* %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % TeX commands for typesetting this document % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \input inputd.tip \InputD{ts-logo.tip} \InputD{ts-lazy.tip} \InputD{parin.tip} \InputD{parv-1.tip} %\InputD{label-ll-w1.tip} \InputD{enumlist.tip} % define my style % \codemargin=20pt \twopagelayouttrue % % descriptions are environments with label paragraphs, where the % labels are set by means of an \item{label} macro call. \let\DescriptionItem=\ItemLL \newskip\descrskip \descrskip=5pt plus 4pt \newdimen\descrmargin \descrmargin=10mm \def\description{% \BeginAList{\descrmargin}{2mm}{\descrmargin}{\descrskip}% {0.5\descrskip}{0.25\descrskip}{0pt}% \parskip=0pt \def\item##1{\DescriptionItem{\bf##1}}% }% \def\enddescription{\EndAList} % enumerations are environments with numbered paragraphs \catcode\@=11 \newskip\enumskip \enumskip=5pt plus 3pt \def\@BeginEnumerateLevelOne{% \BeginAList{5mm}{2mm}{1em}{\enumskip}% {0.5\enumskip}{0.25\enumskip}{0pt}% }% \let\@BeginEnumerateLevelTwo=\@BeginEnumerateLevelOne \let\@BeginEnumerateLevelThree=\@BeginEnumerateLevelOne \let\@BeginEnumerateLevelFour=\@BeginEnumerateLevelOne %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Beginning of document proper % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \input title \let\normalDSChead=\DSCHeader \def\DSCHeader{\hfil} \title{% \Large\bf\baselineskip=20pt {\tt nwsup.nw}\\ Macro Support Files\\for\\plain {\TeX} {\tt noweb}\\ {\normal\rm by}\\ \large\bf A. J. Hurst\\ \rm Department of Computer Science\\ Monash University\\ Version 1.0 *}% \vfil\eject \pageno=1 \let\DSCHeader=\normalDSChead \section{Overview} This document describes the {\TeX} macro code that supports {\tt noweave} and {\tt noweb}. It defines a file, called nwmac.tex, also known as the root document *'' of this (literate) program.
<*>=
<nwmac.tex>

This code is written to a file (or else not used).

*\subsection{Usage} These macros are intended for use with {\tt noweave} and {\tt noweb}, and are not particularly useful in their own right. This document exists to describe the organization and behaviour of the macros herein. In use, the macros read in the {\TeXIP} macros required, and documents from noweave need no other support than these macros and plain {\TeX}. However, this document itself does use a number of other macros from {\TeXIP}.

<nwmac.tex>=
% nwmac.tex -- plain TeX support for noweb
% DON'T read or edit this file!  Use the file nwsup.nw instead.

Used above; next definition.

*\subsection{Copyright} The original versions of these macros were written for {\LaTeX} by Norman Ramsey and are copyright by him. This version by John Hurst, 1995.

<nwmac.tex>+=
% copyright Norman Ramsey, 1991 (original LaTeX macros)
% modified for plain Tex by John Hurst, 1995

Used above; previous and next definitions.

\subsection{Background} These macros have been modified from Norman Ramsey's {\tt support.nw} document, by removing all {\LaTeX} specific material, and modifying the plain {\TeX} macros appropriately. They have been rewritten to provide cross referencing and indexing, using much of the {\LaTeX} code, together with some macros from {\TeXIP}, the four volume series \TeXIP" by Stephan von Bechtolsheim, published in 1993 by Springer-Verlag, New York. \subsection{Components} This document is structured into a number of sections, and, as far as possible, the literate program structure follows the documentation structure, namely: \begingroup \parskip=0pt \advance\rightskip by 10pt \advance\leftskip by 30pt Overview (this section)\par Document Style Parameters\par \begingroup\advance\leftskip by 30pt Page Style\par Chunk Style\par \endgroup Options\par Initialization\par Type Setting Management\par \begingroup\advance\leftskip by 30pt Two Column Handling\par Page-breaking Strategy\par \endgroup Chunk Management\par Labels\par \begingroup\advance\leftskip by 30pt Basic Referencing\par Sub-page Referencing\par WEB numbering\par \endgroup Cross Referencing\par \begingroup\advance\leftskip by 30pt Chunks\par Identifiers\par Support\par \endgroup Indexing\par \begingroup\advance\leftskip by 30pt Chunks\par Identifiers\par \endgroup Support Routines\par Finalization\par Startup Processing\par Miscellaneous\par \endgroup

<nwmac.tex>+=
<Document Style Parameters>
<Initialization For Macros>
<Type Setting Management>
<Chunk Management>
<Labels>
<Cross Referencing of Chunks and Identifiers>
<Chunk Index Construction>
<Housekeeping and Support Routines>
<other stuff not yet updated>
<Finalizing and Washup>
<Startup Processing>


Used above; previous definition.

% **** Document Style Parameters *************************************** \section{Document Style Parameters} Make @ a letter so that we can use private' macro names.

<Document Style Parameters>=
\catcode\@=11
<Page Style Parameters>
<Chunk Style Parameters>

Used above.

*\subsection{Page Style Parameters} Define the \\nwpagewidth, which is the width of (normal) text on a page. \nwpageheight is the height of text on a page.

<Page Style Parameters>=
\newdimen\nwpagewidth   \nwpagewidth=\hsize
\newdimen\nwpageheight  \nwpageheight=\vsize

Defines \nwpageheight, \nwpagewidth (links are to index).

Used above; next definition.

* Standard paragraph separation \parskip and first line indentation \parindent are reset for documentation chunks.

<Page Style Parameters>+=
\parskip=16pt
\parindent=0pt

Used above; previous and next definitions.

The conditional \iftwopagelayout allows the user to switch on a double sided mode of page layout, in which the page number in the heading switches from side to side. The default is single sided mode (no switching).

<Page Style Parameters>+=
\newif\iftwopagelayout\twopagelayoutfalse

Used above; previous definition.

*\subsection{Chunk Style Parameters} \codemargin is the amount by which code listings are indented from the normal margin. \nwtagstyle determines the style in which tags are displayed. \codemargin, may be reset by the user if she desires a different setting. This reset should be placed before the first code chunk that should be indented.

<Chunk Style Parameters>=
\newdimen\codemargin    \codemargin=20pt
\def\nwtagstyle{\footnotesize\rm}%

Defines \codemargin, \nwtagstyle (links are to index).

Used above; next definition.

* We make the \hsize parameter for code sufficient for 88 columns. Well, 91 actually, but Norman wasn't sure why the extra bit.

<Chunk Style Parameters>+=
\setbox0=\hbox{\tt m}
\newdimen\codehsize     \codehsize=91\wd0

Defines \codehsize (links are to index).

Used above; previous and next definitions.

* \defspace is the space we would like on the right of navigational info that appears on definition lines, so that it lines up with the text above and below.

<Chunk Style Parameters>+=
\newdimen\nwdefspace    \nwdefspace=\codehsize
\relax


Used above; previous and next definitions.

\nwmarginglue defines how far into the left margin a chunk tag is placed. \nwtagstyle determines how it is printed.

<Chunk Style Parameters>+=
\newdimen\nwmarginglue\nwmarginglue=7.5mm
\def\nwtagstyle{\bf}%

Defines \nwmarginglue, \nwtagstyle (links are to index).

Used above; previous definition.

* % **** Options ********************************************************* \section{Options} Not much defined in this section as yet. % **** Initialization ************************************************** \section{Initialization} Include the {\TeXIP} macros.

<Initialization For Macros>=
\input inputd.tip
\InputD{inputc.tip}
\InputD{ts-fonts.tip}
\InputD{list-mac.tip}
\InputD{namedef.tip}
\InputD{printco.tip}
<Type Setting Initialization>

Used above; next definition.

We need some redefinitions for compatibility between TiP and noweave.

<Initialization For Macros>+=
\catcode\@=11
\let\@namedef=\NameDef
\let\@nameuse=\NameUse

Defines \@namedef, \@nameuse (links are to index).

Used above; previous and next definitions.

Define the macro that appears at the start of each input file. The markup program and filters put this filename' flag at the start of the text. This is used to generate an appropriate banner to each page.

<Initialization For Macros>+=
\def\nwfilename#1{%
\vfil\eject% start a new page for this file
\mark{#1}% set the banner for this and subsequent pages
}%

Defines \nwfilename (links are to index).

