% \iffalse meta-comment % % Copyright (C) 2004 Scott Pakin % ---------------------------------------------------- % % This package may be distributed and/or modified under the % conditions of the LaTeX Project Public License, either version 1.2 % of this license or (at your option) any later version. % The latest version of this license is in % http://www.latex-project.org/lppl.txt % and version 1.2 or later is part of all distributions of LaTeX % version 1999/12/01 or later. % % \fi % \iffalse %% File: eqparbox.dtx Copyright (C) 2004 Scott Pakin % %\NeedsTeXFormat{LaTeX2e} %\ProvidesPackage{eqparbox} % [2004/08/02 v2.1 Create equal-widthed parboxes] % %<*driver> \documentclass{ltxdoc} \usepackage{eqparbox} \EnableCrossrefs \CodelineIndex \RecordChanges % Uncomment the following line if you don't want to include a % source-code listing. %\OnlyDescription % Give LaTeX some more leeway in placing floats % (suggested by Donald Arseneau ). \renewcommand{\topfraction}{0.85} \renewcommand{\bottomfraction}{0.7} \renewcommand{\textfraction}{0.15} \renewcommand{\floatpagefraction}{0.66} \renewcommand{\dbltopfraction}{0.66} \renewcommand{\dblfloatpagefraction}{0.66} \setcounter{topnumber}{9} \setcounter{bottomnumber}{9} \setcounter{totalnumber}{20} \setcounter{dbltopnumber}{9} % Because we put table captions *above* tables, we should add a % little extra space between the caption and the table. \setlength{\belowcaptionskip}{2ex} \begin{document} \DocInput{eqparbox.dtx} \end{document} % % \fi % % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % \CheckSum{169} % \GetFileInfo{eqparbox.sty} % % \title{The \textsf{eqparbox} package\thanks{This file % has version number \fileversion, last % revised \filedate.}} % \author{Scott Pakin \\ \textit{scott+eqp@pakin.org}} % \date{\filedate} % \maketitle % % \changes{v1.0}{2001/04/19}{Initial version} % \changes{v2.0}{2004/07/31}{Rewrote to use only two \meta{dimen}s total % and the rest macros (problem reported by Gilles P\'erez-Lambert and % Plamen Tanovski; solution suggested by David Kastrup and Donald % Arseneau)} % % \DoNotIndex{\@auxout,\@ifnextchar,\@ifundefined} % \DoNotIndex{\begin,\begingroup,\csname,\DeclareRobustCommand,\def} % \DoNotIndex{\else,\end,\endcsname,\endgroup,\expandafter,\fi,\gdef,\global} % \DoNotIndex{\hbox,\ifdim,\ifx,\immediate,\let} % \DoNotIndex{\newcommand,\newdimen,\newif,\newlength,\noexpand} % \DoNotIndex{\relax,\setbox,\space,\string,\the,\wd,\xdef,\z@} % % \begin{abstract} % The \textsf{eqparbox} package makes it easy to define a group of % \verb|\parbox|es whose members all have the same width, the natural % width of the widest member. A document can contain any number of % groups, and each group can contain any number of members. This % simple, equal-width mechanism can be used for a variety of alignment % purposes, as is evidenced by the examples in this document. % \end{abstract} % % \section{Motivation} % % Let's start with a little test. How would you typeset % Table~\ref{tbl:sales-data}, in which the numbers are right-justified % relative to each other but centered as a group within each column. % And second, how would you typeset the r\'esum\'e excerpt shown in % Figure~\ref{fig:resume-excerpt} while meeting the following % requirements: % % \begin{enumerate} % \item The header columns must be left-justified relative to each % other. % \item The headers columns should be evenly spaced across the page. % \item Page breaks should be allowed within the r\'esum\'e. % \end{enumerate} % % \begin{table}[tp] % \centering % \caption{Sample sales