https://github.com/latex3/latex2e
Tip revision: 677a0faec3ada45402c67ba34d9a34e3dd9d5479 authored by Joseph Wright on 30 November 2022, 21:06:22 UTC
Step release tag
Step release tag
Tip revision: 677a0fa
ltfssbas.dtx
% \iffalse meta-comment
%
% Copyright (C) 1993-2022
% The LaTeX Project and any individual authors listed elsewhere
% in this file.
%
% This file is part of the LaTeX base system.
% -------------------------------------------
%
% It may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.3c
% of this license or (at your option) any later version.
% The latest version of this license is in
% https://www.latex-project.org/lppl.txt
% and version 1.3c or later is part of all distributions of LaTeX
% version 2008 or later.
%
% This file has the LPPL maintenance status "maintained".
%
% The list of all files belonging to the LaTeX base distribution is
% given in the file `manifest.txt'. See also `legal.txt' for additional
% information.
%
% The list of derived (unpacked) files belonging to the distribution
% and covered by LPPL is defined by the unpacking scripts (with
% extension .ins) which are part of the distribution.
%
% \fi
% \iffalse
%%% From File: ltfssbas.dtx
%% Copyright (C) 1989-2002 Frank Mittelbach and Rainer Sch\"opf
%
%<*driver>
% \fi
%
%
\ProvidesFile{ltfssbas.dtx}
[2022/07/04 v3.2k LaTeX Kernel (NFSS Basic Macros)]
% \iffalse
\documentclass{ltxdoc}
\begin{document}
\DocInput{ltfssbas.dtx}
\end{document}
%</driver>
% \fi
%
% \iffalse
%<+checkmem>\def\CHECKMEM{\tracingstats=2
%<+checkmem> \newlinechar=`\^^J
%<+checkmem> \message{^^JMemory usage: \filename}\shipout\hbox{}}
%<+checkmem>\CHECKMEM
% \fi
%
%
%
% \GetFileInfo{ltfssbas.dtx}
% \title{A new font selection scheme for \TeX{} macro packages\\
% (Basic Macros)\thanks
% {This file has version number
% \fileversion\ dated \filedate}}
%
% \author{Frank Mittelbach \and Rainer Sch\"opf}
%
% \MaintainedByLaTeXTeam{latex}
% \maketitle
%
% This file contains the main implementation of the `low level' font
% selection commands. See other parts of the \LaTeX\
% distribution, or \emph{The \LaTeX\ Companion} for higher level
% documentation of the \LaTeX\ `New' Font Selection Scheme.
%
% \begin{quote}
% \textbf{Warning:}
% The macro documentation is still basically the documentation from the
% first NFSS release and therefore in some cases probably not
% completely accurate.
% \end{quote}
%
% \MaybeStop{}
%
% \changes{v3.0v}{1998/08/17}{(RmS) Documentation fixes.}
% \changes{v3.0j}{1995/10/22}{(RmS) New size function macro
% \cs{genb@sfcnt} needs to be disabled at \cs{document}.}
% \changes{v3.0i}{1995/10/20}
% {(DPC) Modify autoload code, change \cs{undefined}}
% \changes{v3.0g}{1995/10/04}{Modify autoload code}
% \changes{v3.0f}{1995/08/24}{Added autoload code}
% \changes{v3.0d}{1995/07/13}
% {minor documentation changes}
% \changes{v3.0c}{1995/06/15}
% {(DPC) minor documentation changes}
% \changes{v3.0a}{1995/05/24}
% {(DPC) Make file from previous file, fam.dtx 1995/05/20 v2.2d}
%
%
% \changes{v2.1x}{1994/11/18}{(DPC) use \cs{reserved@f} not \cs{next}}
% \changes{v2.1q}{1994/05/20}{Use new error commands}
% \changes{v2.1o}{1994/05/15}{encoding cmds changed to {enc}-cmd}
% \changes{v2.1k}{1994/05/13}{Remove File identification `typeout'}
% \changes{v2.1j}{1994/05/12}{New baselinestretch concept}
% \changes{v2.1j}{1994/05/12}{Replaced hand-protected commands by
% \cs{DeclareRobustCommand} defs}
% \changes{v2.1h}{1994/04/11}{Added \cs{defaultscriptratio} and
% \cs{defaultscriptscriptratio}. ASAJ.}
% \changes{v2.1g}{1994/03/13}{add 2ekernel module to omit repeated code}
% \changes{v2.1a}{1994/01/17}{New math font setup}
% \changes{v2.0c}{1993/03/18}{Changed all \cs{@tempdima} in
% \cs{@tempdimb} to avoid killing \cs{numberline}}
% \changes{v1.91a}{1992/09/22}{Introduced \cs{tf@size} for math size.}
% \changes{v1.3a}{1991/11/27}{All \cs{family}, \cs{shape} etc.
% renamed to \cs{fontfamily} etc.}
% \changes{v1.2i}{1990/04/01}{Code added from tracefnt.dtx.}
% \changes{v1.2i}{1990/04/01}{Support for TeX3.}
% \changes{v1.2g}{1990/02/16}{Support for changes of \cs{baselineskip}
% without changing the size.}
%
% \changes{v1.2c}{1990/01/23}{\cs{no@version@warning} renamed to
% \cs{no@alphabet@error}.}
% \changes{v1.0s}{1989/11/25}{All \cs{edef}\cs{font@name} changed to
% \cs{xdef}\cs{font@name}.
