% \CheckSum{1447}
% \iffalse meta-comment
%
% Copyright 1993, 1994, 1995, 1996 Alan Jeffrey,
% hacked and maintained 1997, 1998 Sebastian Rahtz,
% copyright 1998, 1999, 2000, 2001 the fontinst maintenance team and any 
% individual authors listed elsewhere in this file.  All rights reserved.
% 
% This file is part of the fontinst system version 1.9.
% -----------------------------------------------------
% 
% It may be distributed under the terms of the LaTeX Project Public
% License, as described in lppl.txt in the base LaTeX distribution.
% Either version 1.1 or, at your option, any later version.
% 
%%% From file: fibasics.dtx
%
%<*driver>
\documentclass{ltxdoc}
\title{The \package{fontinst} utility}
\author{Alan Jeffrey\and Sebastian Rahtz\and Ulrik Vieth\and 
  Lars Hellstr\"om}
\usepackage{fisource}
\begin{document}
\maketitle
\DocInput{fibasics.dtx}
\PrintIndex
\end{document}
%</driver>
% \fi
%
% \StopEventually{}
%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% \begin{quote}
%   ``Can't say I've ever been too fond of beginnings, myself. 
%   \emph{Messy} little things. Give me a good ending any time. 
%   You know where you \emph{are} with an ending.''\relax
%   \nobreak\hskip 0pt plus 1fill\penalty0\hskip 2em\relax
%   \vadjust{}\nobreak\hskip 1em plus 1fill\textemdash
%   \ from \emph{The kindly ones} by \textsc{Neil Gaiman} et al.^^A
%   \nobreak\hskip-\parfillskip\vadjust{}
% \end{quote}
%
%
% \section{The first and the last}
% 
% \subsection{Version numbers}
%
% We start by making some default catcode assignments, in case we are 
% using ini\TeX{}.
%    \begin{macrocode}
%<*pkg>
\catcode`\{=1
\catcode`\}=2
\catcode`\#=6
\catcode`\^=7
%</pkg>
%    \end{macrocode}
%
% \begin{macro}{\fontinstversion}
%   If we are running under ini\TeX{} we cannot put the identification
%   stuff any earlier than this.  Note that |\fontinstversion| is not
%   just used for indentification but also in |\needsfontinstversion|.
%    \begin{macrocode}
%<pkg|doc>\def\fontinstversion{1.926}
%    \end{macrocode}
% \end{macro}
%
% If we are running under ini\TeX{} or \texttt{plain}, we have to get
% around the \LaTeX{}-specific |\ProvidesPackage| stuff.
%
%    \begin{macrocode}
%<*pkg>
\ifx\ProvidesPackage\undefined
   \def\NeedsTeXFormat#1{}
   \def\ProvidesPackage#1[#2]{}
\fi
%</pkg>
%    \end{macrocode}
%
% Now we can identify ourselves as usual.
%
%    \begin{macrocode}
%<doc>\NeedsTeXFormat{LaTeX2e}[1995/06/01]
%<doc>\ProvidesPackage{fontdoc}
%<pkg>\ProvidesPackage{fontinst}
%<pkg|doc>[2003/07/10 v\fontinstversion\space
%<doc>  fontinst documentation package]
%<pkg>  fontinst installation package]
%    \end{macrocode}
%
% While we're at version numbers anyway, we might as well define the 
% command for testing them. Note however that the module name is not 
% \Module{pkg} as above, but \Module{pkg2}. Code in the latter module 
% ends up at the very end of \texttt{fontinst.sty}!
% 
% \begin{macro}{\needsfontinstversion}
%   The macro:
%   \begin{quote}
%      |\needsfontinstversion|\marg{number}
%   \end{quote}
%   checks the version number.
%
%    \begin{macrocode}
%<*pkg2>
\def\needsfontinstversion#1{{
   \a_dimen=#1pt
   \b_dimen=\fontinstversion~pt\x_relax
   \ifnum\a_dimen>\b_dimen
      \immediate\write16{}
      \immediate\write16{Warning:~This~file~needs~fontinst~version~#1.}
      \immediate\write16{Warning:~You~are~using~version~
         \fontinstversion.}
      \immediate\write16{Warning:~This~may~cause~errors.}
      \immediate\write16{}
   \fi
}}
%</pkg2>
%    \end{macrocode}
%
%   In \package{fontdoc}, |\needsfontinstversion| is printed out as a 
%   comment.
%   \changes{1.918}{2001/06/19}{Different formatting in encoding 
%     specification files. (LH)}
%    \begin{macrocode}
%<*doc>
\newcommand*\needsfontinstversion[1]{%
   \ifFD@spec@
      \comment{Automatic processing of this document as a data file 
      requires \textsf{fontinst} v\,#1 or higher.}%
   \else
      \Bheading{Needs fontinst v\thinspace#1}%
   \fi
}
%</doc>
%    \end{macrocode}
% \end{macro}
% 
% 
% \subsection{Special catcodes and configuration file}
% 
% \package{fontinst} uses some unusual, but convenient, settings of 
% |\catcode|. |@| and |_| are made letters, |~| is made a space, and 
% space and newline are ignored. Before setting those however, we save 
% the current values of the catcodes, so that they can be restored at 
% the end of \texttt{fontinst.sty}.
%
% \begin{macro}{\normalcc}
% \begin{macro}{\fontinstcc}
%   \multchanges{\cs{fontinstcc}\cs{normalcc}}{1.915}{2000/08/09}^^A
%      {Introduced commands for changing between \package{fontinst} 
%       internal catcodes and normal catcodes, as suggested by 
%       Karsten Tinnefeld. (LH)}
%   The |\fontinstcc| command changes the catcodes of certain characters 
%   to what is used in the \package{fontinst} source and the |\normalcc| 
%   command changes them back; their use is analogous to that of the 
%   |\make|\-|at|\-|letter| and |\make|\-|at|\-|other| commands in 
%   \LaTeX.
%   
%   If, for some reason, you use other ``normal'' catcodes than 
%   \package{fontinst} does by default, you may have to redefine 
%   |\fontinstcc| and |\normalcc|. The easiest way to do this is 
%   probably to use the |\add_to| macro.
%   
%   \multchanges{\cs{spacecatcode}\cs{nlcatcode}\cs{atcatcode}^^A
%      \cs{underscorecatcode}\cs{tildecatcode}}{1.915}{2000/08/09}^^A
%      {Removed since the contents can just as well be stored in 
%       \cs{normalcc}. (LH)}
%    \begin{macrocode}
%<*pkg>
\def\a_macro#1{\catcode\number`#1=\the\catcode`#1 }
\edef\normalcc{%
   \a_macro{\ }\a_macro{\^^M}\a_macro{\@}\a_macro{\_}\a_macro{\~}
}
%    \end{macrocode}
%   The above definition makes the |\normalcc| macro end with a space. 
%   This is deliberate; the space is used to terminate the last number 
%   in the macro.
%   
%    \begin{macrocode}
\def\fontinstcc{%
   \catcode`\ =9%
   \catcode`\^^M=9%
   \catcode`\@=11%
   \catcode`\_=11%
   \catcode`\~=10
}
\fontinstcc
%</pkg>
%    \end{macrocode}
% \end{macro}\end{macro}
% 
% We input the \texttt{fontinst.rc} file, if it exists.\relax
% \changes{1.6}{1997/02/07}{\texttt{fontinst.rc} search order changed 
%    (Thierry Bouche).}\relax
% \SortIndex{fontinst.rc file}{\texttt{fontinst.rc} file}
%
% UV, 06/1998:  What is this \texttt{fontinst.rc} file good for?
% It turns out that you can use it to do |\def\raw_encoding{8y}|
% if you prefer to install your fonts the other way.
%
%    \begin{macrocode}
%<*pkg2>
%<*!misc>
\if_file_exists{fontinst.rc}\then
   \primitiveinput fontinst.rc
\else
   \immediate\write16{No~file~fontinst.rc.}
\fi
%</!misc>
%    \end{macrocode}
% Use a different configuration file for \texttt{finstmsc.sty}.^^A
% \changes{1.905}{1999/06/21}{Different config file for 
%    \texttt{finstmsc.sty}. (LH)}
%    \begin{macrocode}
%<*misc>
\if_file_exists{finstmsc.rc}\then
   \primitiveinput finstmsc.rc
\else
   \immediate\write16{No~file~finstmsc.rc.}
\fi
%</misc>
%    \end{macrocode}
%
% At the end of \texttt{fontinst.sty}, we restore the catcodes we 
% changed. 
% \changes{1.910}{1999/11/01}{Catcodes restored \emph{after} reading 
%    \texttt{.rc} file. (LH\&UV)}
%
%    \begin{macrocode}
\normalcc
%</pkg2>
%    \end{macrocode}
%
%
% \subsection
% {Plain \TeX{} macros from \texttt{fontinst.ini}}
% ^^A \subsection{PlainTeX macros from fontinst.ini}
%
% If we're running in ini\TeX{} we input some definitions taken
% from \texttt{plain}.
%
%    \begin{macrocode}
%<*pkg>
\ifx\@ne\undefined_command
   \input fontinst.ini\relax
\fi
%</pkg>
%    \end{macrocode}
%
%    \begin{macrocode}
%<*ini>
\chardef\active=13

\chardef\@ne=1
\chardef\tw@=2
\chardef\thr@@=3
\chardef\sixt@@n=16
\chardef\@cclv=255
\mathchardef\@cclvi=256
\mathchardef\@m=1000
\mathchardef\@M=10000
\mathchardef\@MM=20000

\count10=22 % allocates \count registers 23, 24, ...
\count11=9 % allocates \dimen registers 10, 11, ...
\count15=9 % allocates \toks registers 10, 11, ...
\count16=-1 % allocates input streams 0, 1, ...
\count17=-1 % allocates output streams 0, 1, ...
\count20=255 % allocates insertions 254, 253, ...