data} % \label{tbl:sales-data} % \begin{tabular}{@{}lccc@{}} \hline % & \multicolumn{3}{c}{Sales (in millions)} \\ \cline{2-4} % \multicolumn{1}{c}{\raisebox{1ex}[2ex]{Product}} & % October & November & December \\ \hline % % Widgets & \eqparbox{oct}{\raggedleft 55.2 } & % \eqparbox{nov}{\raggedleft\textbf{ 89.2}} & % \eqparbox{dec}{\raggedleft 57.9 } \\ % Doohickeys & \eqparbox{oct}{\raggedleft\textbf{ 65.0}} & % \eqparbox{nov}{\raggedleft 64.1 } & % \eqparbox{dec}{\raggedleft 9.3 } \\ % Thingamabobs & \eqparbox{oct}{\raggedleft 10.4 } & % \eqparbox{nov}{\raggedleft 8.0 } & % \eqparbox{dec}{\raggedleft\textbf{109.7}} \\ \hline % \end{tabular} % \end{table} % % \begin{figure} % \bigskip\noindent\rule{\linewidth}{1pt}\bigskip\par % \noindent% % \eqparbox{place}{\textbf{Widgets, Inc.}} \hfill % \eqparbox{title}{\textbf{Senior Widget Designer}} \hfill % \eqparbox{dates}{\textbf{1/95--present}} % % \begin{itemize} % \item Supervised the development of the new orange and blue widget lines. % \item Improved the design of various widgets, making them less sticky % and far less likely to explode. % \item Made widget management ten times more cost-effective. % \end{itemize} % % \noindent% % \eqparbox{place}{\textbf{Thingamabobs, Ltd.}} \hfill % \eqparbox{title}{\textbf{Lead Engineer}} \hfill % \eqparbox{dates}{\textbf{9/92--12/94}} % % \begin{itemize} % \item Found a way to make thingamabobs run on solar power. % \item Drafted a blueprint for a new doohickey-compatibility module for % all cool-mint thingamabobs. % \item Upgraded superthingamabob specification document from Microsoft % Word to \LaTeXe. % \end{itemize} % \noindent\rule{\linewidth}{1pt} % \caption{Excerpt from a sample r\'esum\'e} % \label{fig:resume-excerpt} % \end{figure} % % The two questions can be answered the same way: by putting various % blocks of text into equal-widthed boxes. if the data in % Table~\ref{tbl:sales-data} are put into equal-sized |\parbox|es, each % containing a |\raggedleft| for right-justification, the |\parbox|es % can then be centered to achieve the desired result. Similarly, if the % company names in Figure~\ref{fig:resume-excerpt} are both put in a % |\parbox| as wide as ``Thingamabobs, Ltd.,'' the job titles in a % |\parbox| as wide as ``Senior Widget Designer,'' and the dates in a % |\parbox| as wide as ``1/95--present,'' then they can be spaced evenly % by separating them with |\hfill|s. % % The problem is in choosing the width for each set of |\parbox|es. For % Table~\ref{tbl:sales-data}, this isn't too difficult, because digits % are the same width as each other in most fonts. Each |\parbox|, % therefore, need be only as wide as the largest sequence of digits % expected. Figure~\ref{fig:resume-excerpt} is more of a bother. The % user must typeset the r\'esum\'e once to see which entry in each % column is the widest and then assign lengths appropriately: % % \begin{verbatim} % \newlength{\placewidth} % \settowidth{\placewidth}{Thingamabobs, Ltd.} % Employment 2 % \newlength{\jobtitlewidth} % \settowidth{\jobtitlewidth}{Senior Widget Designer} % Employment 1 % \newlength{\dateswidth} % \settowidth{\dateswidth}{1/95--present} % Employment 1 % \end{verbatim} % % \noindent % Every time a piece of information changes, it must be changed in two % places: in the r\'esum\'e itself and in the |\settowidth| % command. When employment information is added or deleted, the % |\settowidth| commands must be modified to reflect the new % maximum-widthed entry in each column. If only there were a simpler % way to keep a set of |\parbox|es as