Used above; previous definition.

* % **** Type Setting Management ******************************************* \section{Type Setting Management} *\subsection{Two Column Handling} Most of the document is set in single column mode, however, for the indices we wish to provide a two-column mode. This is imported from the {\TeXIP} macros. Since the double column macro defines its own ({\TeX}) output routine, we have to setup the page size and header and footer lines as well.

<Type Setting Initialization>=
\InputD{out-ds.tip}%
\SetUpDSC{\nwpagewidth}{0.45\nwpagewidth}{0pt}{\nwpageheight}{1}{0}%
\iftwopagelayout
\ifodd\pageno
\else
\fi
\else
\fi
}%
\def\DSCFooter{\hfil}%
\catcode\@=11% reset to allow @ in macro names

Used above; next definition.

We allow alternating headings for double sided printing. Only difference between the two is the order of file name, date and page number, which is reversed for the left hand side of a page spread.

<Right Page Heading>=
\hbox to \nwpagewidth{%
\tentt\firstmark
\hfil
\tenrm\today
\hbox to 4em{\hss\folio}%
}%

Used above.

<Left Page Heading>=
\hbox to \nwpagewidth{%
\hbox to 4em{\folio\hss}%
\tenrm\today
\hfil
\tentt\firstmark
}%

Used above.

We start off in single column mode by default. Since the double-column macros also redefine \bye, we should save that for later use when we redefine \bye!

<Type Setting Initialization>+=
\let\DSC@bye=\bye

Used above; previous definition.

\subsection{Page-breaking strategy} We want to insert penalties aiming for: \enumskip=0pt\BeginEnumerate \Item No page breaks in the middle of a code chunk unless necessary to avoid an overfull vbox; \Item Documentation immediately preceding a code chunk should appear on the same page as that code chunk unless doing so would violate rule 1. \EndEnumerate \filbreak is useful for this sort of thing (see {\it The {\TeX} book\/}) and is used to encourage breaks at the right places between chunks. Appropriate penalties are inserted elsewhere, between code lines in particular. \eatline is used to consume newlines that should be ignored, for example, the newlines at the end of @ %def {\it identifiers} lines. I can't remember what \startline or \newlines are for; I don't think {\tt noweave} ever emits them.

<Type Setting Management>=
{%
\catcode\^^M=\active % make CR an active character
\gdef\newlines{%
\catcode\^^M=\active % make CR an active character
\def^^M{\par\startline}%
}%
\gdef\eatline#1^^M{\relax}%
}%
%%% DON'T   \gdef^^M{\par\startline}}% in case ^^M appears in a \write
\def\startline{%
\noindent\hskip\parindent\ignorespaces
}%
\def\nwnewline{%
\ifvmode
\else\hfil\break
\fi
}%

Defines \eatline, \newlines, \nwnewline, \startline (links are to index).

Used above.

* % **** Chunk Management ************************************************ *\section{Chunk Management} Here are the basics of the literate programming style. The alternation of document and code chunks is managed by the environment macros \nwbegindocs,\nwenddocs which bracket documentation chunks, and \nwbegincode,\nwendcode which bracket code chunks. It is not essential that documentation and code are strictly alternating, they can be interleaved in arbitrary order. Start a documentation chunk. This is a good place to break, hence the \filbreak.

<Chunk Management>=
\def\nwbegindocs#1{%
\filbreak
}%

Defines \nwbegindocs (links are to index).

Used above; next definition.

End a documentation chunk. Not much to it, really.

<Chunk Management>+=
\def\nwenddocs{%
\par
}%

Defines \nwenddocs (links are to index).

Used above; previous and next definitions.

Start a code chunk. A bit more involved, as we have to begin a group (which gets closed by the matching \nwendcode), and set up the environment for typesetting that code (sse chunk \subref{ref:setupcode}).

<Chunk Management>+=
\def\nwbegincode#1{%
\par\nobreak
\begingroup% matching \endgroup appears in \nwendcode
\setupcode
\newlines
\parindent=0pt\parskip=0pt
\let\oendmoddef=\endmoddef
\let\oplusendmoddef=\plusendmoddef
\def\endmoddef{\oendmoddef\par}%
\def\plusendmoddef{\oplusendmoddef\par}%
\hsize=\codehsize
\noindent\bchack
}%

Defines \nwbegincode (links are to index).

Used above; previous and next definitions.

End a code chunk

<Chunk Management>+=
\def\nwendcode{%
\endgroup
}%

Defines \nwendcode (links are to index).

Used above; previous and next definitions.

Don't really know what a \nwdocspar does.

<Chunk Management>+=
\def\nwdocspar{%
\par\semifilbreak
}%

Defines \nwdocspar (links are to index).

Used above; previous and next definitions.

<Chunk Management>+=
\def\semifilbreak{%
\vskip0pt plus1.5in
\penalty-200
\vskip0pt plus -1.5in
}%
\raggedbottom

Defines \semifilbreak (links are to index).

Used above; previous and next definitions.

* *\sublabel{ref:setupcode}% Most code is set in an environment in which \setupcode has been executed. In this environment, only \, {, and } have their usual categories; every other character represents itself. Appropriate \chardefs ensure that the special characters can be escaped with a backslash.

<Chunk Management>+=
\chardef\other=12
\def\setupcode{%
\chardef\\=\\
\chardef\{=\{
\chardef\}=\}
\catcode\$=\other \catcode\&=\other \catcode\#=\other \catcode\%=\other \catcode\~=\other \catcode\_=\other \catcode\^=\other \obeyspaces\tt }  Defines \setupcode (links are to index). Used above; previous and next definitions. * Within a code environment, it may be necessary to restore the category codes in order to set a module (chunk) name. <Chunk Management>+= {\obeyspaces\global\let =\ }% from texbook, p 381 \def\setupmodname{% \catcode\$=3
\catcode\&=4
\catcode\#=6
\catcode\%=14
\catcode\~=13
\catcode\_=8
\catcode\^=7
\catcode\ =10
\catcode\^^M=5
\rm
}%

Defines \setupmodname (links are to index).

Used above; previous and next definitions.

* *{\tt noweave} brackets uses of chunk names with \LA and \RA, which handle the angle brackets, font, and environment. As it stands, chunk names can be broken across lines (or pages). This could result in unnecessary page breaks in code. \let\\maybehbox=\hbox to avoid breaking them (or to make them work in math mode); this is done in code chunks, but could be done in general.

<Chunk Management>+=
\def\LA{\begingroup\maybehbox\bgroup\setupmodname\it$\langle$}
\def\RA{\/$\rangle$\egroup\endgroup}
\def\code{%
\leavevmode
\begingroup
\setupcode
\newlines
}%
\def\edoc{%
\endgroup
}%
\let\maybehbox\relax

Defines \LA, \RA, \code, \edoc, \maybehbox (links are to index).

Used above; previous and next definitions.

* \equivbox and \plusequivbox are used to set the \unhcopy\equivbox'' and \unhcopy\plusequivbox'' that open a chunk definition or its continuation. {\tt noweave} brackets definitions of chunk names with \moddef and either \endmoddef or \plusendmoddef.

<Chunk Management>+=
\newbox\equivbox
\setbox\equivbox=\hbox{$\equiv$}%
\newbox\plusequivbox
\setbox\plusequivbox=\hbox{$\mathord{+}\mathord{\equiv}$}%

Defines \equivbox, \plusequivbox (links are to index).

Used above; previous and next definitions.

\moddef can't have an argument because there might be \code$\ldots$\edoc nested within the argument.

<Chunk Management>+=
\def\moddef{%
\leavevmode
\kern-\codemargin
\LA
}%

Defines \moddef (links are to index).

Used above; previous and next definitions.

<Chunk Management>+=
\def\endmoddef{
\RA
\ifmmode \equiv
\else \unhcopy\equivbox
\fi
\nobreak\hfill\nobreak
}%

Defines \endmoddef (links are to index).

Used above; previous and next definitions.

<Chunk Management>+=
\def\plusendmoddef{%
\RA
\ifmmode \mathord{+}\mathord{\equiv}%
\else \unhcopy\plusequivbox
\fi
\nobreak\hfill\nobreak
}%

Defines \plusendmoddef (links are to index).

Used above; previous and next definitions.