\countdef\insc@unt=20 % the insertion counter
\countdef\allocationnumber=21 % the most recent allocation
\countdef\m@ne=22 \m@ne=-1 % a handy constant
\def\wlog{\immediate\write\m@ne} % write on log file (only)

\countdef\count@=255
\dimendef\dimen@=0

\outer\def\newcount{\alloc@0\count\countdef\insc@unt}
\outer\def\newdimen{\alloc@1\dimen\dimendef\insc@unt}
\outer\def\newtoks{\alloc@5\toks\toksdef\@cclvi}
\outer\def\newread{\alloc@6\read\chardef\sixt@@n}
\outer\def\newwrite{\alloc@7\write\chardef\sixt@@n}

\def\alloc@#1#2#3#4#5{\global\advance\count1#1by\@ne
  \ch@ck#1#4#2% make sure there's still room
  \allocationnumber=\count1#1%
  \global#3#5=\allocationnumber
  \wlog{\string#5=\string#2\the\allocationnumber}}
\outer\def\newinsert#1{\global\advance\insc@unt by\m@ne
  \ch@ck0\insc@unt\count
  \ch@ck1\insc@unt\dimen
  \ch@ck2\insc@unt\skip
  \ch@ck4\insc@unt\box
  \allocationnumber=\insc@unt
  \global\chardef#1=\allocationnumber
  \wlog{\string#1=\string\insert\the\allocationnumber}}
\def\ch@ck#1#2#3{\ifnum\count1#1<#2%
  \else\errmessage{No~room~for~a~new~#3}\fi}

\outer\def\newif#1{\count@\escapechar \escapechar\m@ne
  \expandafter\expandafter\expandafter
   \edef\@if#1{true}{\let\noexpand#1=\noexpand\iftrue}%
  \expandafter\expandafter\expandafter
   \edef\@if#1{false}{\let\noexpand#1=\noexpand\iffalse}%
  \@if#1{false}\escapechar\count@} % the condition starts out false
\def\@if#1#2{\csname\expandafter\if@\string#1#2\endcsname}
{\uccode`1=`i \uccode`2=`f \uppercase{\gdef\if@12{}}} % `if' is required

\newdimen\p@ \p@=1pt % this saves macro space and time
\newdimen\z@ \z@=0pt % can be used both for 0pt and 0

\def\space{~}
\let\bgroup={
\let\egroup=}

\def\loop#1\repeat{\def\body{#1}\iterate}
\def\iterate{\body \let\next\iterate \else\let\next\relax\fi \next}
\let\repeat=\fi % this makes \loop...\if...\repeat skippable

\def\supereject{\par\penalty-\@MM}
\outer\def\bye{\par\vfill\supereject\end}
%</ini>
%    \end{macrocode}
% The two last commands above also need to be defined if we're 
% running under \LaTeX. In that case we need to be careful with |\bye| 
% however, as no |\if|\textellipsis\ can skip over code that explicitly 
% contains that control sequence, if it has been defined as above.
%    \begin{macrocode}
%<*pkg>
\ifx\bye\undefined_command
   \def\supereject{\par\penalty-\@MM}
   \outer\expandafter\def \csname bye\endcsname
     {\par\vfill\supereject\@@end}
\fi
%</pkg>
%    \end{macrocode}
% 
% \changes{1.910}{1999/11/01}{Make \cs{everyjob} code optional, and 
%    simplify it a little. (LH\&UV)}
%    \begin{macrocode}
%<*ini&everyjob>
\everyjob{%
   \if_file_exists{fontinst.rc}\then
      \primitiveinput~fontinst.rc
   \else
      \immediate\write16{No~file~fontinst.rc.}
   \fi
}
%</ini&everyjob>
%    \end{macrocode}
%
% 
% \section{Basic definitions}
% 
% \subsection{Declaring variables and constants}
%
% Some temporary variables:
% 
% \begin{macro}{\a_count}
% \begin{macro}{\b_count}
% \begin{macro}{\c_count}
% \begin{macro}{\d_count}
% \begin{macro}{\e_count}
% \begin{macro}{\f_count}
% \begin{macro}{\g_count}
%    \begin{macrocode}
%<*pkg>
\newcount\a_count
\newcount\b_count
\newcount\c_count
\newcount\d_count
\newcount\e_count
\newcount\f_count
\newcount\g_count
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}\end{macro}\end{macro}\end{macro}
% \end{macro}
% \begin{macro}{\a_dimen}
% \begin{macro}{\b_dimen}
% \begin{macro}{\c_dimen}
% \begin{macro}{\d_dimen}
%    \begin{macrocode}
\newdimen\a_dimen
\newdimen\b_dimen
\newdimen\c_dimen
\newdimen\d_dimen
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}\end{macro}
% \begin{macro}{\a_toks}
% \begin{macro}{\b_toks}
% \begin{macro}{\c_toks}
%    \begin{macrocode}
\newtoks\a_toks
\newtoks\b_toks
\newtoks\c_toks
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}
% 
% \begin{switch}{_a_}
%   \changes{1.901}{1999/03/07}{Temporary switch added. (LH)}
%    \begin{macrocode}
\newif\if_a_
%    \end{macrocode}
% \end{switch}
% 
% \describecsfamily{\meta{letter}_macro}
% Besides these temporary variables that have to be declared, the family 
% of control sequences with names of the form |\|\meta{letter}|_macro|, 
% such as |\a_macro|, |\b_macro|, etc., should be used as ``macro valued'' 
% temporary variables.
% \changes{1.903}{1999/05/13}{Introduced the 
%    \cs{\meta{letter}_macro} temporary variables, 
%    replaced \cs{temp_command}. (LH)}
% 
% \begin{macro}{\out_file}
%   Some global variables:
%    \begin{macrocode}
\newwrite\out_file
%    \end{macrocode}
% \end{macro}
%
% 
% \begin{macro}{\one_thousand}
% \begin{macro}{\five_hundred}
% \begin{macro}{\one_hundred}
% \begin{macro}{\max_mathchardef}
% \begin{macro}{\two_thousand}
%   \changes{1.913}{2000/03/11}{Constant added. (LH)}
% \begin{macro}{\half_point}
%   \changes{1.913}{2000/03/04}{Constant added. (LH)}
%   Some constants:
%    \begin{macrocode}
\mathchardef\one_thousand=1000
\mathchardef\five_hundred=500
\mathchardef\one_hundred=100
\mathchardef\max_mathchardef="7FFF
\mathchardef\two_thousand=2000
\newdimen\half_point    \half_point=0.5pt
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}\end{macro}\end{macro}\end{macro}
%
%
%  \subsection{Trigonometry macros}
%
% Include David Carlisle's trigonometry macros.  First, do some hacks
% to get round all that |\NeedsTeXFormat{LaTeX2e}| stuff that David
% put in :-)  In v\,1.8 these hacks been moved to an earlier place since
% we put in |\ProvidesPackage| ourselves.
% \SortIndex{trig package}{\package{trig} package}
%
%    \begin{macrocode}
\let\@tempdima\a_dimen
\let\@tempdimb\b_dimen
\input trig.sty
%</pkg>
%    \end{macrocode}
%
% 
% \subsection
% {\package{fontdoc}-specific declarations}
% ^^A \subsection{fontdoc-specific declarations}
% 
% As of v\,1.917, \package{fontdoc} has options, so we better start 
% with declaration and processing of these.
% \changes{1.917}{2001/03/31}{Option processing added. (LH)}
% 
% \begin{option}{specification}
% \begin{switch}{FD@spec@}
%   The \texttt{specification} option tells \package{fontdoc} that the 
%   document is an encoding specification rather than a production 
%   file---this changes some minor details in the typesetting. The 
%   state of this option is recorded in the |FD@spec@| switch. 
%    \begin{macrocode}
%<*doc>
\newif\ifFD@spec@
\FD@spec@false
\DeclareOption{specification}{\FD@spec@true}
%    \end{macrocode}
% \end{switch}\end{option}
% 
% \begin{option}{hypertex}
%   \changes{1.918}{2001/06/17}{Option added. (LH)}
% \begin{option}{pdftex}
%   \changes{1.920}{2001/09/24}{Option added. (LH)}
% \begin{macro}{\FD@codepoint}
%   The \texttt{hypertex} and \texttt{pdftex} options tell 
%   \package{fontdoc} to include Hyper\TeX\ |\special|s and pdf\TeX\ 
%   annotations, in every code point number set using |\Unicode| or 
%   |\textunicode|, for links to glyph images on the Unicode 
%   consortium web site. The URLs to use are as follows:
%   \begin{quote}
%     \small
%     To access the reference glyph for any Unicode character, 
%     you can use the new URL syntax like this:
%     \begin{quote}
%       \texttt{http://www.unicode.org/cgi-bin/refglyph?}^^A
%       \meta{XX}\texttt{-}\meta{nnnn}
%     \end{quote}
%     where \meta{XX} is the point size and \meta{nnnn} is the 
%     hexadecimal codepoint. Please note however that only \texttt{24} 
%     is supported as a size parameter at this time. (We are 
%     reserving the possibility of providing other sizes in the 
%     future.) Here is an example of usage for \texttt{U+4E78}:
%     \begin{quote}
%       \texttt{http://www.unicode.org/cgi-bin/refglyph?24-4E78}
%     \end{quote}
%     (This supports up to 6 hex digits, so it can also be used 
%     with the supplementary characters.)
%   \end{quote}
%   
%   \iffalse
%   Documentation for a similar older service:
%   \begin{quotation}
%     \small
%     You may embed references to the glyph images on the Unicode site 
%     in your own web pages. For example, to display a Euro sign 
%     (\texttt{U+20AC}) you can use the following HTML:
%     \begin{quote}
%       |<IMG SRC="http://charts.unicode.org/Glyphs/20/U20AC.gif">|
%     \end{quote}
%     The subdirectory to use within the \texttt{Glyphs/} directory 
%     is the first two hexadecimal digits of the Unicode code point.
%     The set of glyphs available covers all of Unicode 3.0 with the 
%     exception of Han ideographs and Hangul syllables.
%     
%     However, you should only make occasional use of these glyphs. 
%     If there is too much web traffic the Unicode
%     Consortium may be forced to discontinue this service.
%   \end{quotation}
%   \fi
%   Coding this for Hyper\TeX\ is pretty straightforward.
%    \begin{macrocode}
\DeclareOption{hypertex}{
   \providecommand*\FD@codepoint[1]{%
      \uppercase{\edef\@tempa{#1}}%
      \special{html:<a href="%
         http://www.unicode.org/cgi-bin/refglyph?24-\@tempa
         ">%
      }%
      \texttt{U+\@tempa}%
      \special{html:</a>}%
   }%
}
%    \end{macrocode}
%   The pdf\TeX\ implementation is easy too, but there is one 
%   complication: The key primitive is called |\pdfannotlink| in 
%   v\,0.13, but |\pdfstartlink| in v\,0.14. My thanks goes to H\`an 
%   Th\'{\^e} Th\`anh, who helped me sort that out.