% Necessary after introduction of
% \cs{begingroup}/\cs{endgroup} in v1.0q.}
% \changes{v1.0s}{1989/11/25}{extra// $\to$ + in \cs{extra@def}.}
% \changes{v1.0o}{1989/11/08}{First parameter of
% \cs{define@mathalphabet}
% and \cs{define@mathgroup} changed
% from string to control sequence.}
% \changes{v1.0m}{1989/09/14}
% {Global replacement: \cs{group} to \cs{mathgroup}}
% \changes{v1.0k}{1989/05/22}{Lines longer than 72 characters folded.}
% \changes{v1.0j}{1989/05/01}{Default for \cs{baselinestretch} added.}
% \changes{v1.0i}{1989/04/29}
% {Removed the \cs{halign} \cs{noalign} correction
% (wasn't bugfree)}
% \changes{v1.0h}{1989/04/29}{Documented problem with \cs{halign}, and
% \cs{noalign}}
% \changes{v1.0g}{1989/04/27}{Documentation revised.}
% \changes{v1.0f}{1989/04/23}{\% in \cs{getanddefinefonts} added.}
% \changes{v1.0e}{1989/04/21}{Documentation is fun!!
% Parameters of \cs{define@mathalphabet} changed.}
% \changes{v1.0d}{1989/04/19}{Even more doc.}
% \changes{v1.0c}{1989/04/14}{More documentation added.}
% \changes{v1.0b}{1989/04/10}{\cs{preload@sizes} added.}
% \changes{v1.0b}{1989/04/10}{\cs{wrong@fontshape} changed to define
% substitution font/shape macro.}
% \changes{v1.0a}{1989/04/10}{Starting with version numbers!!
% \cs{ifmmode} added in \cs{math@group}}
% \changes{v2.1w}{1994/11/17}{\cs{@tempa} to \cs{reserved@a}}
% \changes{v3.0z}{2015/02/21}{Removed autoload code}
% \changes{v3.2d}{2019/08/27}{Make various commands robust}
%
%
%
%
% \section{Preliminary macros}
%
% We define a number
% of macros that will be used later.
%
%
% \begin{macro}{\@nomath}
% |\@nomath| is used by most macros that will have no effect
% in math mode. It issues a warning message.
% \begin{macrocode}
%<*2ekernel>
\def\@nomath#1{\relax\ifmmode
\@font@warning{Command \noexpand#1invalid in math mode}\fi}
% \end{macrocode}
% \end{macro}
%
% \changes{v1.2c}{1990/01/23}{Macro \cs{no@alphabet@help} added}
% \changes{v2.1i}{1994/04/18}{Macro \cs{no@alphabet@help}
% removed again}
%
% \begin{macro}{\no@alphabet@error}
% \changes{v1.2c}{1990/01/23}{Changed to error call}
% \changes{v2.1i}{1994/04/18}{Use std LaTeX error macro}
% The macro |\no@alphabet@error| is called whenever
% the user requests a math \emph{alphabet} that is not
% available in the current \emph{version}.
% In math mode an error message is produced otherwise the command
% keeps silent.
% The argument is the name of the control sequence that identifies
% the math \emph{alphabet}.
% The |\relax| at the beginning is necessary to prevent
% \TeX{} from scanning too far in certain situations.
% \begin{macrocode}
\gdef\no@alphabet@error#1{\relax \ifmmode
\@latex@error{Math\space alphabet\space identifier\space
\noexpand#1is\space undefined\space in\space math\space
version\space `\math@version'}%
{Your\space requested\space math\space alphabet\space
is\space undefined\space in\space the\space current\space
math\space version.^^JCheck\space the\space spelling\space
or\space use\space the\space \noexpand\SetMathAlphabet\space
command.}
\fi}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\new@mathgroup}
% \begin{macro}{\mathgroup}
% We also give a new name to |\newfam| and |\fam|
% to avoid verbal confusion
% (see the introduction).\footnote{For the same reason
% it seems advisable to
% {\ttfamily\bslash let\bslash fam} and
% {\ttfamily\bslash newfam}
% equal to {\ttfamily\bslash relax},
% but this is commented out to retain
% compatibility to existing style files.}
% \changes{v1.2e}{1990/01/28}{\cs{newfam} let to \cs{new@mathgroup}.}
% \changes{v3.0a}{1995/05/24}
% {(DPC) No need to redefine \cs{newfam} as not outer}
% \changes{v3.0b}{1995/05/27}
% {(FMi) But a need to define \cs{new@mathgroup}}
% \changes{v3.0y}{2014/12/30}
% {move allocation to ltplain.}
% \begin{macrocode}
%\def\new@mathgroup{\alloc@8\mathgroup\chardef\sixt@@n}
\let\mathgroup\fam
%\let\newfam\new@mathgroup
\@onlypreamble\new@mathgroup
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \section{Macros for setting up the tables}
%
% \begin{macro}{\DeclareFontShape}
%
% \changes{v1.9a}{1992/07/26}{Introduced \cs{DeclareFontShape}}
% The macro |\DeclareFontShape| takes $6$ arguments:
% \begin{macrocode}
\def\DeclareFontShape{\begingroup
% \end{macrocode}
% First we restore the catcodes of all characters used in the syntax.