* \bchack ({\it b\/}egin {\it c\/}ode {\it hack} serves to consume the carriage return following the \nwbegincode start environment macro.

<Chunk Management>+=
{%
\catcode\^^M=\active % make CR an active character
\gdef\bchack#1^^M{\relax#1}%
}%

Defines \bchack (links are to index).

Used above; previous definition.

* % **** Labels ********************************************************** \section{Labels} \subsection{Basic Referencing Macros} {\LaTeX} supplies the macros \ref and \pageref to do cross referencing. We need to supply definitions for these. The basic principle of cross referencing is to plant {\it label\/}s in the source text that identify the places that we want to talk about. Along with the label, we can give a user-defined {\it name}. Then the \ref macro is used to reference that place by name, and \pageref is used to refer to the location by page number. Here's the macro to plant a label. I pinched this straight from {\LaTeX}, and commented out the bits not needed.

<Labels>=
\def\label#1{%
%\@bsphack
%\if@filesw
{%
\let\thepage\relax
\def\protect{\noexpand\noexpand\noexpand}%
\xdef\@gtempa{%
\write\@auxout{%
\string\newlabel{#1}{{0}{\thepage}}%
}%
}%
}%
\@gtempa
%\if@nobreak
\ifvmode\nobreak\fi
%\fi
%\fi
%\@esphack
}%

Defines \label (links are to index).

Used above; next definition.

\ref takes a single parameter which is a label, and generates the name. If the label has not been defined, an error message is issued, and the name represented by two question marks.

<Labels>+=
\def\ref#1{%
\@ifundefined{r@#1}%
{{\bf ??}<warn of undefined reference to #1>}%
{\expandafter\expandafter\expandafter
\@car\csname r@#1\endcsname\@nil\null}%
}%

Defines \ref (links are to index).

Used above; previous and next definitions.

\pageref is the same as \ref, except that it generates the page number of the location of the referenced label.

<Labels>+=
\def\pageref#1{%
\@ifundefined{r@#1}%
{{\bf ??}<warn of undefined reference to #1>}%
{\expandafter\expandafter\expandafter
\@cdr\csname r@#1\endcsname\@nil\null}%
}%
\def\@refpair#1{%
\@ifundefined{r@#1}%
{{0}{0}<warn of undefined reference to #1>}%
{\@nameuse{r@#1}}%
}%

Defines \pageref, \@refpair (links are to index).

Used above; previous and next definitions.

<warn of undefined reference to #1>=
\@warning{Reference #1' on page \thepage \space undefined}


Used below (1), below (2).

\subsection{Sub-page references} This is the wonderful code that Dave Love provided to make page references like 7a, 7b, and so on. This code provides a mechanism for defining page sub-references' using \sublabel{foo} referenced with \subpageref{foo}. Sub-references will be numbered like these real examples: \subpageref{ref:foo}, \subpageref{ref:bar}, \subpageref{ref:baz}\sublabel{ref:foo}\sublabel{ref:bar}\sublabel{ref:baz} etc.\ unless there is only one on the page, in which case the letter will be dropped like this: \subpageref{ref:fred}. To be able to use \subpageref we must define the label with \sublabel, used like label. (Using \ref with a label defined by \sublabel will produce the sub-reference number, by the way, and \pageref works as expected.) Note that \subpageref is robust and \ref and \pageref are redefined to be robust also, as they will be in future \LaTeX{} releases. Incidentally, these expand to the relevant text plus \null---you might want to strip this off, e.g.\ for sorting lists. There are various ways we could attack this task (which is made non-trivial by the well-known asynchrony of (La)\TeX's output routine), but they all must depend on hacks in the .aux file or a similar one. Joachim Schrod's fnpag.sty does the same sort of thing differently to this \LaTeX-specific approach. See latex.tex for enlightenment on the cross-referencing mechanism and the \LaTeX{} internals used below. [DL: The internals change in \LaTeX2e compared with \LaTeX~2.09. The code here still works, though.] The \subpageref macro first does a normal \pageref. If the reference is actually defined, it then goes on to check whether the control sequence 2on\LA{}{page referenced}\RA{} is defined and sets the \ref value to get a etc.\ if so. The magic, of course, is in defining the 2on bit appropriately. Define a \subref to be the same as a \subpageref

<Labels>+=
\def\subref#1{%
\subpageref{#1}%
}%

Defines \subref (links are to index).

Used above; previous and next definitions.

<Labels>+=
\def\subpageref#1{%
\@ifundefined{r@#1}%
{%
\pageref{#1}%
}%
{%
\@ifundefined{2on\@pageref{#1}}%
{%
%\edef\@spref{\@subref{#1}}
%\expandafter\nwthepagenum\@spref
\pageref{#1}%
}%
{%
\expandafter\expandafter\expandafter
\nwthepagenum\csname r@#1\endcsname
}%
}%
}%

Defines \subpageref (links are to index).

Used above; previous and next definitions.

* \@subref is a hangover from the {\LaTeX} version, and could well be reinstated, except that I now achieve the same thing (I hope!) by directly calling the \pageref macro. The difference is whether the label is used directly (current), or whether the stored page in the list associated with the label is used. (See \ref{ref:sublabel}.)

<Labels>+=
\def\@subref#1{%
\edef\@tempb{\@car\csname r@#1\endcsname\@nil}%
\@tempb
%\message{\string\@subref:\noexpand\@tempb}%
}%

Defines \@subref (links are to index).

Used above; previous and next definitions.

* \subpagepair produces a {subpage}{page} pair.

<Labels>+=
\def\subpagepair#1{%  % produces {subpage}{page}
\@ifundefined{r@#1}%
{{0}{0}}%
{%
\@ifundefined{2on\@pageref{#1}}%
{{0}{\expandafter\expandafter\expandafter
\@cdr\csname r@#1\endcsname\@nil}}%
{\@nameuse{r@#1}}%
}%
}%

Defines \subpagepair (links are to index).

Used above; previous and next definitions.

* \@pageref is like \pageref, but it expands to \relax without a warning if the reference is undefined.

<Labels>+=
\def\@pageref#1{%
\expandafter\expandafter\expandafter
\@cdr\csname r@#1\endcsname\@nil
}%

Defines \@pageref (links are to index).

Used above; previous and next definitions.

* \subsubsection{The \sublabel macro}\label{ref:sublabel} \sublabel is called with just one argument, unlike \Label. This is because it computes the second argument to \Label itself. The argument is the label name. The whole effect of this is that labels map to a pair of values, the first of which is, in the case of ordinary labels, a user defined value, and the second of which is the page number. Here, when using sublabels', the first argument becomes the subpage chunk number, and this is automatically computed. This is a major change from the algorithm used in the {\LaTeX} case, where labels are mapped to a pair of values, as above, but where the first value is itself a tuple value containing the subpage number, and then the page number, follwed by the second value, which is the page number again! This duplication seemed unnecessary, and so I removed it. Perhaps there was a deeper need for it in {\LaTeX}? If so, I couldn't find it in the documentation above. There is a need to also practice what is preached! \sublabel is like the \label command, except that it writes \newsublabel onto the .aux file rather than \newlabel.

<Labels>+=
\def\sublabel#1{%
%\@bsphack
%\if@filesw
{%
\let\thepage\relax
\def\protect{\noexpand\noexpand\noexpand}%
\edef\@tempa{%
\write\@auxout{\string\newsublabel{#1}{{}{\thepage}}}
}%
\expandafter
}%
\@tempa
%\if@nobreak
\ifvmode\nobreak\fi
%\fi
%\fi
%\@esphack
}%

Defines \sublabel (links are to index).

Used above; previous and next definitions.

* \nosublabel creates a label with a sub-page part of~0.

<Labels>+=
\def\nosublabel#1{%
%\@bsphack
%\if@filesw
{%
\let\thepage\relax
\def\protect{\noexpand\noexpand\noexpand}%
\edef\@tempa{%
\write\@auxout{\string\newlabel{#1}{{0}{\thepage}}}%
}%
\expandafter
}%
\@tempa
%\if@nobreak
\ifvmode\nobreak\fi
%\fi
%\fi
%\@esphack
}%

Defines \nosublabel (links are to index).

Used above; previous and next definitions.