%    \begin{macrocode}
\DeclareOption{pdftex}{
   \providecommand*\FD@codepoint[1]{%
      \mbox{%
         \uppercase{\edef\@tempa{#1}}%
         \ifx \pdfstartlink\@undefined
            \pdfannotlink
         \else
            \pdfstartlink
         \fi attr {/Border [0 0 0]} user {%
            /Subtype /Link /A <<%
               /S /URI /URI (%
                  http://www.unicode.org/cgi-bin/refglyph?24-\@tempa
               )%
            >>}%
         \textcolor{blue}{\texttt{U+\@tempa}}%
         \pdfendlink
      }%
   }%
   \AtEndOfPackage{\RequirePackage[pdftex]{color}}%
}
%    \end{macrocode}
%   It would be quite possible to make these links according to some 
%   other standard (e.g.~\LaTeX\-to\-HTML) instead by including a suitable 
%   definition of |\FD@codepoint| in your \texttt{fontdoc.cfg} file. 
%   I could include code for those standards as well if someone sends 
%   it to me.
%   
%   I decided against using commands in the \package{hyperref} or 
%   \package{hyper} packages for this as these packages do so much more 
%   that I don't want. If some day a package providing a basic interface 
%   for making hyperlinks is included in required \LaTeX\ then this 
%   decision should certainly be reconsidered.
% \end{macro}\end{option}\end{option}
% 
% Input a local configuration file, if it exists.
%    \begin{macrocode}
\InputIfFileExists{fontdoc.cfg}{%
   \typeout{*************************************^^J%
            * Local config file fontdoc.cfg used^^J%
            *************************************}%
}{}
%    \end{macrocode}
%    
% Finally process the options.
%    \begin{macrocode}
\ProcessOptions\relax
%    \end{macrocode}
% 
% 
% The \package{amstext} package is required, since the |\text| command 
% is used in formatting some integer expressions.
% \changes{1.916}{2001/01/02}{Requiring the \package{amstext} package 
%    in \package{fontdoc}. (LH)}
%    \begin{macrocode}
\RequirePackage{amstext}
%    \end{macrocode}
% 
% \begin{macro}{\a@count}
% \begin{macro}{\b@count}
%   \changes{1.916}{2001/01/02}{Variable added. (LH)}
% \begin{macro}{\a@dimen}
%   Three private variables:
%    \begin{macrocode}
\newcount\a@count
\newcount\b@count
\newdimen\a@dimen
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}
%
% Some useful macros and constrol structures:
%
%    \begin{macrocode}
\def\x@cs#1#2{\expandafter#1\csname#2\endcsname}
\def\FD@swap@two#1#2{#2#1}
%    \end{macrocode}
%
% \begin{macro}{\Aheading}
%   \changes{1.909}{1999/10/18}{Use \cs{addvspace} to make space 
%      above. (LH)}
%   \changes{1.909}{1999/10/20}{Insert a \cs{penalty} for pagebreaking 
%      after an \cs{Aheading}. (LH)}
%   \changes{1.920}{2001/10/19}{Encouraged page breaks before an 
%      \cs{Aheading}. (LH)}
% \begin{macro}{\Bheading}
%   |\Aheading| and |\Bheading| are used to typeset various headings.
%    \begin{macrocode}
\newcommand\Aheading[1]{%
   \par\pagebreak[1]\addvspace\medskipamount
   \noindent\textbf{#1}\vadjust{\penalty200}\par
}
\newcommand\Bheading[1]{\par\noindent\textbf{#1}}
%    \end{macrocode}
% \end{macro}\end{macro}
%
% Some formating commands and a macro that comes in handy. It used to 
% say |\raggedright| at this point as well, but that functionality has 
% been moved into |\encoding| and |\metrics|.
% 
% \definechange{raggedright}{1.920}{2001/09/16}{The body (between 
%   \cs{metrics} and \cs{endmetrics}, and \cs{encoding} and 
%   \cs{endencoding} respectively) of a \package{fontdoc} document is 
%   now typeset in a \texttt{flushleft} environment. It used to be that 
%   the entire document was typeset this way. (LH)}
% \usechange{raggedright}
% \changes{1.923}{2002/10/26}{Making sure \cs{lineskiplimit} is 
%    positive. (LH)}
% 
%    \begin{macrocode}
\raggedbottom
\ifdim 1sp>\lineskiplimit \lineskiplimit=0.5pt \fi
\newcommand\plain{\texttt{plain}}
%    \end{macrocode}
%
% \begin{macro}{\plainint}
% \begin{macro}{\plaindiv}
% \begin{macro}{\plainmax}
% \begin{macro}{\plainmin}
%   \package{fontdoc} saves away \LaTeX's |\int|, |\div|, |\max|, and 
%   |\min| as |\plainint|, |\plaindiv|, |\plainmax|, and |\plainmin|, 
%   since these control sequences are going to be used for other 
%   purposes.
%    \begin{macrocode}
\let\plainint=\int
\let\plaindiv=\div
\let\plainmax=\max
\let\plainmin=\min
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}\end{macro}
% 
% \begin{macro}{\TypesetList}
%   \changes{1.914}{2000/05/13}{Macro added. (LH)}
% \begin{macro}{\list@item@counter}
%   The |\TypesetList| command typesets the \meta{arg}s in a sequence of 
%   |\do|\marg{arg} macros with separators depending on position in and 
%   length of the sequence. It is loosely based on a description of a 
%   similar command in the \package{amsref} package, but it has fewer 
%   features, and I don't know if there is any similarity between the 
%   implementations.
%   
%   The syntax is
%   \begin{isyntax}
%     |\TypesetList|\marg{left}\marg{onlysep}\marg{nonlastsep}\penalty0
%       \marg{lastsep}\penalty0\marg{right}\penalty0
%       \marg{empty}\penalty0\marg{wrap}\penalty0\marg{list}
%   \end{isyntax}
%   \meta{list} is the actual list of |\do|\marg{arg}s. If that is 
%   empty then \meta{empty} is typeset. Otherwise the typeset text 
%   begins with \meta{left}, ends with \meta{right}, and contains the 
%   formatted forms of every \meta{arg} in the list of |\do|\marg{arg}s. 
%   The formatting here consists of passing the \meta{arg} as the 
%   argument to \meta{wrap}, which is typically a one-argument macro.
%   Between two ``formatted \meta{arg}s'' will \meta{onlysep}, 
%   \meta{nonlastsep}, or \meta{lastsep} be put, depending on the number 
%   of \meta{arg}s in the list and the position in the list. If the list 
%   has length two then \meta{onlysep} will be used for the only separator 
%   needed. If the list has length greater than two then \meta{nonlastsep} 
%   will be used for all separators but the last, and \meta{lastsep} will 
%   be used for the last.
%   
%   All of the arguments of |\TypesetList| must survive being passed 
%   through a |\def|.
%    \begin{macrocode}
\newcount\list@item@counter
\newcommand\TypesetList[8]{%
   \begingroup
      \list@item@counter=\z@
      \def\do##1{\advance\list@item@counter\@ne}%
      #8%
      \ifcase \list@item@counter \or
         \def\do##1{#1#7{##1}}%
      \or
         \def\do##1{%
            \advance\list@item@counter\@ne
            \ifnum \list@item@counter=\@ne #1\else #2\fi
            #7{##1}%
         }%
      \else
         \advance\list@item@counter\m@ne
         \expandafter\def \expandafter\do \expandafter##\expandafter1%
            \expandafter{\expandafter\ifnum \the\list@item@counter
               =\list@item@counter
               #4%
            \else\ifnum \z@=\list@item@counter
               #1%
            \else
               #3%
            \fi\fi
            \advance\list@item@counter\@ne
            #7{##1}%
         }%
      \fi
      \ifnum \z@=\list@item@counter
         #6%
      \else
         \list@item@counter=\z@
         #8%
         #5%
      \fi
   \endgroup
}
%</doc>
%    \end{macrocode}
% \end{macro}\end{macro}
% 
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% 
% 
% \section
% {\TeX{} hackery}
% ^^A \section{TeX hackery}
% \changes{1.902}{1999/05/01}{Moved Section \thesection\space to 
%     \texttt{fibasics.dtx}. (LH)}
% 
% \subsection{Utiltiy macros}
%
% \begin{macro}{\x_cs}
% \begin{macro}{\x_relax}
% \begin{macro}{\g_let}
%    \begin{macrocode}
%<*pkg>
\def\x_cs#1#2{\expandafter#1\csname#2\endcsname}
\let\x_relax=\relax
\def\g_let{\global\let}
%</pkg>
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}
% \changes{1.900}{1999/02/07}{Replaced \cs{relax} by \cs{x_relax}. (LH)}
%
% \begin{macro}{\x@relax}
%    \begin{macrocode}
%<doc>\let\x@relax=\relax
%    \end{macrocode}
% \end{macro}
% 
% \begin{macro}{\empty_command}
% \begin{macro}{\gobble_one}
% \begin{macro}{\gobble_two}
% \begin{macro}{\gobble_three}
% \begin{macro}{\identity_one}
% \begin{macro}{\first_of_two}
% \begin{macro}{\second_of_two}
% \begin{macro}{\swap_two}
%   \changes{1.912}{2000/02/16}{Macro added. (LH)}
% \begin{macro}{\first_of_three}
%   \changes{1.914}{2000/05/30}{Macro added. (LH)}
%    \begin{macrocode}
%<*pkg>
\def\empty_command{}
\def\gobble_one#1{}
\def\gobble_two#1#2{}
\def\gobble_three#1#2#3{}
\def\identity_one#1{#1}
\def\first_of_two#1#2{#1}
\def\second_of_two#1#2{#2}
\def\swap_two#1#2{#2#1}
\def\first_of_three#1#2#3{#1}
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}\end{macro}\end{macro}\end{macro}
% \end{macro}\end{macro}\end{macro}
%
% \begin{macro}{\hash_char}
% \begin{macro}{\percent_char}
% \begin{macro}{\left_brace_char}
% \begin{macro}{\right_brace_char}
%    \begin{macrocode}
\bgroup
   \catcode`\[=1
   \catcode`\]=2
   \catcode`\#=12
   \catcode`\%=12
   \catcode`\{=12
   \catcode`\}=12
   \gdef\hash_char[#]
   \gdef\percent_char[%]
   \gdef\left_brace_char[{]
   \gdef\right_brace_char[}]
\egroup
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}\end{macro}
%
% \begin{macro}{\first_char}
% Return the first character of a string.