wide as the widest entry in the % set\,\dots % % That simpler way is the \textsf{eqparbox} package. \textsf{eqparbox} % exports a macro, |\eqparbox|, which works just like |\parbox|, except % that instead of specifying the width of the box, one specifies the % group that the box belongs to. All boxes in the same group will be % typeset as wide as the widest member of the group. In that sense, an % |\eqparbox| behaves like a cell in an~|l|, |c|, or~|r| column in a % |tabular|; |\eqparbox|es in the same group are analogous to % cells in the same column. % % \section{Usage} % % \DescribeMacro{\eqparbox} % The primary macro in the \textsf{eqparbox} package is |\eqparbox|. % Usage is almost identical to that of |\parbox|: % % \begin{center} % |\eqparbox| \oarg{pos} \oarg{height} \oarg{inner-pos} % \marg{tag} \marg{text} % \end{center} % % \noindent % The only difference is that, where |\parbox| has its \meta{width} % argument, |\eqparbox| has \meta{tag}. (For a description of the % remaining arguments, look up |\parbox| in any \LaTeXe\ book or in % the \texttt{usrguide.tex} file that comes with \LaTeXe.) \meta{tag} % can be any valid identifier. All |\eqparbox|es with the same tag % will be typeset in a box wide enough to hold the widest of them. % Discounting \TeX's limitations, any number of tags can be used in the % same document, and any number of |\eqparbox|es can share a tag. % % The only catch is that \texttt{latex} will need to be run a second % time for the various box widths to stabilize. % % \bigskip % % \DescribeMacro{\eqboxwidth} % It is sometimes useful to take the width of an |\eqparbox| to use in % other \LaTeX{} commands. While the width can be determined by % creating an |\eqparbox| and using |\settowidth| to measure it, the % \textsf{eqparbox} package defines a convenience routine called % |\eqboxwidth| that achieves the same result. % % |\eqboxwidth| makes it easy to typeset something like % Table~\ref{tbl:mixed-tabular}. Table~\ref{tbl:mixed-tabular}'s only % column expands to fit the widest cell in the column, excluding the % final cell. The final cell's text word-wraps within whatever space is % allocated to it. In a sense, the first four cells behave as if they were % typeset in an~|l| column, while the final cell behaves as if it were % typeset in a~|p| column. In actuality, the column is an~|l| column; % an |\eqparbox| for the first four cells ensures the column stretches % appropriately, while a |\parbox| of width |\eqboxwidth{|\meta{tag}|}| % in the final cell ensures that the final cell word-wraps. % % \begin{table} % \centering % \caption{A \texttt{tabular} that stretches to fit some cells while % forcing others to wrap} % \label{tbl:mixed-tabular} % \DeleteShortVerb{\|} % \begin{tabular}{|@{}l@{}|} % \hline % \eqparbox[b]{wtab}{Wide} \\ \hline % \eqparbox[b]{wtab}{Wider} \\ \hline % \eqparbox[b]{wtab}{Wider than that} \\ \hline % \eqparbox[b]{wtab}{This is a fairly wide cell} \\ \hline % \parbox[b]{\eqboxwidth{wtab}}{\strut % While this cell's text wraps, the previous cells (whose text % doesn't wrap) determine the width of the column.} \\ \hline % \end{tabular} % \MakeShortVerb{\|} % \end{table} % % \section{Examples} % % Figure~\ref{fig:resume-excerpt}'s headings were typeset with the % following code: % % \begin{verbatim} % \noindent% % \eqparbox{place}{\textbf{Widgets, Inc.}} \hfill % \eqparbox{title}{\textbf{Senior Widget Designer}} \hfill % \eqparbox{dates}{\textbf{1/95--present}} % \end{verbatim} % \centerline{$\vdots$} % \begin{verbatim} % \noindent% % \eqparbox{place}{\textbf{Thingamabobs, Ltd.