% \changes{v2.1e}{1994/02/24}
% {Separate restoration of catcodes for fd cmds}
% \begin{macrocode}
\nfss@catcodes
% \end{macrocode}
% We use |\expandafter| |\endgroup| to restore catcode in case
% something goes wrong with the argument parsing (suggested by Tim
% Van Zandt)
% \begin{macrocode}
\expandafter\endgroup
\DeclareFontShape@}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\DeclareFontShape@}
% \changes{v2.1c}{1994/02/07}{revert catcode settings earlier}
% \changes{v3.0m}{1995/11/01}
% {(DPC) Test for \cs{relax} not \cs{undefined}, internal/1933}
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2020/02/02}%
%<latexrelease> {\DeclareFontShape@}{Maybe drop one m}%
\def\DeclareFontShape@#1#2#3#4#5#6{%
\expandafter\ifx\csname #1+#2\endcsname\relax
\@latex@error{Font family `#1+#2' unknown}\@eha
\else
% \end{macrocode}
% If the series value is incorrectly specified with an extra ``m'',
% e.g., ``mc'' instead of just ``c'', drop the surplus ``m'' but
% keep the ``m'' if it is by its own. In that case also issue a
% warning that the declaration needs correction.
% \changes{v3.2f}{2020/02/24}{Drop surplus ``m'' in series when
% defining fontshape (gh/289)}
% \changes{v3.2g}{2020/02/27}{Only ``m'' if the series value is a member
% of a fixed list and issue warning if doing it (gh/293)}
%
% For this we compare the given value \verb=#3= with one where we
% may have dropped an ``m''. If nothing has changes,
% fine. Otherwise there was a wrong value which is now corrected in
% \cs{reservedb} so we use that and also issue a warning.
% \changes{v3.2j}{2021/06/09}{Improve information message}
% \begin{macrocode}
\edef\reserved@a{#3}%
\series@maybe@drop@one@m\reserved@a\reserved@b
\ifx\reserved@a\reserved@b\else
\@latex@note{Font shape #1/#2/#3/#4 has incorrect series
value `#3'.\MessageBreak It should not contain an `m'!
Please correct it.\MessageBreak Found}%
\fi
\expandafter
\xdef\csname#1/#2/\reserved@b/#4\endcsname
{\expandafter\noexpand\csname #5\endcsname}%
%
% \end{macrocode}
% Most of the time \verb=#6= is empty so using \cs{let} to
% \cs{@empty} saves on space compared to using \cs{def}. That's
% really one of the old space saving techniques and probably not
% necessary these days.
% \begin{macrocode}
\def\reserved@a{#6}%
\global
\expandafter\let\csname#5\expandafter\endcsname
\ifx\reserved@a\@empty
\@empty
\else
\reserved@a
\fi
\fi
}
% \end{macrocode}
%
% \begin{macrocode}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\DeclareFontShape@}{Maybe drop one m}%
%<latexrelease>
%<latexrelease>\def\DeclareFontShape@#1#2#3#4#5#6{%
%<latexrelease> \expandafter\ifx\csname #1+#2\endcsname\relax
%<latexrelease> \@latex@error{Font family `#1+#2' unknown}\@eha
%<latexrelease> \else
%<latexrelease> \expandafter
%<latexrelease> \xdef\csname#1/#2/#3/#4\endcsname{\expandafter\noexpand
%<latexrelease> \csname #5\endcsname}%
%<latexrelease> \def\reserved@a{#6}%
%<latexrelease> \global
%<latexrelease> \expandafter\let\csname#5\expandafter\endcsname
%<latexrelease> \ifx\reserved@a\@empty
%<latexrelease> \@empty
%<latexrelease> \else
%<latexrelease> \reserved@a
%<latexrelease> \fi
%<latexrelease> \fi
%<latexrelease> }
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\DeclareFixedFont}
% Define a direct font switch that avoids all overhead.
% \changes{v2.1u}{1994/11/06}{Renamed
% \cs{every@size} to \cs{every@math@size}.}
% \begin{macrocode}
\def\DeclareFixedFont#1#2#3#4#5#6{%
\begingroup
\math@fontsfalse
\every@math@size{}%
\fontsize{#6}\z@
\usefont{#2}{#3}{#4}{#5}%
\global\expandafter\let\expandafter#1\the\font
\endgroup
}
% \end{macrocode}
% \end{macro}
%
%
%
%
% \begin{macro}{\do@subst@correction}
%
% \begin{macrocode}
\def\do@subst@correction{%
\xdef\subst@correction{%
\font@name
\global\expandafter\font
\csname \curr@fontshape/\f@size\endcsname
\noexpand\fontname\font
\relax}%
% \end{macrocode}
% Calling |\subst@correction| after the current group means calling
% it after we have loaded the substitution font which is done
% inside a group.
% \begin{macrocode}
\aftergroup\subst@correction
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DeclareFontFamily}
% \begin{macrocode}
\def\DeclareFontFamily#1#2#3{%
% \end{macrocode}
% If we want fast checking for the encoding scheme we can just
% check for |\T@..| being defined.
% \begin{macrocode}
% \@tempswafalse
% \def\reserved@b{#1}%
% \def\cdp@elt##1##2##3##4{\def\reserved@c{##1}%
% \ifx\reserved@b\reserved@c \@tempswatrue\fi}%
% \cdp@list
% \if@tempswa
\@ifundefined{T@#1}%
{%
\@latex@error{Encoding scheme `#1' unknown}\@eha
}%
{%
% \end{macrocode}
% Now we have to define the macro |\|\meta{\#1}|+|\meta{\#2}
% to contain |#3|. But since most of the time |#3| will be empty
% we use |\let| in a tricky way rather than a simple |\def| since
% this will save internal memory.