* \newsublabel is the macro that does the important work. It is called with the same sort of arguments as \newlabel: the first argument is the label name and the second is {\LA ref value}{page number\RA}. (Note that the only definition here which needs to be global is the one which is, and that \global is redefined by \enddocument, which will bite you if you use it\dots)

<Labels>+=
<definition of \newsublabel>

Used above; previous and next definitions.

First we extract the page number into \this@page.

<definition of \newsublabel>=
\def\newsublabel#1#2{%
\edef\this@page{\@cdr#2\@nil}%
% definition continues

Defines \newsublabel (links are to index).

Used below; next definition.

Then we see whether it's changed from the value of \last@page which was stashed away by the last \newsublabel (or is \relax if this is the first one). If the page has changed, we reset the counter \sub@page telling us how many sub-labels there have been on the page.

<definition of \newsublabel>+=
\ifx\this@page\last@page
\else\sub@page=0
\fi
\edef\last@page{\this@page}%

Used below; previous and next definitions.

If we've had at least two on the page, we define the 2on\LA{}{page no.}\RA{} macro to indicate the fact.

<definition of \newsublabel>+=
\ifnum\sub@page=2
\global\@namedef{2on\this@page}{}%
\fi

Used below; previous and next definitions.

Then we write a normal \newlabel with the sub-reference as the normal reference value in the second argument.

<definition of \newsublabel>+=
\edef\@tempa{%
\noexpand\newlabel{#1}%
{%
{\number\sub@page}{\this@page}%
}%
}%
\@tempa
}%

Used below; previous definition.

Define the \last@page macro, which expands to the page number of the last chunk number, or to \relax if no previous chunk label defined. \sub@page counts the number of chunk labels on the current page. \thepage is simply a convenient redefinition.

<Labels>+=
\def\last@page{\relax}%
\newcount\sub@page
\def\thepage{\the\pageno}%

Defines \last@page, \sub@page, \thepage (links are to index).

Used above; previous and next definitions.

Define the newlabel macro

<Labels>+=
\def\newlabel#1#2{%
\@ifundefined{r@#1}%
{}%
{\@warning{Label #1' multiply defined}}%
\global\@namedef{r@#1}{#2}%
}%
\def\@newlabel#1#2#3{%
\NameDef{r@#1}{{#2}{#3}}%
}%

Defines \@newlabel, \newlabel (links are to index).

Used above; previous and next definitions.

* Now for the referencing of subpages. The \subref and \subpageref macros are equivalent. If the reference is actually defined, it then goes on to check whether the control sequence 2on\LA{}{page referenced}\RA{} is defined and sets the \ref value to get a etc.\ if so. The magic, of course, is in defining the 2on bit appropriately. (AJH) Yes, but this doesn't exactly explain what the purpose of the 2on bit is! \subsubsection{Margin Identification of Chunks} So that chunks can be easily identified, a marginal indication of the chunk number is given. This is in the form of a page number and subpage label, derived from looking up the label \subpageref reference. The left end of the label is displaced \nwmarginglue from the current left margin, and typeset according to the definition of \nwtagstyle. The kerning to the indented codemargin \codemargin should really be done in \moddef, I think (AJH). \moddef is defined in the \LA kernel\RA part of this document. The macros are invoked by the typical {\TeX} fragment: \begin{verbatim} \nwbegincode{2} \sublabel{NWtt.5-cod4-1} \nwmargintag{{\nwtagstyle{}\subpageref{NWtt.5-cod4-1}}} \moddef{code~{\nwtagstyle{}\subpageref{NWtt.5-cod4-1}}}\endmoddef \end{verbatim} \nwmargintag places a chunk label in the margin.

<Labels>+=
\def\nwmargintag#1{%
\leavevmode
\llap{#1\kern\nwmarginglue\kern\codemargin}%
}%

Defines \nwmargintag (links are to index).

Used above; previous and next definitions.

* *\subsubsection{Styles for Formatting Sub-page Numbers} Here a a couple of hooks for formatting sub-page numbers, which can be alphabetic, numeric, roman, or omitted.

<Labels>+=
\def\@alphasubpagenum#1#2{#2\ifnum#1=0 \else\alph{#1}\fi}
\def\@nosubpagenum#1#2{#2}
\def\@numsubpagenum#1#2{#2\ifnum#1=0 \else.\arabic{#1}\fi}
\def\@romansubpagenum#1#2{#2\ifnum#1=0 \else.\roman{#1}\fi}
\def\nwopt@nosubpage{\let\nwthepagenum=\@nosubpagenum\nwopt@nomargintag}
\def\nwopt@numsubpage{\let\nwthepagenum=\@numsubpagenum}
\def\nwopt@alphasubpage{\let\nwthepagenum=\@alphasubpagenum}
\def\nwopt@romansubpage{\let\nwthepagenum=\@romansubpagenum}
\nwopt@alphasubpage

Defines alphasubpage, nosubpage, numsubpage, \nwthepagenum (links are to index).

Used above; previous and next definitions.

* *\subsection{{\tt WEB}-like chunk numbering} We get the effect of WEB-like chunk numbers just by redefining \sublabel to use a counter instead of the current page number. Since the numbers are all distinct, no sub-page number is ever used.

<Labels>+=
\newcount\nw@chunkcount
\nw@chunkcount=\@ne
\def\weblabel#1{%
{%
\let\thepage\relax
\def\protect{\noexpand\noexpand\noexpand}%
\edef\@tempa{%
\write\@auxout{%
\string\newsublabel{#1}{{}{\number\nw@chunkcount}}%
}%
}%
\expandafter
}%
\@tempa
\ifvmode\nobreak\fi
}%
\def\nwopt@webnumbering{%
\let\sublabel=\weblabel
\def\nwpageword{chunk}%
\def\nwpageprep{in}%
}%

Defines \nw@chunkcount, \nwopt@webnumbering, \weblabel (links are to index).

Used above; previous definition.

* % **** Cross Referencing ******************************************************** \section{Cross Referencing between Chunks} At the end of each code chunk, two pieces of cross referencing information are given. Since code chunk definition can be continued in other chunks, an indication of where the definition is continued is given. Other chunks using this chunk are also identified. The other piece of information given is a list of identifiers defined by the chunk, and where they are used, together with a list of identifiers used by this chunk and where they are defined. These useful bits of information are given in a chunk comment', usually printed in a smaller font at the end of each code chunk:

<Cross Referencing of Chunks and Identifiers>=
\def\nwcodecomment#1{%
\penalty\nwcodepenalty
\hskip-\codemargin
\begingroup
\rightskip=0pt plus1in
\interlinepenalty\nwcodepenalty
\small\rm #1\par\penalty\nwcodepenalty
\endgroup
}%
\newif\if@firstnwcodecomment\@firstnwcodecommenttrue
\newcount\nwcodepenalty\nwcodepenalty=1000

Defines \@firstnwcodecommentfalse, \@firstnwcodecommenttrue, \if@firstnwcodecomment, \nwcodecomment, \nwcodecommentsep, \nwcodepenalty (links are to index).

Used above; next definition.

* To handle this, information is written to the label file about chunks and identifiers as they are processed. This information can then be used by a second pass over the source text so that forward references are properly handled. Now we go about building the lists of definitions and uses, for both chunks and identifiers. The macros involved are \nwidentdefs, \nwidentuses for the identifier definition and use, \nwalsodefined for continued chunk definition, and \nwused for chunk use. Each of these takes a {\TeX} list as parameter (see later for definition of a {\TeX} list, or see the {\it {\TeX}-in-Practice} volumes. Let's look next at the work done in the second pass, because this processes the definitions written out in the above macros. It is the macro \nwixadd that does the work here. It takes three parameters, the first of which is a macro that indicates whether we have a definition or use. The second parameter is the identifier itself, and the third parameter is the code chunk label wherein this definition or use appears. Suppose the identifier is {\it example}. We check to see if the name *{\tt nwixl@example} is defined. If it is, then we have already seen this identifier, and this use or definition (as indicated by the marker macro) is appended to the list of use/definitions for the identifier. This list is kept as the replacement text for the macro named as above, that is, {\tt nwixl@example}. If this name is not defined, then it is now, with the replacement text given by {\marker{chunk label}}.

<Cross Referencing of Chunks and Identifiers>+=
% #1 marker
% #2 idlabel
% #3 subpage label
\if\NameDefinedConditional{nwixl@#2}%
\expandafter\nwix@cons\csname nwixl@#2\endcsname{#1{#3}}%
\else
\global\NameDef{nwixl@#2}{#1{#3}}%
\fi
}%

Defines \nwixadd (links are to index).