%
%    \begin{macrocode}
\def\first_char#1#2={#1}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\add_to}
%   Append one or more tokens to the replacement text of a 
%   parameterless macro.
%    \begin{macrocode}
\def\add_to#1#2{
   \ifx#1\x_relax
      \def#1{#2}
   \else
      \expandafter\def\expandafter#1\expandafter{#1#2}
   \fi
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\prep_to}
%   Prepend one or more tokens to the replacement text of a 
%   parameterless macro. Note that if more than one token is added then 
%   the second parameter must contain an |\expandafter| between every 
%   pair of tokens you actually mean to contribute. Thus if you want 
%   to prepend |abc| to |\next|, you must write
%   \begin{quote}
%     |\prep_to\next{a\expandafter b\expandafter c}|
%   \end{quote}
%   Also note that the second argument must not be empty.
%    \begin{macrocode}
\def\prep_to#1#2{
   \ifx#1\x_relax
      \expandafter\def\expandafter#1\expandafter{\expandafter#2}
   \else
      \expandafter\def\expandafter#1\expandafter{\expandafter#2#1}
   \fi
}
%    \end{macrocode}
% \end{macro}
% 
% \begin{macro}{\never_do}
%   The command |\do|, protected from expansion.
%   
%    \begin{macrocode}
\def\never_do{\noexpand\do}
%</pkg>
%    \end{macrocode}
% \end{macro}
%
% 
% \subsection{Testing for \TeX\ extensions}
% \changes{1.914}{2000/05/13}{Added commands for testing for 
%    \protect\TeX\ extensions. (LH)}
% Some tasks can be done better (and usually with simpler code) if 
% one can assume that certain features in some \TeX\ extensions, such as 
% \eTeX, is available. Unfortunately one cannot generally make this 
% assumption, but it is sometimes possible to provide two implementations 
% of a macro and at runtime choose the one which best utilizes the 
% available features. This subsection defines macros for making these 
% tests.
% 
% There is also a command |\needsTeXextension| which is used like 
% |\needs|\-|fontinst|\-|version|, but which tests the \TeX\ rather than 
% the version of \package{fontinst}. This ought to be of use for ETX files 
% that describe 16 bit encodings,\footnote{At the time of writing, no 
% such ETX files exist that I know of, but \package{fontinst} should 
% not have any problem using them. /LH} as the current implementation 
% of the (V)PL writer in this case requires the underlying \TeX\ to 
% support 16 bit character codes.
% 
% The normal operation of the extension-testing macros is to set the |_a_| 
% switch to true if the requested extension is present, and to leave the 
% switch as it was if it isn't present. This is so that one can easily 
% test for a feature that has been added to several different extensions 
% of \TeX\ simply by doing the tests in sequence. That, however, is what 
% the testing macros do if the switch |_extensions_warning_| is set to 
% false. When it is set to true they instead expand to a short piece of 
% text suitable for inclusion in a warning message about the absence of 
% a needed feature.
% 
% \begin{switch}{_extensions_warning_}
%   This switch controls whether extension-testing macros should 
%   actually do the test (false) or produce a warning (true).
%    \begin{macrocode}
%<*pkg>
\newif\if_extensions_warning_
\_extensions_warning_false
%    \end{macrocode}
% \end{switch}
% 
% 
% \begin{macro}{\eTeX}
%   The |\eTeX| command has the syntax
%   \begin{quote}
%     |\eTeX|\marg{version number}
%   \end{quote}
%   where the \meta{version number} is the complete version number 
%   (version number plus revision) of the \eTeX\ one wishes to test for.
%   
%   The code below is geared towards not letting unnecessary control 
%   sequences get tokenized, as they will then always occupy a position 
%   in \TeX's hash table, but it seems one cannot get around testing 
%   whether |\eTeXversion| is defined, so we start with that and then 
%   do a |\catcode| trick to prevent \TeX\ from seeing |\eTeXrevision|.
%    \begin{macrocode}
\ifx \eTeXversion\undefined_command
   \catcode`\~=14 % 14=comment
\fi
\def\eTeX#1{
   \if_extensions_warning_
      \space/\space e-TeX\space version\space #1
~  \else
~     \ifdim \number\eTeXversion\eTeXrevision\p@ < #1\p@ \else
~        \_a_true
~     \fi
   \fi
}
\catcode`\~=10
%</pkg>
%    \end{macrocode}
%   \begin{macro}{\eTeXlogo}
%     The |\eTeXlogo| command prints the \eTeX\ logo.
%     \changes{1.923}{2002/10/20}{Added kern, to match 
%       \package{ltugboat} definition. (LH)}
%    \begin{macrocode}
%<*doc>
\def\eTeX#1{\do{\eTeXlogo\nolinebreak[3] v\,#1}}
\def\eTeXlogo{\ensuremath{\varepsilon}-\kern-.125em\TeX}
%</doc>
%    \end{macrocode}
% \end{macro}\end{macro}
% 
% 
% \begin{macro}{\pdfTeX}
%   The |\pdfTeX| command has the syntax
%   \begin{quote}
%     |\pdfTeX|\marg{version number}\marg{revision}
%   \end{quote}
%   where the \meta{version number} is the version number as returned 
%   by |\pdftexversion|, i.e., 100 times what it would normally be 
%   printed as, and the \meta{revision} is the revision code as returned 
%   by |\pdftexrevision|. To test for pdf\TeX\ 0.13c or newer, one would 
%   say |\pdfTeX{13}{c}|.
%   
%   The code below uses the same |\catcode| trick as that in |\eTeX|.
%    \begin{macrocode}
%<*pkg>
\ifx \pdftexversion\undefined_command
   \catcode`\~=14 % 14=comment
\fi
%</pkg>
%<*pkg|doc>
\def\pdfTeX#1#2{%
%<pkg>   \if_extensions_warning_
%<pkg>      \space/\space pdfTeX\space version\space 
%<doc>   \do{pdf\TeX\nolinebreak[3] v\,%
      \ifnum #1<100\space
         0.\ifnum #1<10\space 0\fi
      \else
%<pkg>         \expandafter\swap_two \expandafter.
%<doc>         \expandafter\FD@swap@two \expandafter.%
      \fi
      #1#2%
%<doc>   }
%<doc>}
%</pkg|doc>
%<*pkg>
%    \end{macrocode}
%   The above is not ideal, but it will do for now.
%    \begin{macrocode}
~  \else
~     \ifdim #1>\pdftexversion \else
~        \ifnum \expandafter\expandafter \expandafter` 
~                   \expandafter\first_char \pdftexrevision= <
~               \expandafter` \first_char#2=
~        \else \_a_true \fi
~     \fi
   \fi
}
\catcode`\~=10
%    \end{macrocode}
% \end{macro}
% 
% 
% \begin{macro}{\needsTeXextension}
%   The |\needsTeXextension| command has the syntax
%   \begin{quote}
%     |\needsTeXextension|\marg{extension tests}\marg{who}
%   \end{quote}
%   If none of the extension tests set the |_a_| switch to true, then 
%   it prints a warning detailing the extensions tests which failed. 
%   \meta{who} is what should be listed as the originator of this 
%   message; it is typically the name of the file which contains the 
%   |\needsTeXextension| command.
%   
%   An example (assuming that there will be an |\Omega| test as well 
%   some time in the future; I haven't really looked into what that 
%   should look like, so maybe the arguments should be different): The 
%   command
%   \begin{quote}
%     |\needsTeXextension{\eTeX{1.2}\Omega{1.0}}{foobar.etx}|
%   \end{quote}
%   tests if the current \TeX\ is \eTeX\ verision 1.2 (or newer) 
%   \emph{or} Omega version 1.0 (or newer). The implied conjunction 
%   between the tests is always `or'.
%    \begin{macrocode}
\def\needsTeXextension#1#2{
   \_a_false
   #1
   \if_a_ \else
      \_extensions_warning_true
      \edef\a_macro{#1}
      \_extensions_warning_false
      \fontinstwarningnoline{#2}{
         This~file~needs:\messagebreak
         \expandafter\second_of_two\a_macro
         \iffalse
            <no~sufficient~extensions~were~listed!!>\if_false
         \fi
         \messagebreak
         You~are~not~using~any~of~them.~This~is~likely~to~cause~errors
      }
   \fi
}
%</pkg>
%    \end{macrocode}
%    \begin{macrocode}
%<*doc>
\def\needsTeXextension#1#2{%
   \Bheading{Needs 
      \TypesetList{}{ or }{, }{, or }{}{(unspecified)}{\@firstofone}{#1}}%
}
%</doc>
%    \end{macrocode}
% \end{macro}
% 
% 
% 
% \subsection{Writing to output files}
% 
% \changes{1.901}{1999/03/04}{Pooled output file allocation added. (LH)}
% As of v\,1.901, there are two different output file 
% models in \package{fontinst}. One has been along ``forever'' and is 
% for writing output to files which are only open for a short period of 
% time---every \package{fontinst} file command that opens a file in this 
% model must also close it---and it can only be used for one file at at 
% time. The other model offers pooled allocation of output files---as 
% long as there is an unused \TeX\ output stream to open, you may open a 
% new file, and it does not matter if files are not closed in the revese 
% order of that in which they were opened.
% 
% \begin{macro}{\open_out}
%   \changes{1.901}{1999/03/04}
%      {\cs{xdef} instead of \cs{def} on \cs{out_filename}. (LH)}
% \begin{macro}{\close_out}
% \begin{macro}{\out_line}
% \begin{macro}{\out_lline}
%   \changes{1.908}{1999/08/25}{\cs{edef}, to save macro expansions 
%      later. (LH)}
% \begin{macro}{\out_llline}
%   \changes{1.908}{1999/08/25}{\cs{edef} and don't use \cs{out_lline}, 
%      to save macro expansions later. (LH)}
%   These macros implement the classical output file commands.
%    \begin{macrocode}
%<*pkg>
\def\open_out#1{
   \immediate\openout\out_file=#1 \xdef\out_filename{#1}}
\def\close_out#1{
   \immediate\write16{#1~written~on~\out_filename.}
   \immediate\closeout\out_file}
\def\out_line#1{\immediate\write\out_file{#1}}
\edef\out_lline#1{\noexpand\out_line{\space\space\space#1}}
\edef\out_llline#1{
   \noexpand\out_line{\space\space\space\space\space\space#1}
}
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% 
% 
% In the new model, the basic writing command 
% \DescribeMacro{\pout_line}|\pout_line| takes two arguments: a file 
% identifier control sequence and the token sequence to write. Thus its 
% call looks like
% \begin{quote}
%   |\pout_line|\meta{identifier}\marg{text}
% \end{quote}
% The \meta{identifier} is usually a chardef token whose number tells 
% which input stream is used, but if \TeX\ runs out of output streams 
% then it might be defined as a parameterless macro which expands to 
% |\m@ne|. This has the effect of making all output to that ``file'' go 
% to the log file, from which the data might be salvaged.