% We store the argument |#3| in a temporary macro
% |\reserved@a|.
% \begin{macrocode}
\def\reserved@a{#3}%
% \end{macrocode}
% We compare |\reserved@a| with |\@empty|
% If these two are the same we |\let| the `extra'
% macro equal to |\@empty| which is not the same a doing a |\let|
% to |\reserved@a| --- the latter would blow one extra memory
% location rather then reusing the one from |\@empty|.
% \begin{macrocode}
\global
\expandafter\let\csname #1+#2\expandafter\endcsname
\ifx \reserved@a\@empty
\@empty
\else \reserved@a
\fi
}%
}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\cdp@list}
% We initialize the code page list to be empty.
% \begin{macrocode}
\let\cdp@list\@empty
\@onlypreamble\cdp@list
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\cdp@elt}
% \begin{macrocode}
\let\cdp@elt\relax
\@onlypreamble\cdp@elt
% \end{macrocode}
% \end{macro}
%
%
%
%
% \begin{macro}{\DeclareFontEncoding}
% \begin{macrocode}
\def\DeclareFontEncoding{%
% \end{macrocode}
% First we start with ignoring all blanks and newlines since every
% surplus space in the second or third argument will come out in
% a weird place in the document.
% \changes{v2.1c}{1994/02/07}{revert catcode settings earlier}
% \changes{v2.1t}{1994/10/19}{Add missing \cs{relax}.}
% \changes{v2.1z}{1994/12/06}{use \cs{nfss@catcodes}}
% \begin{macrocode}
\begingroup
\nfss@catcodes
\expandafter\endgroup
\DeclareFontEncoding@}
\@onlypreamble\DeclareFontEncoding
% \end{macrocode}
% \changes{v2.0g}{1993/09/15}
% {Corrected: \cs{default@T} to \cs{default@M}.}
% \begin{macrocode}
\def\DeclareFontEncoding@#1#2#3{%
\expandafter
\ifx\csname T@#1\endcsname\relax
\def\cdp@elt{\noexpand\cdp@elt}%
\xdef\cdp@list{\cdp@list\cdp@elt{#1}%
{\default@family}{\default@series}%
{\default@shape}}%
% \end{macrocode}
% To support encoding dependent commands (like accents) we
% initialise the command
% |\|\meta{encoding}|-cmd| to be |\@changed@cmd|.
% (See \texttt{ltoutenc.dtx} for details.)
% \changes{v2.1l}{1994/05/13}{Init encoding change command}
% \changes{v2.1n}{1994/05/14}{Only init enc change cmd when
% new encoding}
% \changes{v2.1n}{1994/05/14}{Log if encoding is redeclared}
% \begin{macrocode}
\expandafter\let\csname#1-cmd\endcsname\@changed@cmd
\else
\@font@info{Redeclaring font encoding #1}%
\fi
% \end{macrocode}
%
% \begin{macrocode}
\global\@namedef{T@#1}{#2}%
\global\@namedef{M@#1}{\default@M#3}%
% \end{macrocode}
% Keep a record of the last encoding being declared:
% \changes{v3.0w}{1999/01/06}{Added \cs{LastDeclaredEncoding} to
% support cyrillic integration (pr/2988)}
% \begin{macrocode}
\xdef\LastDeclaredEncoding{#1}%
}
\@onlypreamble\DeclareFontEncoding@
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\LastDeclaredEncoding}
% \changes{v3.0w}{1999/01/06}{Added \cs{LastDeclaredEncoding} to
% support cyrillic integration (pr/2988)}
% The last encoding being declared by |\DeclareFontEncoding|.
% \begin{macrocode}
\def\LastDeclaredEncoding{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DeclareFontSubstitution}
% \begin{macrocode}
\def\DeclareFontSubstitution#1#2#3#4{%
\expandafter
\ifx\csname T@#1\endcsname\relax
\@latex@error{Encoding scheme `#1' unknown}\@eha
\else
\begingroup
% \end{macrocode}
% \changes{v3.0x}{2002/10/02}{Adding \cs{LastDeclaredEncoding}
% introduced a bug as on some occasions that macro name was stored
% in the internal lists instead of the actual encoding. (pr/3459)}
% We loop through the |\cdp@list| and rebuild it anew in |\toks@|
% thereby replacing the defaults for the encoding in question with
% the new defaults. It is important to store the encoding to test
% against expanded in |\reserved@a| since it might just be
% |\LastDeclaredEncoding| that is passed as |#1|.
% \begin{macrocode}
\edef\reserved@a{#1}%
\toks@{}%
\def\cdp@elt##1##2##3##4{%
\def\reserved@b{##1}%
\ifx\reserved@a\reserved@b
% \end{macrocode}
% Here we use the new defaults but we use |##1| (i.e., the encoding
% name already stored previously) since we know that it is expanded.
% \begin{macrocode}
\addto@hook\toks@{\cdp@elt{##1}{#2}{#3}{#4}}%
\else
% \end{macrocode}
% If |\reserved@a| and |\reserved@b| differ then we simply copy
% from the old list to the new.