Used above; previous and next definitions.

* *\subsection{Cross Referencing of Chunks} A simple case is where a code chunk is never referenced by any other chunk in this document. This is taken to be a root chunk. Note that multiple root chunks may be specified, since noweb allows code chunks to be extracted by name to separate files.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwnotused#1{%
\nwcodecomment{Root chunk (not used in this document).}%
}%

Defines \nwnotused (links are to index).

Used above; previous and next definitions.

* Let's take \nwused next. The {\TeX}-list of code chunk labels is passed to the (sub)page listing macro.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwused#1{%
\def\@nwtokens{#1}%
\nwcodecomment{This code is used in \pagesl{\@nwtokens}.}%
}%

Defines \nwused (links are to index).

Used above; previous and next definitions.

* Where a code fragment (such as {\LA\it Cross Referencing of Chunks and Identifiers\RA}) is multiply defined, a pointer(s) to the continuation chunks is given.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwalsodefined#1{%
\def\@nwtokens{#1}%
\nwcodecomment{%
This definition is continued in \pagesl{\@nwtokens}.}%
}%

Defines \nwalsodefined (links are to index).

Used above; previous and next definitions.

* A list of definitions made by this code chunk is printed. Each element in the TeX-list is processed by this macro, which itself prints, for each identifier in the definition list, a list of places where that identifier is used. \nwix@id@uses macro, which

<Cross Referencing of Chunks and Identifiers>+=
\def\nwix@id@uses#1#2{% {ident}{label}
\nwix@usecount{#2}%
\def\@id@uses{\nwix@uses{#2}}%
\ifnum\nwix@counter>0
{%
\nwcodecomment{{\tt #1},
used in chunk\@pagesl{\nwix@uses{#2}}.%
}%
}%
\else
\ifnw@hideunuseddefs
\else
{%
\nwcodecomment{{\tt #1}, never used.}%
}%
\fi
\fi
}%

Defines \nwix@id@uses (links are to index).

Used above; previous and next definitions.

* If definitions are unused, a message to this effect is normally printed. This can be turned off by the option \nwopt@hideunuseddefs.

<Cross Referencing of Chunks and Identifiers>+=
\newif\ifnw@hideunuseddefs\nw@hideunuseddefsfalse
\def\nwopt@hideunuseddefs{\nw@hideunuseddefstrue}


Used above; previous and next definitions.

If we are not interested in the actual definitions, here just total up the number of definitions added by this chunk. The current number of uses is maintained in the global counter \nwix@counter: this is incremented by the number seen in this definition.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwix@totaluses#1{% list of index pairs
{%
\count@=0
\def\\##1{%
\nwix@usecount{\@cdr##1\@nil}
}%
#1
\global\nwix@counter\count@
}%
}%


Used above; previous and next definitions.

*\subsection{Cross Referencing of Identifiers} As identifier definitions are encountered in the marked up source, a macro \nwindexdefn is issued to flag the definition. We add this definition to the database, and cross reference it in this code chunk. All index definitions and uses are associated with a label defined with \sublabel or \nosublabel. Either the label is the \sublabel of the code chunk in which the definition or use appears, or it is a \nosublabel appearing in the middle of a documentation chunk. The macro \nwindexdefn takes three parameters, the first two of which denote the identifier. A distinction is made between the printable name of the identifier, and a possibly sanitized version used as a label. The macro adds this identifier to the list of identifiers defined by the chunk whose label is given as the third parameter. The main purpose of this macro is to write the definitions to the label file: a second pass will then pick up the information for actual printing.

<Cross Referencing of Chunks and Identifiers>+=
% \nwindexdefn{printable name}{identifying label}{label of chunk}
\def\nwindexdefn#1#2#3{%
%\message{\string\nwindexdefn:#1:#2:#3}%
\@auxix{\protect\nwixd}{#2}{#3}%
}%

Defines \nwindexdefn (links are to index).

Used above; previous and next definitions.

* Uses of identifiers are flagged by the macro \nwindexuse, with similar parameters to \nwindexdefn.

<Cross Referencing of Chunks and Identifiers>+=
% \nwindexuse{printable name}{identifying label}{label of chunk}
\def\nwindexuse#1#2#3{%
\@auxix{\protect\nwixu}{#2}{#3}%
}%

Defines \nwindexuse (links are to index).

Used above; previous and next definitions.

* The marker macros \nwixd and \nwixu flag definitions and uses respectively within a list. By setting their definitions, the list may be processed to count definitions or uses, generate various layouts, and so on.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwixd#1{{\bf\subref{#1}}}%
\def\nwixu#1{\subref{#1}}%
\def\@auxix#1#2#3{% {marker}{id label}{subpage label}
%\@bsphack
%\if@filesw
{%
\let\nwixd\relax\let\nwixu\relax
\def\protect{\noexpand\noexpand\noexpand}%
\expandafter
}%
\@tempa
%\if@nobreak
\ifvmode\nobreak\fi
%\fi
%\fi
%\@esphack
}%

Defines \@auxix, \nwindexdefn, \nwindexuse (links are to index).

Used above; previous and next definitions.

* Now for something a little more involved. Identifiers are defined in the source by virtue of the hack of including a \verb.@ %def id1 id2. line. This could be generated by other filters in the noweb pipeline, such as finduses (q.v.). Lines of this form \verb.@ %def id1 id2. get translated by the noweave pipe to macro calls of the form: \begin{verbatim} \nwidentdefs{\\{{do}{do}}\\{{dont}{dont}}} \end{verbatim} and it is this macro which we now define. This macro counts the number of definitions first, and if this is non-zero, prints the list of identifiers using the auxiliary macro \nwix@id@uses.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwidentdefs#1{% list of index pairs
\ifnw@hideunuseddefs\nwix@totaluses{#1}%
\else\nwix@listcount{#1}%
\fi
\ifnum\nwix@counter>0
\nwcodecomment{Defines:}%
{%
\def\\##1{\nwix@id@uses ##1}%
#1
}%
\fi
}%

Defines \nwidentdefs (links are to index).

Used above; previous and next definitions.

* Here we count the number of identifiers in the argument. The list processing template macro \\ is set to count each element of the list.

<Cross Referencing of Chunks and Identifiers>+=
\newcount\nwix@counter
\def\nwix@listcount#1{% #1 is a TeX-list
{%
\count@=0
#1%
\global\nwix@counter=\count@
}%
}%

Defines \nwix@listcount (links are to index).

Used above; previous and next definitions.

count just uses. Flag this by making \nwixu the counting macro \\, and \nwixd null, then calling \nwix@listcount.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwix@usecount#1{%
\let\nwixd=\@gobble \def\nwixu{\\}
\nwix@listcount{\nwix@uses{#1}}%
}%

Defines \nwix@usecount (links are to index).

Used above; previous and next definitions.

count just definitions. Flag this by making \nwixd the counting macro \\, and \nwixu null, then calling \nwix@listcount.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwix@defcount#1{%
\let\nwixd=\relax\let\nwixu=\@gobble
\nwix@listcount{\nwix@defs{#1}}%
}%

Defines \nwix@defcount (links are to index).

Used above; previous and next definitions.

* Macro to process the list of uses, printing out the code chunk locations where used. This macro is called for both identifier and chunk use lists.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwidentuses#1{% list of index pairs
\nwcodecomment{Uses \let\\=\nwix@id@defs\commafy{#1}.}%
}%

Defines \nwidentuses (links are to index).

Used above; previous and next definitions.

nwixs@c and nwixs@i are sorted lists of chunks and identifiers, respectively.

<Cross Referencing of Chunks and Identifiers>+=
\@ifundefined{nwixs@#1}%
{\global\@namedef{nwixs@#1}{\\{#2}}}%
{\expandafter\nwix@cons\csname nwixs@#1\endcsname{\\{#2}}}%
}%


Used above; previous and next definitions.

