumbers~ \\
+% \ \\
+% ~\linenumbers~ \\
+% <paragraph> ~{\nolinenumbers\par}~ \\
+% \end{verse}
+% (New v4.00)
+% However, the examples containing <paragraph> show what you
+% should \emph{not} do, at least if you use ~\pagebreak~,
+% ~\nopagebreak~, ~\vspace~, ~\\*~ or
+% ~\\[~<space>~]~---cf._section_\ref{s:MVadj}.
+%
+% The same care should be applied to the ``wizard'' devices
+% ~\ifLineNumbers~ (subsection_\ref{ss:OnOff}) and
+% ~\PostponeVadjust~ (section_\ref{ss:PVadj}).
+% (/New v4.00)
+%
+% (New v4.11) Oh, and the commands and environments of
+% section_{s:Xt} are missing. Sorry, I am in a hurry now.
+% May be next time.% %% TODO v4.4+
+% ---And the environments ~{linenomath}~ and ~{linenomath*}~should
+% get an own paragraph. In short, each math display, equation,
+% or ~{eqnarray}~ should be ``wrapped'' in one of ~{linenomath}~
+% and ~{linenomath*}~.
+%
+% \subsection{%
+% Customization hooks
+% \unskip}
+%
+% There are several hooks to customize the appearance of the
+% line numbers, and some low level hooks for special
+% effects.
+% \begin{description}\item
+% [|\thelinenumber] \ \par
+% This macro should give the representation of the line
+% number in the \LaTeX-counter ~linenumber~. The
+% default is provided by \LaTeX: \par$\qquad$
+% ~\arabic{linenumber}~
+% \item
+% [|\makeLineNumberLeft] \ \par
+% This macro is used to attach a line number to the left
+% of the text page. This macro should fill an ~\hbox to 0pt~
+% which will be placed at the left margin of the
+% page, with the reference point aligned to the line to
+% which it should give a number. Please use the macro
+% ~\LineNumber~ to refer to the line number.
+%
+% The default definition is \par$\qquad$
+% ~\hss\linenumberfont\LineNumber\hskip\linenumbersep~
+% \item
+% [|\makeLineNumberRight] \ \par
+% Like ~\makeLineNumberLeft~, but for line numbers on
+% the right margin.
+%
+% The default definition is \par$\qquad$
+% ~\linenumberfont\hskip\linenumbersep\hskip\textwidth~ \par$\qquad$
+% ~\hbox to\linenumberwidth{\hss\LineNumber}\hss~
+% \item
+% [|\linenumberfont] \ \par
+% This macro is initialized to \par$\qquad$
+% ~\normalfont\tiny\sffamily~
+% \item
+% [|\linenumbersep] \ \par
+% This dimension register sets the separation of the
+% linenumber to the text. Default value is ~10pt~.
+% \item
+% [|\linenumberwidth] \ \par
+% This dimension register sets the width of the line
+% number box on the right margin. The distance of the
+% right edge of the text to the right edge of the line
+% number is ~\linenumbersep~ + ~\linenumberwidth~. The
+% default value is ~10pt~.
+% \item
+% [|\theLineNumber] (for wizards) \ \par
+% This macro is called for printing a ~\newlabel~ entry
+% to the aux-file. Its definition depends on the mode.
+% For running line numbers it's just ~\thelinenumber~,
+% while in pagewise mode, the page offset subtraction
+% is done in here.
+% \item
+% [|\makeLineNumber] (for wizards) \ \par
+% This macro produces the line numbers. The definition
+% depends on the mode. In the running line numbers
+% mode it just expands ~\makeLineNumberLeft~.
+% \item
+% [|\LineNumber] (for wizards) \ \par
+% This macro is called by ~\makeLineNumber~ to typeset
+% the line number. This hook is changed by the modulo
+% mechanism
+%% %%%.
+% and by ~\firstlinenumber~.
+%% %% New v4.00
+% \end{description}
+%%
+%% TODO: \stepLineNumber---another wizard command!?
+%% Not sure, may be retreated.
+% \end{document}%D
+------------------------------------------------------------------------------
+ %SSTOPP
+%% TODO v4.4+: Check for unwanted comment marks in new comments
+%% (resulting from manual aligning): search `New v4.2'
+%% and/or ` % '!
+%% TODO v4.4+: Check for missing comment marks where a paragraph
+%% should end/start. Also to prevent empty "code" lines.
+%% Especially, new comments at section ends must be
+%% followed by comment mark lines.
+%% And prevent ~\par~s from blank lines in definitions!
+%% See `visual space' above.
+%% For proper appearance in lineno.tex, note that a comment
+%% in a final code line changes behaviour.
+%% TODO v4.4+: Require README for redistribution?
+%% TODO v4.4+: Since discussions of code have increased so much, it
+%% would be appropriate not to give to this file
+%% extension `.sty' (e.g., `dty'!??). ?? Is quickly read though!
+%% A .sty extraction may be possible even if the present
+%% file is neither a .doc nor a .dtx. (!???)
+%% Use awk line below (etc.) for .doc at least; + .ins or so.
+%% ^ must not be caps! To escape awk.
+%% TODO v4.4+: Underfull lines!? (due to long code quotations)
+%% TODO v4.4+: Sometimes paragraph indents may be appropriate.
+%% TODO Swap first line (`\iffalse...') with corresponding below.