}} \hfill % \eqparbox{title}{\textbf{Lead Engineer}} \hfill % \eqparbox{dates}{\textbf{9/92--12/94}} % \end{verbatim} % \centerline{$\vdots$} % \bigskip % % \noindent % Table~\ref{tbl:sales-data} was entered as follows: % % \begin{verbatim} % \begin{tabular}{@{}lccc@{}} \hline % & \multicolumn{3}{c}{Sales (in millions)} \\ \cline{2-4} % \multicolumn{1}{c}{\raisebox{1ex}[2ex]{Product}} & % October & November & December \\ \hline % % Widgets & \eqparbox{oct}{\raggedleft 55.2 } & % \eqparbox{nov}{\raggedleft\textbf{ 89.2}} & % \eqparbox{dec}{\raggedleft 57.9 } \\ % Doohickeys & \eqparbox{oct}{\raggedleft\textbf{ 65.0}} & % \eqparbox{nov}{\raggedleft 64.1 } & % \eqparbox{dec}{\raggedleft 9.3 } \\ % Thingamabobs & \eqparbox{oct}{\raggedleft 10.4 } & % \eqparbox{nov}{\raggedleft 8.0 } & % \eqparbox{dec}{\raggedleft\textbf{109.7}} \\ \hline % \end{tabular} % \end{verbatim} % % \noindent % Note that the above can be simplified by defining a macro that % combines |\eqparbox| and |\raggedleft|. Furthermore, because the % numeric data being typeset are all approximately the same width, a % single tag could reasonably replace |oct|, |nov|, and |dec|. As it % stands, the code serves more as an illustration than as an optimal way % to typeset Table~\ref{tbl:sales-data}. % % Finally, Table~\ref{tbl:mixed-tabular} was typeset using the % following code: % % \begin{verbatim} % \begin{tabular}{|@{}l@{}|} % \hline % \eqparbox[b]{wtab}{Wide} \\ \hline % \eqparbox[b]{wtab}{Wider} \\ \hline % \eqparbox[b]{wtab}{Wider than that} \\ \hline % \eqparbox[b]{wtab}{This is a fairly wide cell} \\ \hline % \parbox[b]{\eqboxwidth{wtab}}{\strut % While this cell's text wraps, the previous cells (whose text % doesn't wrap) determine the width of the column.} \\ \hline % \end{tabular} % \end{verbatim} % % As an additional example, consider the paragraphs depicted in % Figure~\ref{fig:hang-indent}. We'd like the paragraph labels set on % the left, as shown, but we'd also like to allow both intra-~and % inter-paragraph page breaks. Of course, if the labels are made wider % or narrower, we'd like the paragraph widths to adjust automatically. % (Can any word processor do that, incidentally?) By using a custom % |list| environment which typesets its labels with |\eqparbox|, this is % fairly straightforward: % % \begin{figure}[tbp] ^^A NOT "here" (in case the default is changed) % \rule{\linewidth}{1pt} % \begin{list}{}{^^A % \renewcommand{\makelabel}[1]{\eqparbox[b]{listlab}{#1}}^^A % \setlength{\labelwidth}{\eqboxwidth{listlab}}^^A % \setlength{\labelsep}{2em}^^A % \setlength{\parsep}{2ex plus 2pt minus 1pt}^^A % \setlength{\itemsep}{0pt}^^A % \setlength{\leftmargin}{\labelwidth}^^A % \addtolength{\leftmargin}{\labelsep}^^A % \setlength{\rightmargin}{0pt}} % % \item[Stuff about me] I am great. Blah, blah, blah, blah, blah, % blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, % blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, % blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, % blah. % % \item[More stuff] I am wonderful. Blah, blah, blah, blah, blah, % blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, % blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, % blah. % % Did I mention that blah, blah, blah, blah, blah, blah, blah, blah, % blah, blah, blah, blah, blah, blah, blah? % % \item[The final exciting thing] I am fantastic. Blah, blah, blah, % blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, % blah, blah, blah, blah, blah, blah, blah, blah, blah. % \end{list} % \rule{\linewidth}{1pt} % \caption{Paragraphs