% \begin{macrocode}
\addto@hook\toks@{\cdp@elt{##1}{##2}{##3}{##4}}%
\fi}%
\cdp@list
\xdef\cdp@list{\the\toks@}%
\endgroup
\global
\@namedef{D@#1}{%
\def\default@family{#2}%
\def\default@series{#3}%
\def\default@shape{#4}%
}%
\fi
}
\@onlypreamble\DeclareFontSubstitution
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\DeclareFontEncodingDefaults}
% \begin{macrocode}
\def\DeclareFontEncodingDefaults#1#2{%
\ifx\relax#1\else
\ifx\default@T\@empty\else
\@font@info{Overwriting encoding scheme text defaults}%
\fi
\gdef\default@T{#1}%
\fi
\ifx\relax#2\else
\ifx\default@M\@empty\else
\@font@info{Overwriting encoding scheme math defaults}%
\fi
\gdef\default@M{#2}%
\fi
}
\@onlypreamble\DeclareFontEncodingDefaults
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\default@T}
% \begin{macro}{\default@M}
% \begin{macrocode}
\let\default@T\@empty
\let\default@M\@empty
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\DeclarePreloadSizes}
% \begin{macrocode}
\def\DeclarePreloadSizes#1#2#3#4#5{%
\@ifundefined{T@#1}%
{\@latex@error{Encoding scheme `#1' unknown}\@eha}%
{%
% \end{macrocode}
% Don't know at the moment what this group here does!
% \begin{macrocode}
\begingroup
% \end{macrocode}
% We define a macro |\reserved@f|\footnote{We cannot use
% {\ttfamily\bslash @tempa}
% since it is needed in
% {\ttfamily\bslash pickup@font}.}
% that grabs the next \emph{size} and loads the corresponding
% font.
% This is done by delimiting |\reserved@f|'s only argument by the
% \textsf{token} |,| (comma).
% \begin{macrocode}
\def\reserved@f##1,{%
% \end{macrocode}
% The end of the list will be detected when there are no more
% elements, i.e.\ when |\reserved@f|'s argument is empty.
% The trick used here is explained in Appendix~D of the
% \TeX{}book: if the argument is empty the |\if|
% will select the first clause and |\let| |\reserved@f|
% equal to |\relax|.
% (We use the |>| character here since it cannot appear
% in font file names.)
% \changes{v1.2j}{1990/06/24}{Missing percent added.}
% \begin{macrocode}
\if>##1>%
\let\reserved@f\relax
\else
% \end{macrocode}
% Otherwise, we define |\font@name| appropriately and
% call |\pickup@font| to do the work.
% Note that the requested |\curr@fontshape|
% combination must have been defined, or you will get an error.
% The definition of |\font@name| is carried out globally
% to be consistent with the rest of the code in this file.
% \begin{macrocode}
\xdef\font@name{\csname#1/#2/#3/#4/##1\endcsname}%
\pickup@font
% \end{macrocode}
% Now we forget the name of the font just loaded.
% More precisely, we set the corresponding control sequence
% to |\relax|. This means that later on, when the font
% is first used, the macro |\define@newfont| is called
% again to execute the `extra' macro for this font.
% \changes{v1.2d}{1990/01/27}{Font identifier set to \cs{relax}.}
% \begin{macrocode}
\global\expandafter\let\font@name\relax
\fi
% \end{macrocode}
% Finally we call |\reserved@f| again to process the next
% \emph{size}. If |\reserved@f| was |\let| equal to |\relax|
% this will end the macro.
% \begin{macrocode}
\reserved@f}%
% \end{macrocode}
% We finish with reinserting the list of sizes after the
% |\reserved@f|
% macro and appending an empty element so that the end of the list
% is recognized properly.
% \begin{macrocode}
\reserved@f#5,,%
\endgroup
}%
}
\@onlypreamble\DeclarePreloadSizes
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\ifmath@fonts}
% We need a switch to decide if we have to switch math fonts.
% For this purpose we provide |\ifmath@fonts|
% that can be set to true or false by the |\S@...| macros
% depending on if math fonts
% are provided for this size or not.
% The default is of course to switch all fonts.
% \begin{macrocode}
\newif\ifmath@fonts \math@fontstrue
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\DeclareMathSizes}
% \begin{macro}{\DeclareMathSizes*}
% |\DeclareMathSizes| takes the text size, math text size, math
% script size, and math scriptscript size as arguments and defines
% the right |\S@|\dots{} macro.
%
% \begin{macrocode}
\def\DeclareMathSizes{%
\@ifstar{\@DeclareMathSizes\math@fontsfalse}%
{\@DeclareMathSizes{}}}
\@onlypreamble\DeclareMathSizes
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@DeclareMathSizes}
% \changes{v3.0p}{1996/07/26}{use faster \cs{if} test}
% This modification by Michael J. Downes on comp.text.tex on 2002/10/17
% allows the user to have settings such as\\
% |\DeclareMathSizes{9.5dd}{9.5dd}{7.4dd}{6.6dd}|.