% 
% The new model operates using the control sequence family 
% \describecsfamily{out_filename-\meta{stream}}^^A
% |\out_filename-|\meta{stream} 
% both for storing the name of the output file and for handling 
% allocation of output streams.
% 
% \begin{macro}{\TeX_terminal}
% \begin{macro}{\closed_stream}
% \begin{macro}{\out_filename-99}
% \begin{macro}{\out_filename--1}
%   Output streams 16 and above always write to \TeX's terminal, and any 
%   output file that gets closed gets its identifier set to 99 so that 
%   any attempts to write to a closed file can be easily spotted. (99 
%   is the character code for |c|.) Output stream --1 is the log file, and 
%   if another output stream cannot be allocated then attempts to write to 
%   the output file will be redirected to the log file.
%    \begin{macrocode}
\def\TeX_terminal{\string\TeX\space terminal}
\chardef\closed_stream=99
\x_cs\let{out_filename-99}=\TeX_terminal
\x_cs\def{out_filename--1}{\jobname.log}
%    \end{macrocode}
% \end{macro} \end{macro} \end{macro} \end{macro}
% 
% \begin{macro}{\allocate_stream}
% \begin{macro}{\ch@ck}
%    \begin{macrocode}
\def\allocate_stream{
   \a_count=\m@ne
   \b_count=\m@ne
   \loop \ifnum \count17>\a_count
%    \end{macrocode}
%   While |\a_count|${}<$ the number of the last allocated output 
%   stream \textellipsis
%    \begin{macrocode}
      \advance \a_count \@ne
      \x_cs\ifx{out_filename-\the\a_count}\TeX_terminal
%    \end{macrocode}
%   If |\out_filename-|\meta{stream}, where \meta{stream} is the value 
%   of |\a_count|, is equal to |\TeX_terminal|, then output stream 
%   |\a_count| is allocated to the pool but is not used for any 
%   currently open file. Thus we've found a stream that can be used.
%    \begin{macrocode}
         \b_count=\a_count
         \a_count=\count17
      \fi
   \repeat
   \ifnum \b_count=\m@ne
%    \end{macrocode}
%   In this case all streams allocated to the pool are currently in use, 
%   so try to allocate a new one.
%    \begin{macrocode}
      \global\advance\count17by\@ne
      \ifnum \count17<\sixt@@n
%    \end{macrocode}
%   Then case: There was another output stream.
%    \begin{macrocode}
         \b_count=\count17
         \global\x_cs\let{out_filename-\the\b_count}\TeX_terminal
         \wlog{\string\write\the\b_count\space allocated~to~the~pool.}
      \else
%    \end{macrocode}
%   Else case: See to that the output stream allocation register holds 
%   at 16.
%    \begin{macrocode}
         \global\count17=\sixt@@n
      \fi
   \fi
}
%    \end{macrocode}
%   By now, if a new stream could be allocated then the number of that 
%   stream is in |\b_count|, and if it couldn't then |\b_count| is --1.
%   
%   All output streams up to and including that whose number is in 
%   |\count17| is checked to see if it is available. Many unsuccessful 
%   |\newwrite|s could therefore mean we have to do quite a lot of 
%   checking. What's more, output stream 99 would incorrectly be 
%   interpreted as being in the pool but not used. To guard against these 
%   (improbable) errors, |\ch@ck| is redefined to stop allocation 
%   |\count| registers at their limit value.
%    \begin{macrocode}
\def\ch@ck#1#2#3{
   \ifnum \count1#1<#2 \else
      \errmessage{No~room~for~a~new~#3}
      \global\count1#1=#2
   \fi
}
%    \end{macrocode}
% \end{macro} \end{macro}
% 
% 
% \begin{macro}{\open_pout}
% \begin{macro}{\close_pout}
%   The syntax for |\open_pout| is
%   \begin{quote}
%     |\open_pout|\meta{identifier}\marg{name}
%   \end{quote}
%   \meta{name} is the name of the output file one wishes to open. 
%   \meta{identifier} is a control sequence which will be redefined 
%   (globally) to act as an identifier of the file.
%    \begin{macrocode}
\def\open_pout#1#2{
   \allocate_stream
   \ifnum \b_count=\m@ne
      \immediate\write\sixt@@n{fontinst~is~out~of~output~streams.^^J
         Output~file~#2~cannot~be~opened.^^J
         Writes~will~be~redirected~to~the~log~file.
      }
      \gdef#1{\m@ne}
   \else
      \immediate\openout\b_count=#2\x_relax
      \x_cs\xdef{out_filename-\the\b_count}{#2}
      \global\chardef#1=\b_count
   \fi
}
%    \end{macrocode}
%   
%   The syntax for |\close_pout| is
%   \begin{quote}
%     |\close_pout|\meta{identifier}\marg{what}
%   \end{quote}
%   \meta{identifier} is the output stream identifier which should have 
%   been defined in an earlier call of |\open_pout|. \meta{what} is a 
%   string which describes what has been written to the output file, 
%   e.g.\ |Metrics| or |Raw~font|. It will be used to write a message on 
%   the terminal.
%    \begin{macrocode}
\def\close_pout#1#2{
   \ifnum #1=\closed_stream
      \errmessage{Output~file~\string#1~(#2)~not~closed,^^J
         since~it~was~not~open}
   \else
      \immediate\write\sixt@@n{#2~written~on~
         \csname out_filename-\the#1\endcsname.}
      \ifnum #1=\m@ne \else
         \immediate\closeout#1
         \global\x_cs\let{out_filename-\the#1}=\TeX_terminal
      \fi
      \global\chardef#1=\closed_stream
   \fi
}
%    \end{macrocode}
% \end{macro} \end{macro}
% 
% 
% \begin{macro}{\pout_line}
%   The syntax for |\pout_line| is
%   \begin{quote}
%     |\pout_line|\meta{identifier}\marg{text}
%   \end{quote}
%   \meta{identifier} is the output stream identifier which should have 
%   been defined in an earlier call to |\open_pout|. \meta{text} is 
%   what will be written to the file.
%    \begin{macrocode}
\def\pout_line#1#2{\immediate\write#1{#2}}
%    \end{macrocode}
%   
% \begin{macro}{\pout_lline}
%   \changes{1.904}{1999/06/15}{Command added. (LH)}
%   \changes{1.908}{1999/08/25}{\cs{edef}, to save macro expansions 
%      later. (LH)}
% \begin{macro}{\pout_llline}
%   \changes{1.904}{1999/06/15}{Command added. (LH)}
%   \changes{1.908}{1999/08/25}{\cs{edef} and don't use \cs{pout_lline}, 
%      to save macro expansions later. (LH)}
%   There relate to |\pout_line| as |\out_lline| and |\out_llline| to 
%   |\out_line|.
%    \begin{macrocode}
\edef\pout_lline#1#2{\noexpand\pout_line#1{\space\space\space#2}}
\edef\pout_llline#1#2{
   \noexpand\pout_line#1{\space\space\space\space\space\space#2}
}
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}
% 
%
% \begin{macro}{\tempfileprefix}
% \begin{macro}{\temp_prefix}
%   Selecting the directory for temporary files.
%
%    \begin{macrocode}
\def\tempfileprefix#1{\def\temp_prefix{#1}}
\tempfileprefix{}
%</pkg>
%    \end{macrocode}
% \end{macro} \end{macro}
%
%
% \subsection{Conditionals}
%
% \subsubsection
% {Conditionals in \package{fontinst}}
% ^^A \subsubsection{Conditionals in fontinst}
% 
% \begin{macro}{\then}
% \begin{macro}{\if_true}
% \begin{macro}{\if_false}
%   In order to write macros that expand out to nested |\if|-statements,
%   I say:
%   \begin{quote}
%      |\ifblah| \textellipsis\ |\then| \textellipsis\ |\else| 
%      \textellipsis\ |\fi|
%   \end{quote}
%   In order to match the |\fi|, |\then| has to be an |\if|.
%   
%    \begin{macrocode}
%<pkg|doc>\let\then=\iffalse
%<*pkg>
\def\if_false{\iffalse}
\def\if_true{\iftrue}
%    \end{macrocode}
% \end{macro} \end{macro} \end{macro}
%
% \begin{macro}{\if_defined}
% \begin{macro}{\if_undefined}
%   \multchanges{\cs{if_defined}\cs{if_undefined}}{1.912}
%      {2000/02/10}{Macro added. (LH)}
%   These two macros are used as
%   \begin{quote}
%     |\if_defined|\marg{control sequence name}|\then|\\
%     |\if_undefined|\marg{control sequence name}|\then|
%   \end{quote}
%   The latter is functionally equivalent to
%   \begin{quote}
%     |\x_cs\ifx|\marg{control sequence name}|\x_relax|
%   \end{quote}
%   but it is shorter (1--3 tokens, depending on whether the 
%   unnecessary braces around \meta{control sequence name} are included 
%   or not). The former tests the same thing, but has true and false 
%   cases reversed.
%   
%   Apart from that it is shorter, another important reason for 
%   introducing these macros is that the \eTeX\ primitives 
%   |\ifcsname| and |\unless| provide a much better implementation than 
%   what is possible in normal \TeX. Therefore it is desirable to use 
%   these commands as much as possible, and by introducing these macros 
%   one can achieve this without having double definitions for more 
%   than these two macros.
%   
%   To avoid trouble with mismatched ifs and tokenizing control 
%   sequences special for \eTeX, |~| is temporarily made a comment 
%   character. I'm not sure |\ifcsname| and |\unless| weren't available 
%   in \eTeX\ versions before 2.0, but that's the oldest version I have 
%   a manual for.