with hanging indentation} % \label{fig:hang-indent} % \end{figure} % % \begin{verbatim} % \begin{list}{}{% % \renewcommand{\makelabel}[1]{\eqparbox[b]{listlab}{#1}}% % \setlength{\labelwidth}{\eqboxwidth{listlab}}% % \setlength{\labelsep}{2em}% % \setlength{\parsep}{2ex plus 2pt minus 1pt}% % \setlength{\itemsep}{0pt}% % \setlength{\leftmargin}{\labelwidth+\labelsep}% % \setlength{\rightmargin}{0pt}} % % \item[Stuff about me] I am great. Blah, blah, blah, ... % % \item[More stuff] I am wonderful. Blah, blah, blah, ... % % \item[The final exciting thing] I am fantastic. Blah, % blah, blah, ... % \end{list} % \end{verbatim} % % % \section{Limitations} % % Unfortunately, |\eqparbox| has a number of limitations not exhibited % by the original |\parbox| command. First, |\eqparbox| internally % typesets the given text within a |tabular| environment---specifically, % using ``|@{}l@{}|'' as the template---in order to determine the text's % natural width. Consequently, commands not valid within such a % |tabular| (e.g.,~list environments) are also not valid within the % \meta{text} argument of |\eqparbox|. As a corollary, an |\eqparbox| % can appear only where a |tabular| is also acceptable. % % A second limitation is that |\eqparbox| typesets its \meta{text} % argument \emph{twice}: once within a |tabular| to determine the % natural width and again within a parbox large enough to hold all text % associated with tag \meta{tag}. This approach may cause unexpected % results if \meta{text} is non-idempotent (i.e.,~has side % effects). For example, if \meta{text} increments a counter, the % counter will be incremented twice per invocation of |\eqparbox|. % % % \StopEventually{^^A % \section{Future Work} % % The following are some of the features people have requested I implement % in \textsf{eqparbox}: % % \begin{itemize} % \item Evalaute \texttt{\string\eqparbox}'s \meta{text} argument % exactly once in case it contains side effects. Currently, % \meta{text} is evaluated twice: once to determine its natural % size and once to put it in a parbox of the width associated with % the given tag. (Feature requested by Bernd Schandl.) % % \item Get \textsf{eqparbox} to work properly within an % \textsf{algorithmic} environment. (Feature requested by Mike % Shell.) % % \item Support pre-1999 \LaTeXe. (Feature requested by Mike Shell.) % \end{itemize} % % One idea I've been toying with that may resolve the first two items in % that list is to typeset \meta{text} within a parbox, then check % \texttt{\string\badness} to see if the box was too small for % \meta{text}. If not (i.e.,~the box was not overfull), then the % initial parbox can be reused directly without needing to re-typeset % \meta{text}. With this approach, \texttt{\string\eqparbox} will work % anywhere \texttt{\string\parbox} works. Unfortunately, I don't know % how to get at the \texttt{\string\badness} of the % \texttt{\string\hbox}es that comprise the \texttt{\string\vbox} % utilized by \texttt{\string\parbox}. If anyone has a suggestion, I'm % all ears. % % \PrintChanges % \PrintIndex % } % % \section{Implementation} % % The one-sentence summary of the implementation is, ``As % \textsf{eqparbox} goes along, it keeps track of the maximum width of % each box type, and when it's finished, it writes those widths to % the~|.aux| file for use on subsequent runs.'' If you're satisfied % with that summary, then read no further. Otherwise, get ready to % tackle the following annotated code listing. % % \begin{macrocode} %<*package> % \end{macrocode} % % \begin{macro}{\eqp@tempdima} % \begin{macro}{\eqp@tempdimb} % Define