% \changes{v3.0y}{2015/01/11}{Allow arbitrary units (latexrelease)}
% \begin{macrocode}
%</2ekernel>
%<latexrelease>\IncludeInRelease{2015/01/01}{\@DeclareMathSizes}%
%<latexrelease> {Arbitrary units in \DeclareMathSizes}%
%<*2ekernel|latexrelease>
\def\@DeclareMathSizes #1#2#3#4#5{%
\@defaultunits\dimen@ #2pt\relax\@nnil
\if $#3$%
\expandafter\let\csname S@\strip@pt\dimen@\endcsname\math@fontsfalse
\else
\@defaultunits\dimen@ii #3pt\relax\@nnil
\@defaultunits\@tempdima #4pt\relax\@nnil
\@defaultunits\@tempdimb #5pt\relax\@nnil
\toks@{#1}%
\expandafter\xdef\csname S@\strip@pt\dimen@\endcsname{%
\gdef\noexpand\tf@size{\strip@pt\dimen@ii}%
\gdef\noexpand\sf@size{\strip@pt\@tempdima}%
\gdef\noexpand\ssf@size{\strip@pt\@tempdimb}%
\the\toks@
}%
\fi
}%
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}{\@DeclareMathSizes}%
%<latexrelease> {Arbitrary units in \DeclareMathSizes}%
%<latexrelease>\def\@DeclareMathSizes#1#2#3#4#5{%
%<latexrelease> \@defaultunits\dimen@#2pt\relax\@nnil
%<latexrelease> \if$#3$%
%<latexrelease> \expandafter \let
%<latexrelease> \csname S@\strip@pt\dimen@\endcsname
%<latexrelease> \math@fontsfalse
%<latexrelease> \else
%<latexrelease> \expandafter \gdef
%<latexrelease> \csname S@\strip@pt\dimen@\endcsname
%<latexrelease> {\gdef\tf@size{#3}\gdef\sf@size{#4}%
%<latexrelease> \gdef\ssf@size{#5}%
%<latexrelease> #1%
%<latexrelease> }%
%<latexrelease> \fi}%
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
%
% \begin{macrocode}
\@onlypreamble\@DeclareMathSizes
% \end{macrocode}
% \end{macro}
%
%
%
% \section{Selecting a new font}
%
% \subsection{Macros for the user}
%
%
% \begin{macro}{\fontencoding}
% \changes{v2.1j}{1994/05/12}{Use \cs{DeclareRobustCommand}.}
% \begin{macro}{\f@encoding}
% As we said in the introduction a font is described by four parameters.
% We first define macros to specify the wanted \emph{family},
% \emph{series}, or \emph{shape}.
% These are simply recorded in internal macros
% |\f@family|, |\f@series|, and |\f@shape|, resp.
% We use |\edef|'s so that the arguments can also be macros.
% \begin{macrocode}
\DeclareRobustCommand\fontencoding[1]{%
\expandafter\ifx\csname T@#1\endcsname\relax
\@latex@error{Encoding scheme `#1' unknown}\@eha
\else
\edef\f@encoding{#1}%
\ifx\cf@encoding\f@encoding
% \end{macrocode}
% If the new encoding is the same as the old
% encoding we have nothing to do.
% However, in case we had a sequence of several encoding changes
% without a |\selectfont| in-between we can save processing by
% making sure that |\enc@update| is |\relax|.
% \begin{macrocode}
\let\enc@update\relax
\else
% \end{macrocode}
% If current and new encoding differ we define the macro
% |\enc@update|
% to contain all updates necessary at |\selectfont| time.
% \begin{macrocode}
\let\enc@update\@@enc@update
\fi
\fi
}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@@enc@update}
% \begin{macrocode}
\def\@@enc@update{%
% \end{macrocode}
% When |\@@enc@update| is executed |\f@encoding| holds the encoding
% name
% for the new encoding and |\cf@encoding| the name of the last active
% encoding.
%
% We start by setting the init command for encoding dependent
% macros to |\@changed@cmd|.
% \begin{macrocode}
\expandafter
\let
\csname\cf@encoding -cmd\endcsname
\@changed@cmd
% \end{macrocode}
% Then we turn the one for the new encoding to |\@current@cmd| (see
% \texttt{ltoutenc.dtx} for further explanations).
% \begin{macrocode}
\expandafter
\let
\csname\f@encoding-cmd\endcsname
\@current@cmd
% \end{macrocode}
% We execute the default settings |\default@T|, followed by the one
% for the new encoding.
% \begin{macrocode}
\default@T
\csname T@\f@encoding\endcsname
% \end{macrocode}
% Finally we change the default substitution values, disable
% |\enc@update| and make |\f@encoding| officially the current
% encoding.
% \begin{macrocode}
\csname D@\f@encoding\endcsname
\let\enc@update\relax
\let\cf@encoding\f@encoding
}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\enc@update}
% \changes{v2.1m}{1994/05/14}{Macro added}
% The default action in |\selectfont| is to do nothing.
% \begin{macrocode}
\let\enc@update\relax
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fontfamily}
% \changes{v2.1j}{1994/05/12}{Use \cs{DeclareRobustCommand}.}
% \begin{macro}{\f@family}
% \begin{macro}{\fontseries}
% \changes{v2.1j}{1994/05/12}{Use \cs{DeclareRobustCommand}.}
% \begin{macro}{\f@series}
% \begin{macro}{\fontshape}
% \changes{v2.1j}{1994/05/12}{Use \cs{DeclareRobustCommand}.}
% \changes{v2.1y}{1994/11/30}{Use \cs{@current@cmd} in
% \cs{@@enc@update}. ASAJ.}
% \begin{macro}{\f@shape}
% \begin{macrocode}
\DeclareRobustCommand\fontfamily[1]{\edef\f@family{#1}}
% \end{macrocode}
% There are now defined later (and differently).
% \begin{macrocode}
%\DeclareRobustCommand\fontseries[1]{\edef\f@series{#1}}
%\DeclareRobustCommand\fontshape [1]{\edef\f@shape{#1}}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\usefont}
% Some handy abbreviation if you want to get some particular font
% in the current size. If also the size should change one has to
% issue a |\fontsize| command first.