%   \multchanges{\cs{if_defined}\cs{if_undefined}}{1.914}{2000/05/13}
%      {Automatically selecting between \protect\TeX\ and \eTeX\ 
%       definitions. (LH)}
%    \begin{macrocode}
\_a_false\eTeX{2.0}
\if_a_\else \catcode`\~=14\x_relax \fi
%    \end{macrocode}
%    \begin{macrocode}
~  \def\if_defined#1\then{\ifcsname#1\endcsname}
~  \def\if_undefined#1\then{\unless\ifcsname#1\endcsname}
%    \end{macrocode}
%    \begin{macrocode}
\catcode`\~=\if_a_ 14 \else 10 \fi \x_relax
%    \end{macrocode}
%    \begin{macrocode}
~  \def\if_defined#1\then{
~     \expandafter\ifx \csname#1\endcsname\x_relax
~        \expandafter\if_false
~     \else
~        \expandafter\if_true
~     \fi
~  }
~  \def\if_undefined#1\then{
~     \expandafter\ifx \csname#1\endcsname\x_relax
~  }
%    \end{macrocode}
%    \begin{macrocode}
\catcode`\~=10\x_relax
%    \end{macrocode}
% \end{macro}\end{macro}
% 
% \begin{macro}{\gobble_if}
%   It is sometimes best to skip both the then-part and 
%   the else-part of a conditional. |\gobble_if| does this by using the 
%   fact that expanding |\else| skips everything until the next matching 
%   |\fi| without looking for other |\else|s.
%   \changes{1.900}{1998/12/11}{Macro added. (LH)}
%   \changes{1.913}{2000/03/03}{Macro redefined; it now works entirely 
%      in the mouth. (LH)}
%    \begin{macrocode}
\def\gobble_if{\iftrue\else}
%    \end{macrocode}
% \end{macro}
% 
% \begin{macro}{\if_or}
% \begin{macro}{\or_else}
%   |\if_or| \textellipsis\ |\or_else| \textellipsis\ |\then| gives the 
%   disjunction of two booleans.
%    \begin{macrocode}
\def\if_or#1\or_else#2\then{
   #1\then
      \expandafter\if_true
   \else
      #2\then
         \expandafter\expandafter\expandafter\if_true
      \else
         \expandafter\expandafter\expandafter\if_false
      \fi
   \fi
}
%    \end{macrocode}
% \end{macro}\end{macro}
% 
% \begin{macro}{\if_equal}
%   The |\if_equal| macro is a \textellipsis|\then|-style wrapper around the 
%   |\ifx| primitive. Its calling syntax is
%   \begin{quote}
%     |\if_equal|\meta{token1}\meta{token2}|\then|
%   \end{quote}
%   \changes{1.912}{2000/02/23}{Macro added. (LH)}
%    \begin{macrocode}
\def\if_equal#1\then{\ifx#1}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\if_file_exists}
%   |\if_file_exists| checks to see if a file exits, using |\openin|.
%
%    \begin{macrocode}
\def\if_file_exists#1\then{
   \immediate\openin1=#1\x_relax
   \ifeof1\x_relax
      \immediate\closein1
      \expandafter\if_false
   \else
      \immediate\closein1
      \expandafter\if_true
   \fi
}
%</pkg>
%    \end{macrocode}
% \end{macro}
% 
% 
% \subsubsection
% {Conditionals in \package{fontdoc}}
% ^^A \subsubsection{Conditionals in fontdoc}
% 
% \changes{1.909}{1999/10/16}{System for documenting both branches of 
%    \texttt{if} statements in ETX and MTX files added. (LH)}
% In order to get a reasonable documentation of branches in an ETX or 
% MTX file, the code in both branches must be typeset and the positions 
% of the if, the else, and the fi must be clearly marked. There seems to 
% be no reasonable way to achieve this if the standard names for the 
% else and fi are used. Therefore the alternative names |\Else| and 
% |\Fi| for |\else| and |\fi| have been introduced, to be used as in 
% for example
% \begin{quote}
%   |\ifisint{monowidth}\then|\\
%   \vadjust{}\quad\meta{then-part}\\
%   |\Else|\\
%   \vadjust{}\quad\meta{else-part}\\
%   |\Fi|
% \end{quote}
% 
% \begin{macro}{\Else}
% \begin{macro}{\Fi}
%   By default, these are identical to their lowercase counterparts.
%    \begin{macrocode}
%<*pkg|doc>
\let\Else=\else
\let\Fi=\fi
%</pkg|doc>
%    \end{macrocode}
% \end{macro}\end{macro}
% 
% The interesting part begins if the ETX or MTX file gives the command 
% |\showbranches|, since this means (i) that it wants the branches to be 
% shown and (ii) that it complies to a simple rule about where to use 
% |\Else| and |\Fi|. The rule is as follows: If an \texttt{if} statement 
% is of \package{fontinst} form (it uses |\then|), then it must be 
% terminated by |\Fi|, and a possible else in the statement must be an 
% |\Else|. If an \texttt{if} statement is \emph{not} of \package{fontinst} 
% form (it has no |\then|), then it must be terminated by |\fi|, and a 
% possible else in the statement must be an |\else|. Only the 
% \package{fontinst} form \texttt{if} statements are affected by 
% |\showbranches|.
% 
% \begin{macro}{\showbranches}
% \begin{macro}{\generic@if}
%   The |\showbranches| command changes the definitions of 
%   |\generic@if|, |\then|, |\Else|, and |\Fi| so that the branches of 
%   \texttt{if} statements will be made visible. |\generic@if| is used 
%   to implement all the \package{fontinst} form \texttt{if} statements 
%   in \package{fontdoc}. It is called as
%   \begin{quote}
%     |\generic@if|\marg{description}
%   \end{quote}
%   and this will by default expand to |\iftrue|, but after executing 
%   |\showbranches| it will instead typeset
%   \begin{quote}
%     If \meta{description} then
%   \end{quote}
%   and do a bit of additional housekeeping.
%   
%    \begin{macrocode}
%<*doc>
\def\generic@if#1{\iftrue}
%    \end{macrocode}
%    \begin{macrocode}
\newcommand\showbranches{%
   \let\generic@if=\branches@if
   \let\then=\x@relax
   \let\Else=\branches@else
   \let\Fi=\branches@fi
}   
%    \end{macrocode}
% \end{macro}\end{macro}
% 
% \begin{macro}{\saved@slot@number}
%   The |\saved@slot@number| is used for storing the value of 
%   |\slot@number| at the \texttt{if} until the |\Else|. Unlike 
%   |\slot@number|, it is always set locally.
%    \begin{macrocode}
\newcount\saved@slot@number
%    \end{macrocode}
% \end{macro}
% 
% \begin{macro}{\branches@if}
% \begin{macro}{\branches@else}
% \begin{macro}{\branches@fi}
%   \changes{1.916}{2001/01/25}{Commented out test which concatenates 
%      consecutive \cs{Fi}s, since that doesn't work together with the 
%      \texttt{IfBranch} environment. (LH)}
% \begin{macro}{\branches@type}
% \begin{macro}{\branches@par}
%   The macros |\branches@if|, |\branches@else|, and |\branches@fi| 
%   contain the definitions of |\generic@if|, |\Else|, and |\Fi| 
%   respectively that are used when branches are to be shown. Their 
%   basic task is to typeset the texts |If #1 then|, |Else|, and |Fi| in 
%   an appropriate style and with appropriate spacing around. A 
%   complicating matter is however that |\slot@number| must have the 
%   same value at the beginning of the \textit{else} part as at the 
%   beginning of the \textit{then} part. To achieve this, the value of 
%   |\slot@number| is saved in |\saved@slot@number| at the \textit{if} 
%   and copied back at the \textit{else}. To make this work even with 
%   nested \textit{if}s, both the \textit{then} branch and the 
%   \textit{else} branch are enclosed in groups and 
%   |\saved@slot@number| is assigned locally.
%   
%   There are still some formatting issues to solve, however. In some 
%   cases it works best to put the text of adjacent \textit{if}, 
%   \textit{else}, or \textit{fi} in the same paragraph, and it must be 
%   possible to recognize those cases. This is done by looking at the 
%   macro |\branches@type|, which should expand to
%   \begin{enumerate}
%     \item[\texttt{0}] if the preceeding item was an \textit{if},
%     \item[\texttt{1}] if the preceeding item was an \textit{else} 
%        preceeded by an \textit{if},
%     \item[\texttt{2}] if the preceeding item was an \textit{else} 
%        not preceeded by an \textit{if},
%     \item[\texttt{3}] if the preceeding item was a \textit{fi},
%     \item[\texttt{4}] if it was anything else.
%   \end{enumerate}
%   |\branches@par| is used for resetting |\branches@type| to \texttt{4}. 
%   It is an auto-resetting definition of |\par|.
%   
%    \begin{macrocode}
\def\branches@if#1{%
   \ifnum \branches@type=\tw@
      \begin{IfBranchDummy}%
      \textit{ if #1 then}%
   \else
      \par
      \ifFD@tight@\else \addvspace\medskipamount \fi
      \noindent\textit{If #1 then}%
   \fi
   \saved@slot@number=\slot@number
   \gdef\branches@type{0}%
   \let\par=\branches@par
}
%    \end{macrocode}
%    \begin{macrocode}
\def\branches@else{%
   \ifnum \branches@type=\z@
      \textit{ relax else}%
      \gdef\branches@type{1}%
   \else
      \par
      \end{IfBranch}%
      \noindent\textit{Else}%
      \gdef\branches@type{2}%
   \fi
   \global\slot@number=\saved@slot@number
   \let\par=\branches@par
}
%    \end{macrocode}
%    \begin{macrocode}
\def\branches@fi{%
   \ifnum \branches@type=\thr@@
      \expandafter\end \expandafter{\@currenvir}%
      \expandafter\gdef \expandafter\FD@saved@fis 
         \expandafter{\FD@saved@fis \space fi}%
   \else
      \end{IfBranch}%
      \gdef\FD@saved@fis{Fi}%
   \fi
   \gdef\branches@type{3}%
   \let\par=\branches@par
}
%    \end{macrocode}
%    \begin{macrocode}
\gdef\branches@type{4}
%    \end{macrocode}
%    \begin{macrocode}
\def\branches@par{%
   \@restorepar
   \ifnum \branches@type=\thr@@
      \noindent\textit{\FD@saved@fis}\par
   \else
      \begin{IfBranch}%
   \fi
   \gdef\branches@type{4}%
}
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}\end{macro}\end{macro}
% 
% \begin{environment}{IfBranch}
%   \changes{1.916}{2001/01/09}{Environment added. (LH)}
%   \changes{1.920}{2001/09/16}{Removed assignment to \cs{listparindent}. 