+ Or do *not* swap, maybe nawk is more reliable.
+%% TODO v4.4+: Ponder Stephan's mail from 2004/09/02.
+%% TODO v4.4+:
+%% use \@ET@makeLineNumber.
+%% plus almost all `(UL)'
+%% plus lots of bad boxes messages
+%% change v4.3 TODOs when postponed
+%% remove {old} environments.
+
+------------------------------------------------------------------------------
+
+# awk command lines for v4.00, mixed with former ones:
+
+echo "Don't bother about unknown 'iffalse'." # SHELL1
+nawk '/A[W]K/' lineno.sty | nawk -f - lineno.sty >lineno.tex; # SHELL1
+latex lineno; latex lineno; latex lineno; latex lineno; # SHELL1
+
+BEGIN{DOC=-1; # AWK DOC A W K
+ BEGINCODE = "\\begin{code}\\begin{verbatim}"; # AWK
+ ENDCODE = "\\end{verbatim}\n\\end{code}"; } # AWK
+ BEGINCODE = "% \\begin{macrocode}"; # DOC A W K
+ ENDCODE = "% \\end{macrocode}"; } # DOC A W K
+/^[ \t]*$/ { ECNT++; next; } # AWK DOC A W K
+/\\documentclass/{ sub("article","ltxdoc") } # DOC A W K
+/%D$/ { sub("^%* *",""); sub("%D$",""); # DOC A W K
+ print > "lineno.drv"; next } # DOC A W K
+/^%%/ { next; } # AWK DOC A W K
+/^%/ { if (!DOC) { print ENDCODE; } # AWK DOC A W K
+ DOC=1; ECNT=0; # AWK DOC A W K
+ sub("^% *",""); # AWK
+ sub("^% *","% "); # DOC A W K
+ print; next; } # AWK DOC A W K
+/%VERSION/ { sub("%VERSION",""); print; next; } # AWK
+/%SSTOPP/ { exit } # AWK
+DOC<0 { next } # AWK DOC A W K
+/^-+-$/ { if (!DOC) print ENDCODE; exit } # AWK DOC A W K
+{ if (DOC) { ECNT=DOC=0; print BEGINCODE; } # AWK DOC A W K
+ while (ECNT>0) { print " "; ECNT--; } # AWK DOC A W K
+ print $0; } # AWK DOC A W K
+
+# New v4.00, UL: know nothing about awk; found present solution
+# in hours of trial and error.
+
+% Earlier (should be inhibited by %SSTOPP above and otherwise):
+echo "expect errors for unknown commands 'iffalse' and 'fi'";# SHELL0 SHELL#1
+awk '/A[W]K/' lineno.sty | awk -f - lineno.sty >lineno.tex; # SHELL0
+latex lineno; latex lineno; latex lineno; latex lineno; # SHELL0
+nawk '/A[W]K/' lineno4.sty | nawk -f - lineno4.sty >lineno4.tex; # SHELL#1
+latex lineno4; latex lineno4; latex lineno4; latex lineno4; # SHELL#1
+
+awk '/DOC A [W] K/' lineno.sty | awk -f - lineno.sty >lineno.doc; # DOC SH
+
+BEGIN{DOC=-1; # A#WK DOC A W K
+ BEGINCODE = "\\begin{code}\\begin{verbatim}"; # A#WK
+ ENDCODE = "\\end{verbatim}\n\\end{code}"; } # A#WK
+ BEGINCODE = "% \\begin{macrocode}"; # DOC A W K
+ ENDCODE = "% \\end{macrocode}"; } # DOC A W K
+/^[ \t]*$/ { ECNT++; next; } # A#WK DOC A W K
+/\\documentclass/{ sub("article","ltxdoc") } # DOC A W K
+/%D$/ { sub("^%* *",""); sub("%D$",""); # DOC A W K
+ print > "lineno.drv"; next } # DOC A W K
+/^%%/ { next; } # A#WK DOC A W K
+/^%/ { if (!DOC) { print ENDCODE; } # A#WK DOC A W K
+ DOC=1; ECNT=0; # A#WK DOC A W K
+ sub("^% *",""); # A#WK
+ sub("^% *","% "); # DOC A W K
+ print; next; } # A#WK DOC A W K
+DOC<0 { next } # A#WK DOC A W K
+/^-+-$/ { if (!DOC) print ENDCODE; exit } # A#WK DOC A W K
+{ if (DOC) { ECNT=DOC=0; print BEGINCODE; } # A#WK DOC A W K
+ while (ECNT>0) { print " "; ECNT--; } # A#WK DOC A W K
+ print $0; } # A#WK DOC A W K
+
+
+------------------------------------------------------------------------------
+
+If you are looking here because of the two top lines of the file:
+
+A .tex documentation of this macro file can be obtained by
+
+ sh lineno.sty
+
+under UNIX.--You may find this hint little helpful. One
+reason may be that the awk versions to which you have access
+don't work suitably. Another reason may be that you don't have
+access to UNIX (in some sense). However, a .tex, .dvi, or .pdf
+version of such a documentation should be available from CTAN,
+in the same folder as the present file. When we typed this, that
+folder was /macros/latex/contrib/lineno. If this has changed in
+the meantime, a CTAN search should lead you to a folder
+containing such a documentation. Or you may get help from one of
+the e-mail addresses above.
+
+