%
% \cs{fontencoding} needs to do some setup work so we call that,
% but instead of calling \cs{fontfamily}, \cs{fontseries} and
% \cs{fontshape} it earlier versions of this code did, we now set
% \cs{f@family}, etc.\ directly. If we would call \cs{fontseries}
% or \cs{fontshape} as it
% was done in the past, they would now interact with the existing
% series and shape which is not desired if we intend to use an
% explicit font shape!
% \changes{v3.2e}{2019/12/17}{Don't call \cs{fontseries} or \cs{fontshape}}
% \changes{v3.2h}{2020/12/10}{Drop ``m'' if the series value is a member
% of a fixed list and issue warning if doing it (gh/453)}
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2021/06/01}%
%<latexrelease> {\usefont}{Force font face}%
\DeclareRobustCommand\usefont[4]{\fontencoding{#1}%
\edef\f@family{#2}%
\set@target@series{#3}%
\edef\f@shape{#4}%
% \end{macrocode}
% Any earlier \cs{fontseries}, etc.\ should be canceled and we
% should switch unconditionally to the requested font face so we
% drop any code that may have been stored in
% \cs{delayed@f@adjustment}.
% \changes{v3.2i}{2021/04/26}{Unconditionally switch to the requested
% font face (gh/444)}
% \begin{macrocode}
\let\delayed@f@adjustment\@empty
\selectfont
\ignorespaces}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{2020/02/02}%
%<latexrelease> {\usefont}{Drop m in usefont}%
%<latexrelease>
%<latexrelease>\DeclareRobustCommand\usefont[4]{\fontencoding{#1}%
%<latexrelease> \edef\f@family{#2}%
%<latexrelease> \set@target@series{#3}%
%<latexrelease> \edef\f@shape{#4}\selectfont
%<latexrelease> \ignorespaces}
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\usefont}{Drop m in usefont}%
%<latexrelease>
%<latexrelease>\DeclareRobustCommand\usefont[4]{\fontencoding{#1}%
%<latexrelease> \edef\f@family{#2}%
%<latexrelease> \edef\f@series{#3}%
%<latexrelease> \edef\f@shape{#4}\selectfont
%<latexrelease> \ignorespaces}
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\linespread}
% \changes{v2.1j}{1994/05/12}{New macro}
% \changes{v2.1p}{1994/05/16}{Remove surplus braces}
% The command |\linespread| changes the current |\baselinestretch|
% by calling |\set@fontsize|. The values for |\f@size| and
% |\f@baselineskip| will be left unchanged.
% \begin{macrocode}
\DeclareRobustCommand\linespread[1]
{\set@fontsize{#1}\f@size\f@baselineskip}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\fontsize}
% \changes{v2.1j}{1994/05/12}{Redefined to use \cs{set@fontsize}}
% \changes{v2.1p}{1994/05/16}{Pass \cs{baselinstretch} not
% \cs{f@linespread}}
% We also define a macro that allows to specify a size. In this
% case, however, we also need the value of |\baselineskip|. As the
% first argument to |\set@fontsize| we pass the current value of
% |\baselinestretch|. This will either match the internal value (in
% which case nothing changes, or it will be an updated value due to
% a user change of that macro using |\renewcommand|. If we would
% pass the internal |\f@linespread| such a change would be
% effectively overwritten by a size change.
% \begin{macrocode}
\DeclareRobustCommand\fontsize[2]
{\set@fontsize\baselinestretch{#1}{#2}}
% \end{macrocode}
% \end{macro}
%
%
% \changes{v2.1n}{1994/05/14}{Set defaults for all \cs{f@...}}
%
% \begin{macro}{\f@linespread}
% \changes{v2.1j}{1994/05/12}{New macro}
% This macro holds the current internal value for
% |\baselinestretch|.
% \begin{macrocode}
\let\f@family\@empty
\let\f@series\@empty
\let\f@shape\@empty
\let\f@size\@empty
\let\f@baselineskip\@empty
\let\f@linespread\@empty
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\cf@encoding}
% \changes{v2.1u}{1994/11/06}{New macro}
% \begin{macrocode}
\let\f@encoding\@empty
\let\cf@encoding\@empty
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\@defaultunits}
%
% The function |\@defaultunits| when wrapped around a dimen or skip
% assignment supplies default units. Usage:
%
% |\@defaultunits\dimen@=#1pt\relax\@nnil|
%
% Note: the |\relax| is *important*. Other units can be substituted
% for the `pt' if desired.
%
% We use |\remove@to@nnil| as an auxiliary macros for
% |\@defaultunits|. It just has to gobble the supplied default unit
% `pt' or whatever, if it wasn't used in the assignment.
% \begin{macrocode}
\def\@defaultunits{\afterassignment\remove@to@nnil}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\strip@pt}
% \begin{macro}{\rem@pt}
% This macro strips the characters |pt| produced by using |\the|
% on a dimen register.
% \begin{macrocode}
\begingroup
\catcode`P=12
\catcode`T=12
\lowercase{
\def\x{\def\rem@pt##1.##2PT{##1\ifnum##2>\z@.##2\fi}}}
\expandafter\endgroup\x
\def\strip@pt{\expandafter\rem@pt\the}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\mathversion}
% \changes{v1.0h}{1989/04/29}{Test if version defined added.}
% \changes{v1.0m}{1989/09/14}
% {Corrected typo: \cs{endscname} to \cs{endcsname}.}
% \changes{v2.1j}{1994/05/12}{Use \cs{DeclareRobustCommand}.}
% \begin{macro}{\math@version}
% |\mathversion| takes the math \emph{version} name as
% argument, defines |\math@version| appropriately and switches
% to the font selected
% forcing a call to |\glb@settings| if the \emph{version} is
% known to the system.