%     I don't know why it was there in the first place. (LH)}
% \begin{switch}{FD@tight@}
%   \changes{1.916}{2001/01/09}{Switch added. (LH)}
%   The branches of a conditional that is being shown are put in an 
%   \texttt{IfBranch} environment, to emphasize the branches as logical 
%   units in the file. Depending on the value of the \texttt{FD@tight@} 
%   switch, there are two different ways that the branches can be 
%   distinguished. In the non-tight setting (\texttt{FD@tight@} false), 
%   there is one |\medskip|\-|amount| of vertical space before and after 
%   the branch, but no indentation. In the tight setting (which is used 
%   for \meta{glyph commands} and \meta{slot commands}), there is no 
%   extra vertical space around the branch, instead it is indented by 
%   $1\,\mathrm{em}$.
%    \begin{macrocode}
\newif\ifFD@tight@
\newenvironment{IfBranch}{%
   \list{}{%
      \ifFD@tight@
         \setlength\topsep{\z@skip}%
         \@beginparpenalty=\z@
         \@endparpenalty=\z@
         \setlength\leftmargin{1em}%
      \else
         \setlength\topsep{\medskipamount}%
         \@beginparpenalty=-10%
         \@endparpenalty=\@beginparpenalty
         \setlength\leftmargin{\z@}%
      \fi
      \setlength\partopsep{\z@skip}%
      \setlength\itemsep{\z@skip}%
      \setlength\parsep{\z@ plus\p@}%
      \setlength\rightmargin{\z@}%
      \setlength\itemindent{\z@}%
   }%
   \item[]%
}{\endlist}
%    \end{macrocode}
% \end{switch}\end{environment}
% 
% \begin{environment}{IfBranchDummy}
%   \changes{1.916}{2001/01/25}{Environment added. (LH)}
%   In order to get the nesting right, each |\branches@else| command has 
%   to |\begin| a new environment, but if it is immediately followed by 
%   a |\branches@if| then that environment should not cause an 
%   indentation. In these cases the \texttt{IfBranchDummy} environment 
%   is used instead of \texttt{IfBranch}.
%    \begin{macrocode}
\newenvironment{IfBranchDummy}{}{}
%</doc>
%    \end{macrocode}
% \end{environment}
% 
% 
% \subsubsection{Miscellanea}
% 
% \begin{macro}{\primitiveinput}
%
% If |\@@input| is defined, I'll assume it's the \LaTeX{} version
% of the \TeX{} |\input| primitive.  I need this so that I can say
% |\expandafter\foo\primitiveinput|, which doesn't work with the
% \LaTeX{} version of |\input|.
%
%    \begin{macrocode}
%<*pkg>
\x_cs\ifx{@@input}\x_relax
   \let\primitiveinput=\input
\else
   \let\primitiveinput=\@@input
\fi
%    \end{macrocode}
%  \end{macro}
%
% 
% \DescribeMacro{\process_csep_list}
% The macro
% \begin{quote}
%   |\process_csep_list|\marg{pretext}\meta{comma-sep~list}^^A
%      |,\process_csep_list,|
% \end{quote}
% executes \meta{pretext}\marg{item} for every item in the 
% \meta{comma-sep~list}.
% 
% \begin{macro}{\process_csep_list}
%    \begin{macrocode}
\def\process_csep_list#1#2,{
   \ifx\process_csep_list#2
      \expandafter\gobble_one
   \else
      \expandafter\identity_one
   \fi{
      #1{#2}
      \process_csep_list{#1}
   }
}
%</pkg>
%    \end{macrocode}
% \end{macro}
% 
% 
% \begin{macro}{\print@csep@list}
%   \textit{Use of this macro is now deprecated; use \cs{TypesetList} 
%   instead wherever possible.} The macro call
%   \begin{quote}
%     |\print@csep@list|\marg{format}\marg{list}
%   \end{quote}
%   prints the comma-separated list \meta{list} in math mode. 
%   \meta{format} can be used to set the style in which the list is 
%   printed, since it is executed in the beginning of the same group as 
%   in which the list is printed.
%   
%   The formating is based on changing the |\mathcode| of comma to 
%   |"8000| so that the comma can be used as if it was an active character 
%   without actually having to be one.
%    \begin{macrocode}
%<*doc>
\begingroup
   \catcode`\,=13
   \gdef\print@csep@list#1#2{%
      $%
      \ifnum "8000=\mathcode`\,\else
         \mathchardef\private@comma=\mathcode`\,%
         \mathcode`\,="8000\x@relax
      \fi
      #1%
      \let,=\active@comma
      #2%
      $%
   }
\endgroup
\def\active@comma{\private@comma \penalty\binoppenalty}
%</doc>
%    \end{macrocode}
% \end{macro}
% 
% 
% 
% \subsection{Real numbers}
% 
% \TeX's \meta{number}s are merely integers, but \package{fontinst} 
% needs to store and calculate with numerical entities (most of which 
% are lengths) that are intrinsically real numbers. Most of the time, 
% \package{fontinst} does this by using a representation of real numbers 
% by integers in which a real number $x$ is represented by the integer 
% that $1000x$ gets rounded to. This representation has proved 
% sufficiently precise for most purposes.
% 
% There are however a few cases in which real numbers must be delt with 
% in a more general fashion. Generic routines for this appear in this 
% subsection.
% 
% \begin{macro}{\make_factor}
%   \changes{1.903}{1999/05/13}{Macro added. (LH)}
%   The |\make_factor| macro is meant to be used in the context
%   \begin{quote}
%     |\make_factor|\marg{number}
%   \end{quote}
%   where \meta{number} can be any legal \TeX\ number. It expands to 
%   the same number divided by 1000, with decimals, so that what it 
%   expands to matches the regular expression
%   \begin{quote}
%     |-?[0-9]+\.[0-9][0-9][0-9]|
%   \end{quote}
%   
%   More specifically, |\make_factor| has two tasks to perform: it takes 
%   care of the sign, so that its subsidary macros need only work with 
%   unsigned numbers, and it converts the \meta{number} (which could 
%   well be a countdef or mathchardef token) to a sequence of digits.
%    \begin{macrocode}
%<*pkg>
\def\make_factor#1{
   \ifnum #1<\z@
      -\expandafter\make_factor_i\expandafter{\number-#1}
   \else
      \expandafter\make_factor_i\expandafter{\number#1}
   \fi
}
%    \end{macrocode}
%   
%   \begin{macro}{\make_factor_i}
%     |\make_factor_i| distinguishes between the two main cases of 
%     numbers that in absolute value are less than 1000 and numbers that 
%     in absolute value are greater than or equal to 1000. In the former 
%     case, zeros need to be inserted. In the latter case, some number 
%     of digits need to be stepped over before the decimal point can be 
%     inserted.
%    \begin{macrocode}
\def\make_factor_i#1{
   \ifnum #1<\one_thousand
      \make_factor_ii{#1}
   \else
      \make_factor_iii #1
   \fi
   #1
}
%    \end{macrocode}
%   \end{macro}
%   
%   \begin{macro}{\make_factor_ii}
%     |\make_factor_ii| inserts extra zeros, in the extent it is 
%     needed.
%    \begin{macrocode}
\def\make_factor_ii#1{
   0.
   \ifnum #1<\one_hundred
      0
      \ifnum #1<10~ 0\fi
   \fi
}
%    \end{macrocode}
%   \end{macro}
%   
%   \begin{macro}{\make_factor_iii}
%     |\make_factor_iii| steps over one digit and checks if this is the 
%     correct position for the decimal point. Note that |#2#3| is 
%     exactly the digits in the number that has not been stepped over. 
%     Also note that comparision with |#2#3| would not work, since |#2| 
%     can be |0|.
%    \begin{macrocode}
\def\make_factor_iii#1#2#3\fi#4{
   \fi
   #4
   \ifnum 1#3<\one_thousand
      .
   \else
      \make_factor_iii#2#3
   \fi
}
%    \end{macrocode}
%   \end{macro}
% \end{macro}
% 
% It also happens that real numbers are represented by dimens, in the 
% common way that the number 1 is represented by the dimen 1\,pt. For 
% those cases the following macro is indispensable.
% 
% \begin{macro}{\lose_measure}
%   Get rid of a trailing |pt| when converting dimension.
%    \begin{macrocode}
{
   \catcode`\p=12
   \catcode`\t=12
   \gdef\lose_measure#1pt{#1}
}
%</pkg>
%    \end{macrocode}
% \end{macro}
% 
% 
% \subsection{Error, warning, and info messages}
% 
% The code in this subsection is an adaptation of code from the 
% \LaTeX\ kernel---more precisely from the source file 
% \texttt{lterror.dtx}---and the same is true for some of the comments. 
% As authors of that code are listed Johannes Braams, David Carlisle, 
% Alan Jeffrey, Leslie Lamport, Frank Mittelbach, Chris Rowley, and 
% Rainer Sch\"opf. The original source can be found in the file 
% \texttt{lterror.dtx} in the \texttt{macros}\slash\texttt{latex}\slash
% \texttt{base} directory in any of the Comprehensive \TeX\ Archive 
% Network FTP sites.\footnote{As if anyone who has managed to get this 
% far didn't already know that!}
% 
% That should have fulfilled the conditions in the LPPL.^^A
% \changes{1.906}{1999/07/23}{Adaptation of \LaTeX's message system 
%    completed. (LH)}
% \par\bigskip
% 
% 
% \subsubsection{General commands}
%
% \begin{macro}{\messagebreak}
%   This command prints a new-line inside a message, followed by a 
%   continuation whose exact appearence may depend on the context. 
%   Normally this command is defined to be |\relax|, but inside messages 
%   it gets redefined to a linebreak (|^^J|) followed by the appropriate 
%   continuation.
%   \changes{1.909}{1999/10/16}{New name for \cs{message_break}. (LH)}
%    \begin{macrocode}
%<pkg>\let\messagebreak\x_relax
%<doc>\let\messagebreak\space
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\generic_info}
%    This takes two arguments: a continuation and a message, and sends 
%    the result to the log file.
%    \begin{macrocode}
%<*pkg>
\def\generic_info#1#2{
   \begingroup
      \def\messagebreak{^^J#1}
      \immediate\write\m@ne{#2\on_line.}
   \endgroup
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\generic_warning}
%    This takes two arguments: a continuation and a message, and sends 
%    the result to the screen.