\subsection{Cross Referencing (identifier cross-reference) support} *\subsubsection{Tracking definitions and uses} All index definitions and uses are associated with a label defined with \sublabel or \nosublabel. Either the label is the \sublabel of the code chunk in which the definition or use appears, or it is a \nosublabel appearing in the middle of a documentation chunk. \subsubsection{New, improved index code} There are two kinds of lists. One kind is a generic list in which elements are preceded by \\. If the elements are index elements, they are {\it{printable identifier}{label}} pairs. The other kind is a list of sub-page labels, in which each element is preceded by either \nwixd or \nwixu. The reference list for an identifier labelled {\it id} is always called \nwixl@{\it id}. Most applications will work with reference lists by applying \\ either to the defs or to the uses.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwix@uses#1{% {label}
\def\nwixu{\\}%
\let\nwixd\@gobble
\@nameuse{nwixl@#1}%
}%
\def\nwix@defs#1{% {label}
\def\nwixd{\\}\let\nwixu\@gobble\@nameuse{nwixl@#1}}
\def\@gobble#1{}%

Defines \nwix@defs, \nwix@uses (links are to index).

Used above; previous and next definitions.

*\subsubsection{Supporting a mini-index at the end of each chunk} When displaying identifiers used, show the identifier and its definitions.

<Cross Referencing of Chunks and Identifiers>+=
\def\@car#1#2\@nil{#1}%
\def\@cdr#1#2\@nil{#2}%
\def\nwix@id@defs#1{% index pair
{%
{\tt \@car#1\@nil}%
\def\\##1{~\subpageref{##1}}\nwix@defs{\@cdr#1\@nil}%
}%
}%

Defines \@car, \@cdr, \nwix@id@defs (links are to index).

Used above; previous and next definitions.

* The definitions section is a bit more complex, because it is omitted if none of the identifiers defined is ever used.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwix@totaluses#1{% list of index pairs
{%
\count@=0
\def\\##1{%
\nwix@usecount{\@cdr##1\@nil}%
}%
#1
\global\nwix@counter\count@
}%
}%

Defines \nwix@totaluses# (links are to index).

Used above; previous and next definitions.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwopt@noidentxref{%
%\let\nwidentdefs\@gobble
%\let\nwidentuses\@gobble
}%

Defines \nwopt@noidentxref (links are to index).

Used above; previous and next definitions.

* *\subsubsection{Support for chunk and identifier indices} The index in the back shows absolutely all the pages.

<Cross Referencing of Chunks and Identifiers>+=
\def\nw@underlinedefs{% {list with \nwixd, \nwixu}
\let\\=\relax\def\nw@comma{, }%
\def\nwixd##1{%
\\\underline{\subpageref{##1}}\let\\\nw@comma
}%
\def\nwixu##1{%
\\\subpageref{##1}\let\\\nw@comma
}%
}%

Defines \nw@underlinedefs (links are to index).

Used above; previous and next definitions.

<Cross Referencing of Chunks and Identifiers>+=
\newcount\@nwpagetemp

Defines \@nwpagetemp (links are to index).

Used above; previous and next definitions.

* The sequence \@pagesl makes a range of pages from a list of labels. \subpages works from a list of {{subpage}{page}}.

<Cross Referencing of Chunks and Identifiers>+=
\newcount\@nwpagecount
\def\@nwfirstpagel#1{% label
\@ifundefined{r@#1}
{<tex warn of undefined reference to #1 and add page ??>}%
{\edef\@tempa{#1}\@tempa}%
}%

Defines \@nwfirstpagel, \@nwpagecount (links are to index).

Used above; previous and next definitions.

<Cross Referencing of Chunks and Identifiers>+=
\def\@nwnextpagel#1{% label
\@ifundefined{r@#1}%
{<tex warn of undefined reference to #1 and add page ??>}
{\edef\@tempa{#1}\@tempa}%
}%

Defines \@nwnextpagel (links are to index).

Used above; previous and next definitions.

<Cross Referencing of Chunks and Identifiers>+=
\def\@pagenumsl#1{% list of labels
% doesn't include word pages', commas, or and'
\gdef\nw@pages{}\@nwpagecount=0
\def\\##1{\@nwfirstpagel{##1}\let\\=\@nwnextpagel}#1%
\def\\{\let\\=~}\nw@pages
}%

Defines \@pagenumsl (links are to index).

Used above; previous and next definitions.

<Cross Referencing of Chunks and Identifiers>+=
\def\subpages#1{% list of {{subpage}{page}}
\gdef\nw@pages{}\@nwpagecount=0
\def\\##1{%
\edef\@tempa{\noexpand\@nwfirstpage##1}%
\@tempa
\def\\####1{%
\edef\@tempa{\noexpand\@nwnextpage####1}%
\@tempa
}%
}%
#1%
\nwpageword
\ifnum\@nwpagecount=1
\else s%
\fi
\space
\commafy{\nw@pages}%
}%

Defines \subpages (links are to index).

Used above; previous and next definitions.

<Cross Referencing of Chunks and Identifiers>+=
}%

Defines \@nwaddrange (links are to index).

Used above; previous and next definitions.

* \nwpageword and \nwpageprep let you change the wording of the cross-reference information.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwpageword{chunk}  % was page
\def\nwpageprep{in}     % was on


Used above; previous and next definitions.

% **** Indexing *********************************************** \section{Indexing} \subsection{Indexing of Chunks} At the end of the code and documentation listings, an index of all chunk definitions can be made. This is invoked by the \nowebchunks macro.

<Chunk Index Construction>=
\def\nowebchunks{%
\@ifundefined{nwixs@c}%
{\@warning{The are no \string\nowebchunks}}%
%\else
{%
\begingroup
\thenowebchunks\@nameuse{nwixs@c}%
\endgroup
}%
}%

Defines \nowebchunks (links are to index).

Used above; next definition.

<Chunk Index Construction>+=
\def\nowebchunks@external{%
{%
\begin{thenowebchunks}\@input{\jobname.nwi}\end{thenowebchunks}%
}%
\@namedef{nw@notdef}{{0}{(never defined)}}%
}%

Defines \nowebchunks@external (links are to index).

Used above; previous and next definitions.

<Chunk Index Construction>+=
\let\@@underline\underline
\def\underline#1{%
\relax
\ifmmode
\@@underline{#1}%
\else
$\@@underline{\hbox{#1}}$%
\relax
\fi
}%

Defines \@@underline, \underline (links are to index).

Used above; previous and next definitions.

* Typeset the chunk index.

<Chunk Index Construction>+=
\def\thenowebchunks{%
\vskip3pt
\parskip=\z@\parindent=-10pt
\def\\##1{\nw@onechunk##1}
}%

Defines \thenowebchunks (links are to index).

Used above; previous and next definitions.

* Typeset a list of chunks, with the definition occurrences underlined.

<Chunk Index Construction>+=
\def\nw@chunkunderlinedefs{% {list of labels with \nwixd, \nwixu}
\let\\=\relax\def\nw@comma{, }%
\def\nwixd##1{%
\\\underline{\subpageref{##1}}%
\let\\\nw@comma
}%
\def\nwixu##1{%
\\\subpageref{##1}%
\let\\\nw@comma
}%
}%

Defines \nw@chunkunderlinedefs (links are to index).

Used above; previous and next definitions.

* Typeset one chunk name and its uses and definitions.

<Chunk Index Construction>+=
\def\nw@onechunk#1#2#3{%
% parameters:
% #1 {name}
% #2 {label of first definition}
% #3 {list with \nwixd, \nwixu}
%\message{Chunking #1:#2}%
\@ifundefined{r@#2}%
{\message{#2' is undefined.}}%
{%
\indent\LA #1~{\nwtagstyle\subpageref{#2}}\RA
%\if@nwlongchunks
{~\nw@chunkunderlinedefs#3}%
%\fi
\par
}%
}%

Defines \nw@onechunk (links are to index).

Used above; previous definition.

<Cross Referencing of Chunks and Identifiers>+=
\newif\if@nwlongchunks
\@nwlongchunksfalse
\let\nwopt@longchunks\@nwlongchunkstrue

Defines \if@nwlongchunks, \@nwlongchunksfalse, \@nwlongchunkstrue (links are to index).

Used above; previous and next definitions.

* *\subsection{Indexing of Identifiers} The macros here generate single lines of index material. Note that if double column output is required, that is handled elsewhere by a general purpose double column output routine. The identifier index is built by a call on the \nowebindex macro. The actual indices are generated by scanning the lists contained in the expansion of the \nwixs@i macro.