a couple temporary \meta{dimen}s for use in a variety of locations. % \begin{macrocode} \newlength{\eqp@tempdima} \newlength{\eqp@tempdimb} % \end{macrocode} % \end{macro} % \end{macro} % % \begin{macro}{\eqp@taglist} % Define a list of all of the tags we encountered in the author's document. % \begin{macrocode} \def\eqp@taglist{} % \end{macrocode} % \end{macro} % % \begin{macro}{\ifeqp@must@rerun} % \begin{macro}{\eqp@must@reruntrue} % \begin{macro}{\eqp@must@rerunfalse} % If an |eqparbox| is wider than the maximum-width |eqparbox| with the % same tag, we need to store the new maximum width and request that the % user re-run |latex|. We use |\ifeqp@must@rerun| and |\eqp@must@reruntrue| % to assist with this. % \begin{macrocode} \newif\ifeqp@must@rerun % \end{macrocode} % \end{macro} % \end{macro} % \end{macro} % % At the |\end{document}|, for each tag \meta{tag} we see if % |\eqp@next@|\meta{tag}, which was initialized to~|0.0pt|, is different % from |\eqp@this@|\meta{tag}, which was initialized to the maximum box % width from the previous run. If so, we issue an informational % message. In any case, we initialize the next run's % |\eqp@this@|\meta{tag} to |\eqp@next@|\meta{tag} and the next run's % |\eqp@next@|\meta{tag} to |0pt|. % \begin{macrocode} \AtEndDocument{% \begingroup % \end{macrocode} % \begin{macro}{\@elt} % The |\eqp@taglist| list is of the form ``|\@elt| |{|\meta{tag$_1$}|}| % |\@elt| |{|\meta{tag$_2$}|}|~\ldots''. We therefore locally define % |\@elt| to take the name of a tag and perform all of the checking % described above and then merely execute |\eqp@taglist|. % \changes{v2.0}{2004/08/01}{Modified to allow numbers in tag names % (suggested by Martin Vaeth)} % \begin{macrocode} \def\@elt#1{% \eqp@tempdima\csname eqp@this@#1\endcsname\relax \eqp@tempdimb\csname eqp@next@#1\endcsname\relax \ifdim\eqp@tempdima=\eqp@tempdimb \else \@latex@warning@no@line{Rerun to correct the width of eqparbox `#1'}% \fi \immediate\write\@auxout{% \string\expandafter\string\gdef\string\csname\space eqp@this@#1\string\endcsname{% \csname eqp@next@#1\endcsname }% ^^J% \string\expandafter\string\gdef\string\csname\space eqp@next@#1\string\endcsname{0pt}% }% }% \eqp@taglist \endgroup % \end{macrocode} % We output the generic ``rerun |latex|'' message if we encountered a % tag that was not present on the previous run. (This is always the % case on the first run or the first run after deleting the % corresponding |.aux| file. % \begin{macrocode} \ifeqp@must@rerun \@latex@warning@no@line{Rerun to correct eqparbox widths} \fi } % \end{macrocode} % \end{macro} % % \begin{macro}{\eqp@storefont} % \begin{macro}{\eqp@restorefont} % To find the natural width of a piece of text, we put it in a table and % take the width of that. The problem is that font changes are not % preserved across line breaks (table cells). We therefore define an % |\eqp@storefont| macro which itself defines an |\eqp@restorefont| % macro that restores the current font and font size to its current % state. % \begin{macrocode} \newcommand*{\eqp@storefont}{% \xdef\eqp@restorefont{% \noexpand\usefont{\f@encoding}{\f@family}{\f@series}{\f@shape}% \noexpand\fontsize{\f@size}{\f@baselineskip}% \noexpand\selectfont }% } % \end{macrocode} % \end{macro} % \end{macro} % % The following macro (|\eqp@settowidth|) requires the \textsf{array} % package's ability to inject code into every cell. % \begin{macrocode} \RequirePackage{array} % \end{macrocode} % % \begin{macro}{\eqp@settowidth} % This macro is just like |\settowidth|, but it puts its argument in a % |tabular|, which means that it can contain |\\|. We use the % \textsf{array} package's ``|>|'' and ``|<|'' template parameters to % inject an |\eqp@restorefont| at the start of every cell and an % |\eqp@storefont| at the end of every cell. Doing so preserves fonts % and font sizes across |\\| boundaries, just like |\parbox|. % \changes{v2.0}{2004/08/01}{Modified to store and restore the font % across \texttt{\string\string\string\\}~boundaries (suggested by % Mike Shell)} % \begin{macrocode} \newcommand{\eqp@settowidth}[2]{% \settowidth{#1}{{% \eqp@storefont \begin{tabular}{@{}>{\eqp@restorefont}l<{\eqp@storefont}@{}}% #2% \end{tabular}% }}% } % \end{macrocode} % \end{macro} % % \begin{macro}{\eqparbox} % \begin{macro}{\eqparbox@i} % \begin{macro}{\eqparbox@ii} % We want |\eqparbox| to take the same arguments as |\parbox|, with the % same default values for the optional arguments. The only difference % in argument processing is that |\eqparbox| has a \meta{tag} argument % where |\parbox| has \meta{width}. % % Because |\eqparbox| has more than one optional argument, we can't use % a single function defined by |\DeclareRobustCommand|. Instead, we % have to split |\eqparbox| into the following four macros: % % \begin{description} % \item[\texttt{\string\eqparbox}] Takes zero or more optional arguments. % First optional argument defaults to~|c|. Calls |\eqparbox@i|. % % \item[\texttt{\string\eqparbox@i}] Takes one or more optional arguments. % Second optional argument defaults to~|\relax|. Calls |\eqparbox@ii|. % % \item[\texttt{\string\eqparbox@ii}] Takes two or more optional arguments. % Third optional argument defaults to~|s| if either of the first two % arguments is absent or to the first argument if both are present. % Calls |\eqparbox@iii|. % % \item[\texttt{\string\eqparbox@iii}] Takes three optional arguments % and two mandatory arguments. Does all the work for |\eqparbox|. % \end{description} % % \noindent % Note the direct correspondence between these macros and % |ltboxes.dtx|'s |\parbox|, |\@iparbox|, |\@iiparbox|, and % |\@iiiparbox| macros. % \begin{macrocode} \DeclareRobustCommand\eqparbox{% \@ifnextchar[%] {\eqparbox@i}% {\eqparbox@iii[c][\relax][s]}% } \def\eqparbox@i[#1]{% \@ifnextchar[%] {\eqparbox@ii[#1]}% {\eqparbox@iii[#1][\relax][s]}% } \def\eqparbox@ii[#1][#2]{% \@ifnextchar[%] {\eqparbox@iii[#1][#2]}% {\eqparbox@iii[#1][#2][#1]}% } % \end{macrocode} % \end{macro} % \end{macro} % \end{macro} % % \begin{macro}{\eqparbox@iii} % The following function does all the real work for |\eqparbox|. It takes % five parameters---\meta{pos}, \meta{height}, \meta{inner-pos}, % \meta{tag}, and \meta{text}---and ensures that all boxes with the same % tag will be as wide as the widest box with that tag. % % To keep track of box widths, |\eqparbox| makes use of two global % variables for each tag: |\eqp@this@|\meta{tag} and % |\eqp@next|\meta{tag}. |\eqp@this@|\meta{tag} is the maximum width % ever seen for tag \meta{tag}, including in previous |latex| runs. % |\eqp@next@|\meta{tag} works the same way but is always initialized % to~|0.0pt|. It represents the maximum width to assume in % \emph{subsequent} |latex| runs. It is needed to detect whether the % dest text with tag \meta{tag} has been removed/shrunk. At the end of % a run, \textsf{eqparbox} prepares the next run (via the~|.aux| file) % to initialize |\eqp@this@|\meta{tag} to the final value of % |\eqp@next@|\meta{tag}. % \changes{v2.0}{2004/07/30}{Removed extraneous \texttt{\string\string\string\global}s % (suggested