%    \begin{macrocode}
\def\generic_warning#1#2{
   \begingroup
      \def\messagebreak{^^J#1}
      \immediate\write\closed_stream{^^J#2\on_line.^^J}
   \endgroup
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\generic_error}
%   ``This macro takes four arguments: a continuation,
%   an error message, where to go for further information, and the help
%   information.  It displays the error message, and sets the error help
%   (the result of typing |h| to the prompt), and does a horrible hack
%   to turn the last context line (which by default is the only context
%   line) into just three dots.  This could be made more efficient.''
%   
%   Thus far the \LaTeX\ comments, but the horrible hack it mensions 
%   has been removed since it just makes things look strange when 
%   |\errorcontextlines| is larger than one.
% ^^A What the hack actually does is that it turns 
% ^^A as much as possible of the topmost context line to spaces. It has 
% ^^A two ways of achieving this. The first is to make the context line 
% ^^A too long to display in full, by ending the argument of |\errmessage| 
% ^^A with the control sequence
% ^^A \begin{quote}
% ^^A   \tiny\verb*+\@err@                          +^^A
% ^^A   \verb*+                                       +
% ^^A \end{quote}
% ^^A As its name ends with a long sequence of spaces, it won't be visible; 
% ^^A the |@err@| appears in the |...| part of the line. The other method 
% ^^A it uses is to turn every token in the context line that is not part 
% ^^A of a control sequence name to spaces (as characters, not in 
% ^^A category) through a |\lowercase| trick. The only characters that 
% ^^A cannot be turned into spaces this way are the three continuation 
% ^^A dots.
%   The ``where to go for further information'' message is currently not 
%   used (it is commented out in |\fontinsterror| below), since there 
%   is no good place to refer to anyway. If the documentation is ever 
%   improved in this respect, it would of course be best to reinsert 
%   this message. Note however that unlike the case in \LaTeX, this 
%   message should end with a |^^J|.
%   
%   A complication is that \TeX\ versions older than 3.141 have a bug 
%   which causes |^^J| to not force a linebreak in |\message| and 
%   |\errmessage| commands. So for these old \TeX's we use a |\write| to 
%   produce the message, and then have an empty |\errmessage| command. 
%   This causes an extra line of the form
%\begin{verbatim}
%! .
%\end{verbatim}
%   to appear on the terminal, but if you do not like it, you can always
%   upgrade your \TeX!
%   
%   Since I don't think many \package{fontinst} users use such old 
%   \TeX s, I removed \LaTeX's test for \TeX\ version at this point. The 
%   code for old \TeX s is still there, but it lies in a \package{docstrip} 
%   module of its own.
%   
%   First the `standard case'.
%    \begin{macrocode}
%<*!oldTeX>
\def\generic_error#1#2#3#4{
   \begingroup
      \immediate\write\closed_stream{}
      \def\messagebreak{^^J}
      \edef\a_macro{{#4}}
      \errhelp\a_macro
      \def\messagebreak{^^J#1}
      \errmessage{#2.^^J^^J#3
         Type~\space H~<return>~\space for~immediate~help
      }
   \endgroup
}
%</!oldTeX>
%    \end{macrocode}
%
% Secondly the version for old \TeX's.
%    \begin{macrocode}
%<*oldTeX>
\def\generic_error#1#2#3#4{%
   \begingroup
      \immediate\write\closed_stream{}
      \def\messagebreak{^^J}
      \edef\a_macro{{#4}}
      \errhelp\a_macro
      \def\messagebreak{^^J#1}
      \immediate\write\closed_stream{!~#2.^^J^^J#3^^J
         Type~\space H~<return>~\space for~immediate~help.
      }
      \errmessage{}
   \endgroup
}
%</oldTeX>
%    \end{macrocode}
% \end{macro}
% 
% 
% 
% \begin{macro}{\fontinsterror}
%   \changes{1.909}{1999/10/16}{New name for \cs{fontinst_error}. (LH)}
% \begin{macro}{\fontinstwarning}
%   \changes{1.909}{1999/10/16}{New name for \cs{fontinst_warning}. (LH)}
% \begin{macro}{\fontinstwarningnoline}
%   \changes{1.909}{1999/10/16}{New name for 
%       \cs{fontinst_warning_no_line}. (LH)}
% \begin{macro}{\fontinstinfo}
%   \changes{1.909}{1999/10/16}{New name for \cs{fontinst_info}. (LH)}
%   These commands are intended for giving a uniformed, and for the 
%   programmers hopefully simplified, form of error, warning, and info 
%   messages. The syntax is:
%   \begin{quote}
%     |\fontinsterror|\marg{subsystem}\marg{error}\marg{help}\\
%     |\fontinstwarning|\marg{subsystem}\marg{warning}\\
%     |\fontinstwarningnoline|\marg{subsystem}\marg{warning}\\
%     |\fontinstinfo|\marg{subsystem}\marg{info}
%   \end{quote}
%   A \meta{subsystem} in this context is intended to be some piece of 
%   text which identifies some functionally clearly defined part of 
%   \package{fontinst}. Examples of \meta{subsystem}s could be 
%   \texttt{PL to MTX converter}, \texttt{Ligful (V)PL writer}, and 
%   \texttt{Latin family}.
%   
%   The |\fontinsterror| command prints the \meta{error} message, and 
%   presents the interactive prompt; if the user types |h|, then the 
%   \meta{help} information is displayed. The |\fontinstwarning| 
%   command produces a warning but does not present the interactive 
%   prompt. The |\fontinstwarningnoline| command does the same, but 
%   doesn't print the input line number. The |\fontinstinfo| command 
%   writes the message to the |log| file. Within the messages, the 
%   command |\messagebreak| can be used to break a line and |\space| is 
%   a space, for example:
% \begin{verbatim}
%    \def\foo{FOO}
%    \fontinstwarning{Hungarian}{
%       Your~hovercraft~is~full~of~eels,\messagebreak
%       and~\string\foo\space is~\foo}
% \end{verbatim}
%    produces:
% \begin{verbatim}
%    Hungarian warning:
%            Your hovercraft is full of eels,
%            and \foo is FOO on input line 54.
% \end{verbatim}
% 
%    \begin{macrocode}
\def\fontinsterror#1#2#3{
   \generic_error{
      \four_spaces\four_spaces
   }{
      #1~error:\messagebreak #2
   }{
%       See~the~#1~package~documentation~for~explanation.^^J
   }{#3}
}
%    \end{macrocode}
%    \begin{macrocode}
\def\fontinstwarning#1#2{
   \generic_warning{
      \four_spaces\four_spaces
   }{
      #1~warning:\messagebreak #2
   }
}
%    \end{macrocode}
%    \begin{macrocode}
\def\fontinstwarningnoline#1#2{
   \fontinstwarning{#1}{#2\gobble_one}
}
%    \end{macrocode}
%    \begin{macrocode}
\def\fontinstinfo#1#2{
   \generic_info{
      \four_spaces\four_spaces
   }{
      #1~info:\messagebreak #2
   }
}
%</pkg>
%    \end{macrocode}
%    \begin{macrocode}
%<*doc>
\def\fontinsterror#1#2#3{%
   \Bheading{Error} observed by #1:%
   \begin{quote}#2.\end{quote}%
}
%    \end{macrocode}
%    \begin{macrocode}
\def\fontinstwarning#1#2{
   \Bheading{Warning} from #1:%
   \begin{quote}#2.\end{quote}%
}
%    \end{macrocode}
%    \begin{macrocode}
\let\fontinstwarningnoline=\fontinstwarning
%    \end{macrocode}
%    \begin{macrocode}
\def\fontinstinfo#1#2{
   \Bheading{Info} from #1:%
   \begin{quote}#2.\end{quote}%
}
%</doc>
%    \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\on_line}
%   The message ` on input line~$n$'. \LaTeX\ has special code for 
%   \TeX~2, but since \package{fontinst} has assumed the existence of 
%   the |\errorcontextlines| parameter since v\,1.500, the removal of 
%   that code shouldn't cause problems for anyone who wasn't already 
%   having related problems.
%   
%    \begin{macrocode}
%<*pkg>
\def\on_line{~on~input~line~\the\inputlineno}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\four_spaces}
%   Four spaces. Using |\edef| (rather than |\def| as in \LaTeX) to 
%   save some macro expansions.
%    \begin{macrocode}
\edef\four_spaces{\space\space\space\space}
%    \end{macrocode}
% \end{macro}
% 
%
% \subsubsection{Specific errors}
%
% \begin{macro}{\error_help_a}
% \begin{macro}{\error_help_c}
% \begin{macro}{\error_help_d}
% \begin{macro}{\error_help_e}
%   \changes{1.912}{2000/02/12}{Macro added. (LH)}
%   The more common error help messages. The first three are called 
%   |\@eha|, |\@ehc|, and |\@ehd| in \LaTeX. |\@ehb| is of no use for 
%   \package{fontinst}, so it has been omitted. |\error_help_e| is a 
%   new one for \package{fontinst}.
%    \begin{macrocode}
\gdef\error_help_a{
  Your~command~was~ignored.\messagebreak
  Type~\space I~<command>~<return>~\space to~replace~it~
  with~another~command,\messagebreak
  or~\space <return>~\space to~continue~without~it.}
\gdef\error_help_c{
  Try~typing~\space <return>~
  \space to~proceed.\messagebreak
  If~that~doesn't~work,~type~\space X~<return>~\space to~quit.}
\gdef\error_help_d{
  You're~in~trouble~here.~\space\error_help_c}
\def\error_help_e#1{You~can~continue,~but~the~#1~wrong.}
%    \end{macrocode}
% \end{macro}\end{macro}\end{macro}\end{macro}
%
% 
% \subsubsection{\TeX\ parameters}
% 
% \multchanges{\cs{newlinechar}\cs{errorcontextlines}}{1.914}
%    {2000/05/20}{Moved to error message subsection. (LH)}
% \begin{macro}{\newlinechar}
%   Set |\newlinechar| for |\errhelp| messages.
%    \begin{macrocode}
\newlinechar=`\^^J
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\errorcontextlines}
%   By default, show as much error info as you can.
%   (We assume \package{fontinst} users are \TeX{}perts.)
%    \begin{macrocode}
\errorcontextlines=999
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\tracinglostchars}
%   \changes{1.915}{2000/07/31}{Added setting this parameter. (LH)}
%   Make |\tracinglostchars| positive---this will simplify catching 
%   bugs, as many \package{fontinst} bugs show up in that output is 
%   being generated, but that used to disappear silently when 
%   \package{fontinst} was run under Ini\TeX.
%    \begin{macrocode}
\tracinglostchars=1
%</pkg>
%    \end{macrocode}
% \end{macro}
% 
% \Finale
\endinput