<Cross Referencing of Chunks and Identifiers>+=
\def\nowebindex{%
\@ifundefined{nwixs@i}%
{%
\@warning{The \string\nowebindex\space is empty}%
}%
{%
\begingroup\thenowebindex
\@nameuse{nwixs@i}%
\endgroup
}%
}%

Defines \nowebindex (links are to index).

Used above; previous and next definitions.

* \nowebindex in turn invokes \thenowebindex to create the environment.

<Cross Referencing of Chunks and Identifiers>+=
\def\thenowebindex{%
\parindent=-10pt \parskip=\z@
\def\\##1{\nw@indexline##1}%
}%

Defines \thenowebindex (links are to index).

Used above; previous and next definitions.

* Each line of the index is generated by this macro.

<Cross Referencing of Chunks and Identifiers>+=
\def\nw@indexline#1#2{%
{%
\indent {\tt #1}:
\nw@underlinedefs\@nameuse{nwixl@#2}\par
}%
}%

Defines \nw@indexline (links are to index).

Used above; previous and next definitions.

* The information comes from the list nwisx@i. Here's a more efficient version for the external case:

<Cross Referencing of Chunks and Identifiers>+=
\def\nowebindex@external{%
{%
\begin{thenowebindex}%
\@input{\jobname.nwi}%
\end{thenowebindex}
}%
}%

Defines \nowebindex@external (links are to index).

Used above; previous and next definitions.

* That list (nwisx@i) is created by calls to \nwixlogsorted{i}.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwixlogsorted#1#2{% list data
\toks0={#2}%
\ifvmode\nobreak\fi
}%

Defines \nwixlogsorted (links are to index).

Used above; previous and next definitions.

* If an external index is used, we need a .nwi file, \nwixadds is to be ignored, and we use \nwixaddsx.

<Cross Referencing of Chunks and Identifiers>+=
\def\nwopt@externalindex{%
\else
\let\nowebindex=\nowebindex@external
\let\nowebchunks=\nowebchunks@external
\fi
}%

Defines \nwopt@externalindex (links are to index).

Used above; previous definition.

* % **** Support Routines ************************************************ \section{Support Routines} \subsection{List Management Routines} Lists of identifiers, etc., are managed as {\TeX} lists'', wherein as sequence of values $a_0, a_1, \ldots, a_n$ is represented as the text {\\{$a_0$}\\{$a_1$}$\ldots$\{$a_n$}}. Given a list #1, append the new element #2 to it.

<Housekeeping and Support Routines>=
\def\nwix@cons#1#2{% {list}{\marker{element}}
{%
\toks0=\expandafter{#1}%
\def\@tempa{#2}%
\toks2=\expandafter{\@tempa}%
\xdef#1{\the\toks0 \the\toks2 }%
}%
}%

Defines \nwix@cons (links are to index).

Used above; next definition.

\subsubsection{Writing lists with commas and and''} These macros are used to construct lists of things which are separated by commas, except for the last pair of the list, whch are separated by the word and''. You get one of \begin{itemize}\itemskip=0pt \item $a$'' *\item $a$ and $b$'' \item $a$, $\ldots$, $b$, and $c$'' \end{itemize} Each element of the list has the macro \\ (whatever its current definition happens to be) applied to it. The list' is a standard \TeX{} list, namely elements wrapped in \\{} and concatenated together. For example, $a$ and $b$'' is \\{a}\\{b}.

<Housekeeping and Support Routines>+=
\newcount\@commacount
\def\commafy#1{%
\begingroup
\nwix@listcount{#1}%
\@commacount=\nwix@counter
\let\@comma@each=\\%
\ifcase\@commacount
\let\\=\@comma@each
\or
\let\\=\@comma@each
\or
\def\\{\def\\{ and \@comma@each}\@comma@each}%
\else
\def\\{%
\def\\{, %
\ifnum\@commacount=1 and~\fi
\@comma@each
}%
\@comma@each
}%
\fi
#1%
\endgroup
}%

Defines \@commacount, \commafy (links are to index).

Used above; previous and next definitions.

* With \commafy under our belt, it is a simple matter to generate a list of subpage references, as required by chunk cross referencing.

<Housekeeping and Support Routines>+=
\def\pagesl#1{%  list of labels
\let\\=\nwpagel\commafy{#1}%
}%
\def\nwpagel#1{%
\subref{#1}%
}%


Used above; previous and next definitions.

*\subsection{Section, SubSection Headings, etc.} These are macros to support headings and subheadings. They routine which does all the work is \startsection.

<Housekeeping and Support Routines>+=
%               #1     #2      #3          #4         #5     #6
%
%       LEVEL:          depth; e.g. part=0 chapter=1 sectino=2...
%       INDENT:         indentation of heading from left margin
%       STYLE:          style of heading; e.g.\bf
%
\def\startsection#1#2#3#4#5#6{%
\par\vskip#3 plus 2in
\penalty-200\vskip 0pt plus -2in
\noindent{%
\leftskip=#2 \rightskip=0.5true in plus 4em minus 0.5 true in
\hyphenpenalty=9999 \exhyphenpenalty=9999
#5#6\par%
}%
\vskip#4%
{%
\def\code##1{[[}\def\edoc##1{]]}%\message{[#6]}%
}%
\settocparms{#1}%
\def\themodtitle{#6}%
{%
\def\code{\string\code}\def\edoc{\string\edoc}%
\edef\next{%
\noexpand\write\cont{%
\tocskip
\tocline{%
\hskip\tocindent\tocstyle\relax\themodtitle
}%
{%
\noexpand\the\pageno
}%
}%
}%
\next % write to toc
}%
}%

Defines \startsection (links are to index).

Used above; previous and next definitions.

<Housekeeping and Support Routines>+=
\def\settocparms#1{%
\count@=#1
\ifnum\count@<1
\def\tocskip{\vskip3ptplus1in\penalty-100\vskip0ptplus-1in}%
\def\tocstyle{\bf}%
\def\tocindent{0pt}%
\else
\def\tocskip{}%
\def\tocstyle{\rm}%
\edef\tocindent{\the\dimen@}%
\fi
}%

Defines \settocparms (links are to index).

Used above; previous and next definitions.

<Housekeeping and Support Routines>+=
\def\tocline#1#2{%
\line{%
{%
\ignorespaces#1%
}%
\hfil
\hbox to1.5em{\hss#2}%
}%
}%

Defines \tocline (links are to index).

Used above; previous and next definitions.

<Housekeeping and Support Routines>+=
\def\chapter#1{%
\vfil\eject
\startsection{0}{0pt}{6ex}{3ex}{\frtbf\chapcenter}{#1}%
}%

Defines \chapter (links are to index).

Used above; previous and next definitions.

<Housekeeping and Support Routines>+=
\newcount \sectionnumber \sectionnumber=0
\def\section#1{%
\subsectionnumber=0 \subsubsectionnumber=0
\def\sno{\number\sectionnumber}%
\dimen0=\wd0
\def\titleline{\sno\ #1}%
}%

Defines \section (links are to index).

Used above; previous and next definitions.

<Housekeeping and Support Routines>+=
\newcount \subsectionnumber \subsectionnumber=0
\def\subsection#1{%
\def\ssno{\number\sectionnumber.\number\subsectionnumber}%
\dimen0=\wd0
\edef\titleline{\ssno\enspace#1}%
}%

Defines \subsection (links are to index).

Used above; previous and next definitions.

<Housekeeping and Support Routines>+=
\newcount \subsubsectionnumber \subsubsectionnumber=0
\def\subsubsection#1{%
\def\sssno{\number\sectionnumber.\number\subsectionnumber
.\number\subsubsectionnumber }%
\dimen0=\wd0
\edef\titleline{\sssno\enspace#1}%
}%

Defines \subsubsection (links are to index).

Used above; previous and next definitions.

<Housekeeping and Support Routines>+=
\newcount \subsubsubsectionnumber \subsubsubsectionnumber=0
\def\paragraph#1{%
\def\ssssno{\number\sectionnumber.\number\subsectionnumber
.\number\subsubsectionnumber
.\number\subsubsubsectionnumber }%
\dimen0=\wd0
\edef\titleline{\ssssno\enspace#1}%
}%
\let\subsubsubsection=\paragraph

Defines \paragraph, \subsubsubsection (links are to index).

Used above; previous and next definitions.