by David Kastrup)} % \begin{macrocode} \def\eqparbox@iii[#1][#2][#3]#4#5{% \eqp@settowidth{\eqp@tempdimb}{#5}% \expandafter \ifx\csname eqp@this@#4\endcsname\relax % \end{macrocode} % If we get here, then we've never encountered tag \meta{tag}, even in a % previous |latex| run. We request that the user re-run |latex| This is % not always necessary (e.g., when all uses of the |\eqparbox| with tag % \meta{tag} are left-justified), but it's better to be safe than sorry. % \begin{macrocode} \global\eqp@must@reruntrue \expandafter\xdef\csname eqp@this@#4\endcsname{\the\eqp@tempdimb}% \expandafter\xdef\csname eqp@next@#4\endcsname{\the\eqp@tempdimb}% \else % \end{macrocode} % If we get here, then we \emph{have} previously seen tag \meta{tag}. % We just have to keep track of the maximum text width associated with % it. % \begin{macrocode} \eqp@tempdima=\csname eqp@this@#4\endcsname\relax \ifdim\eqp@tempdima<\eqp@tempdimb \expandafter\xdef\csname eqp@this@#4\endcsname{\the\eqp@tempdimb}% \global\eqp@must@reruntrue \fi % \end{macrocode} % \begin{macrocode} \eqp@tempdima=\csname eqp@next@#4\endcsname\relax \ifdim\eqp@tempdima<\eqp@tempdimb \expandafter\xdef\csname eqp@next@#4\endcsname{\the\eqp@tempdimb}% \fi \fi % \end{macrocode} % % The first time we encounter tag \meta{tag} in the current document we % ensure \LaTeX{} will notify the user if he needs to re-run |latex| on % account of that tag. % \begin{macrocode} \@ifundefined{eqp@seen@#4}{% \expandafter\gdef\csname eqp@seen@#4\endcsname{}% \@cons\eqp@taglist{{#4}}% }{}% % \end{macrocode} % % Finally, we can call |\parbox|. We pass it \meta{pos}, \meta{height}, % \meta{inner-pos}, and \meta{text} directly, and we pass it % |\eqp@this@|\meta{tag} for its \meta{width} argument. % \begin{macrocode} \eqp@tempdima=\csname eqp@this@#4\endcsname\relax \parbox[#1][#2][#3]{\eqp@tempdima}{#5}% } % \end{macrocode} % \end{macro} % % \begin{macro}{\eqboxwidth} % For the times that the user wants to make something other than a box % match an |\eqparbox|'s width, we provide |\eqboxwidth|. |\eqboxwidth| % returns the width of a box corresponding to a given tag. More % precisely, if |\eqp@this@|\meta{tag} is defined, it's returned. % Otherwise,~|0pt| is returned. % \changes{v2.1}{2004/08/02}{Rewrote so as to be compatible with the % \textsf{calc} package's \texttt{\string\string\string\setlength} % command (problem initially reported by Gary L. Gray and narrowed % down by Martin Vaeth)} % \begin{macrocode} \newcommand*{\eqboxwidth}[1]{% \@ifundefined{eqp@this@#1}{0pt}{\csname eqp@this@#1\endcsname}% } % \end{macrocode} % \end{macro} % % \DeleteShortVerb{\|} % \MakeShortVerb{\!} % \paragraph{Per-tag memory usage} % The \textsf{eqparbox} package defines three macros for each unique % tag: !\eqp@this@!\meta{tag}, !\eqp@next@!\meta{tag}, and % !\eqp@seen@!\meta{tag}. Consequently, each unique tag subtracts three % strings from \TeX's string pool and three multiletter control % sequences from that pool. In addition, each unique tag \meta{tag} % subtracts $|!\eqp@this@!| + |\meta{tag}| + |!\eqp@next@!| + % |\meta{tag}| + |!\eqp@seen@!| + |\meta{tag}| = 27 + 3 \times % |\meta{tag}|$ string characters from \TeX's pool of string characters. % For example, a document that invokes !\eqparbox! with tags % ``!hello!'' and ``!goodbye!'' will utilize $3 \times 2 = 6$ strings, % $3 \times 2 = 6$ multiletter control sequences, and $(27 + 3 \times 5) % + (27 + 3 \times 7) = 90$ \TeX{} string characters. % \DeleteShortVerb{\!} % \MakeShortVerb{\|} % % \begin{macrocode} % % \end{macrocode} % % \Finale %