<Housekeeping and Support Routines>+=
\def\stylehook{}%


Used above; previous and next definitions.

The \today macro generates today's date in the format 11 August 1995.

<Housekeeping and Support Routines>+=
\def\today{%
\number\day\space
\ifcase\month
\or % nothing for \month=0
January\or February\or March\or April\or
May\or June\or July\or August\or
September\or October\or November\or December%
\fi
\space
\number\year
}%

Defines \today (links are to index).

Used above; previous definition.

* % **** Finalization **************************************************** \section{Finalization} Redefine the \bye macro to do all the work. Don't forget that we redefined \bye in the double column macro, so we have to do that one as well.

<Finalizing and Washup>=
\def\bye{%
\closeout\@auxout
\write\cont{}% ensure that the contents file isn't empty
\closeout\cont
\vfil\eject\pageno=-1 % new page causes contents to be really closed
\DSC@bye
}%
\def\topofcontents{%
\vfil\mark{{\bf Contents}}%
}%
\def\botofcontents{}%

Defines \botofcontents, \bye, \topofcontents (links are to index).

Used above; next definition.

* IMHO (AJH), rather than redefining \bye, a better approach is to define a separate macro \nwendprocessing, and put all the windup stuff in here. An explicit call to \nwendprocessing should then be generated by the markup filters. For the moment, I do nothing.

<Finalizing and Washup>+=
\def\nwendprocessing{% finalize anything that needs it.
}%

Used above; previous definition.

% **** Startup Processing **************************************** \section{Startup Processing} Now ready to go, time for centre bounce. First set up cross referencing:

<Startup Processing>=
\catcode\@=11
\newwrite\@auxout
\InputCWithAt{\jobname.lab}%
\catcode\@=11
\immediate\openout\@auxout = \jobname.lab
%\message{**** label processing done}%

\newwrite\cont
\openout\cont=\contentsfile
\write\cont{\string\catcode\string\@=11}% a hack to make contents

Defines \cont, \readcontents (links are to index).

Used above; next definition.

* Finally we make @ other' again.

<Startup Processing>+=
\catcode\@=12


Used above; previous definition.

*\section{Miscellaneous Bits and Pieces not yet Documented} % **** other stuff not yet updated **********************************

<other stuff not yet updated>=
\def\@refpair#1{%
%\message{\string\@refpair:#1}%
\if\NameDefinedConditional{#1}%
\Ref{#1}%
\else
{0}{0}%
<tex warn of undefined reference to #1>
\fi
}%

Defines \@refpair (links are to index).

Used above; next definition.

\subpagepair produces a {subpage}{page} pair.

<other stuff not yet updated>+=
\def\subpagepair#1#2{% produces {subpage}{page}
\@ifundefined{r@#1}%
{{0}{0}}%
{%
\@ifundefined{2on\@pageref{#1}}%
{{0}{\expandafter\expandafter\expandafter
\@cdr\csname #1\endcsname\@nil}}%
{\@nameuse{#1}}%
}%
}%

Defines \subpagepair (links are to index).

Used above; previous and next definitions.

<other stuff not yet updated>+=
%\def\nwoutput#1{%
%    \nwcodecomment{This code is written to file
%                   {\tt \@stripstar#1*\stripped}.}%
%}%
\def\@stripstar#1*#2\stripped{#1}

Used above; previous and next definitions.

<other stuff not yet updated>+=
\def\@pagesl#1{%  list of labels
%\message{\string\@pagesl:\noexpand#1}%
\gdef\nw@pages{}%
\@nwpagecount=0%
\def\\##1{%
\@nwpagelref{##1}%
%\@nwfirstpagel{##1}%
%\let\\=\@nwnextpagel
}%
#1%
\let\\=\relax
%\nwpageword
\ifnum\@nwpagecount=1%
\else s%
\fi
~%
\commafy{\nw@pages}%
}%

Defines \@pagesl, \@stripstar (links are to index).

Used above; previous and next definitions.

<other stuff not yet updated>+=
\def\swap@#1#2{{#2#1}}%
\def\@nwpagelref#1{%
%\message{\string\@nwpagelref:#1}%
\edef\@pagelpageno{\NameUse{r@#1}}%
\edef\@pagelsubpageno{\expandafter\nwthepagenum\@pagelpageno}%
%\message{\string\@nwpagelref:\@pagelsubpageno}%
\LeftAppendElement{\nw@pages}{\@pagelsubpageno}%
%\message{\string\@nwpagelref:\noexpand\nw@pages}%
}%
\def\@nwpagel#1{\subref{#1},}%

Defines \@nwpagel, \@nwpagelref, \swap@ (links are to index).

Used above; previous and next definitions.

<other stuff not yet updated>+=
% scale cmbx10 instead of using cmbx12 because {\LaTeX} does, so fonts exist
\font\twlbf=cmbx10 scaled \magstep1
\font\frtbf=cmbx10 scaled \magstep2
% These fonts don't work with xdvi!


Used above; previous and next definitions.

<other stuff not yet updated>+=
\long\def\@ifundefined#1#2#3{%
\expandafter\ifx\csname#1\endcsname\relax
#2%
\else#3%
\fi}

Defines \@ifundefined (links are to index).

Used above; previous and next definitions.

<other stuff not yet updated>+=
%
% \chapcenter macro to produce nice centered chapter titles
%
\def\chapcenter{\leftskip=0.5 true in plus 4em minus 0.5 true in
\rightskip=\leftskip
\parfillskip=0pt \spaceskip=.3333em \xspaceskip=.5em
\pretolerance=9999 \tolerance=9999
\hyphenpenalty=9999 \exhyphenpenalty=9999}

Defines \chapcenter (links are to index).

Used above; previous and next definitions.

*\let\begindocument=\relax The following code is largely transliterated from the LaTeX stuff.

<other stuff not yet updated>+=
\def\protect{}%
\def\@warning#1{\message{#1}}%


Used above; previous definition.

<tex warn of undefined reference to #1>=
\@warning{Reference #1' on page \the\pageno\space undefined}

Used above (1), below (2).

<tex warn of undefined reference to #1 and add page ??>=
<tex warn of undefined reference to #1>%
\nwix@cons\nw@pages{\\{\bf ??}}%


Used above (1), below (2).

<add range to range list>=
<set \@tempa to page range(s), marked with \\>%
\edef\@tempa{\noexpand\nwix@cons\noexpand\nw@pages{\@tempa}}\@tempa

Used below (1), below (2), below (3).

<set \@tempa to page range(s), marked with \\>=
\ifnum\@nwhipage=\@nwlopage
\edef\@tempa{\noexpand\noexpand\noexpand\\%
{\nwthepagenum{\number\@nwlosub}{\number\@nwlopage}}}%
\else
\ifnum\count@=\@nwlopage % consecutive pages
\edef\@tempa{\noexpand\noexpand\noexpand\\%
{\nwthepagenum{\number\@nwlosub}{\number\@nwlopage}}%
\noexpand\noexpand\noexpand\\%
{\nwthepagenum{\number\@nwhisub}{\number\@nwhipage}}}%
\else <use rules from Chicago style manual>%
\fi
\fi

Used above.

<use rules from Chicago style manual>=
\ifnum\@nwlopage<110 <normal range>\else
\count@=\@nwlopage \divide\count@ by 100 \multiply\count@ by 100
\ifnum\count@=\@nwlopage <normal range>\else
\count@=\@nwlopage \divide\count@ by 100
\@nwpagetemp=\@nwhipage \divide\@nwpagetemp by 100
\ifnum\count@=\@nwpagetemp %  lo--least 2 digits of hi
\multiply\@nwpagetemp by 100
<normal range>%
\else <normal range>%
\fi
\fi
\fi

Used above.

<normal range>=
\edef\@tempa{%
\noexpand\noexpand\noexpand
\\{\number\@nwlopage--\number\@nwhipage}%
}%

Used above.

\vfill\eject \section{Chunks} \sublabel{ref:fred} \nowebchunks \vfill\eject \section{Index} \BeginDoubleColumns \nowebindex \EndDoubleColumns *\vfill\eject \section{To DO} \enumerate \item resolve (reintroduce) distinction between \label and \newlabel, \sublabel and \newsublabel` (see chunk \subpageref{ref:setupcode}). \item Should generate a warning message if labels change, to indicate that {\TeX} should be rerun to get them right. \endenumerate