% \changes{v1.0p}{1989/11/14}{Math version prefix `mv@' added.}
% \changes{v1.0r}{1989/11/22}
% {\cs{def} $\to$ \cs{edef} for \cs{math@version}.}
% \changes{v1.2g}{1990/02/16}{\cs{@nomath} added.}
% \changes{v2.1a}{1994/01/17}{New math font setup}
% \begin{macrocode}
\DeclareRobustCommand\mathversion[1]
{\@nomath\mathversion
\expandafter\ifx\csname mv@#1\endcsname\relax
\@latex@error{Math version `#1' is not defined}\@eha\else
\edef\math@version{#1}%
% \end{macrocode}
% We need to force a math font setup both now and at the point
% where we return to the previous math version.
% Forcing a math font setup can simply be done by setting
% |\glb@currsize| to an invalid value since this will trigger the
% setup when the formula starts.
% \begin{macrocode}
\gdef\glb@currsize{}%
% \end{macrocode}
% When the scope of the current |\mathversion| ends we need to
% restore the old setup. However this time we need to force it
% directly at least if we are inside math, otherwise we could wait.
% Another way to enhance this code here is todo the setting only if
% the version really has changed after all. This might be
% interesting in case of \texttt{amstext} and \texttt{boldsymbol}.
% \changes{v2.1b}{1994/01/25}{Corrections for math setup}
% \begin{macrocode}
\aftergroup\glb@settings
\fi}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% If \TeX{} would support a hook just before the end of a formula
% (opposite of |\everymath| so to speak) the implementation of the
% algorithm would be much simpler because in that case we would set up
% the correct math fonts at this point without having to worry about
% incorrect settings due to nesting. The same would be true if in
% \LaTeX{} the use of |$| (as the primitive \TeX{} command) would be
% impossible and instead only a higher-level interface would be
% available. Note that this does not mean that a |$| couldn't be the
% short-hand for starting and stopping that higher-level interface, it
% only means that the direct \TeX{} function must be hidden.
%
% Anyway, since we don't have this and won't have it in \LaTeXe{} we
% need to implement it in a somewhat slower way.
%
%
% We test for the current math font setup on entry of a formula,
% i.e., on the
% hooks |\everymath| and |\everydisplay|. But since these hooks may
% contain user data we provide ourselves with an internal version of
% these hooks which stays frozen.
%
%
% \begin{macro}{\frozen@everymath}
% \changes{v2.1a}{1994/01/17}{New math font setup}
% \begin{macro}{\frozen@everydisplay}
% New internal names for |\everymath| and |\everydisplay|.
% \begin{macrocode}
\let\frozen@everymath\everymath
\let\frozen@everydisplay\everydisplay
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\everymath}
% \changes{v2.1a}{1994/01/17}{New math font setup}
% \begin{macro}{\everydisplay}
% \changes{v2.1a}{1994/01/17}{New math font setup}
% Now we provide now user hooks that will be called in the
% frozen internals.
% \begin{macrocode}
\newtoks\everymath
\newtoks\everydisplay
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
%
% \begin{macro}{\frozen@everydisplay}
% \changes{v2.1a}{1994/01/17}{New math font setup}
% Now we define the behaviour of the frozen hooks: first
% check the math setup then call the user hook.
%
% The check code may push tokens after the math formula with
% \cs{aftergroup} and they would prevent a \verb=$$= from dropping
% following spaces. We therefore use a switch to be set as the
% first thing after the group so that following code can determine
% if there was a display or some inline math (in the latter case
% we better not drop spaces).
% After setting the switch we also have to place \cs{ignorespaces}
% because setting the switch may be the only thing that happens
% after the display.
% \changes{v3.2k}{2022/07/04}{Ignore spaces if necessary (gh/886)}
% The issue with handling of spaces was found in 2022, but it is
% really a bug fix for the code added in 2021/11.
% \begin{macrocode}
%</2ekernel>
%<latexrelease>\IncludeInRelease{2021/11/15}
%<latexrelease> {\frozen@everydisplay}{Handle spaces after math}%
%<*2ekernel|latexrelease>
\frozen@everydisplay = {%
\aftergroup\@ignoretrue \aftergroup\ignorespaces
\check@mathfonts
\the\everydisplay}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\frozen@everymath}
% \changes{v2.1a}{1994/01/17}{New math font setup}
% \changes{v3.2k}{2022/07/04}{Ignore spaces if necessary (gh/886)}
% The frozen code for inline math is similar, except that here we
% do not want to drop following spaces.
% \begin{macrocode}
\frozen@everymath = {%
\aftergroup\@ignorefalse
\check@mathfonts
\the\everymath}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{2020/10/01}
%<latexrelease> {\frozen@everydisplay}{Handle spaces after math}%
%<latexrelease>
%<latexrelease>\frozen@everydisplay = {\check@mathfonts
%<latexrelease> \the\everydisplay}
%<latexrelease>\frozen@everymath = {\check@mathfonts
%<latexrelease> \the\everymath}
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
%
%
%
%
%
%
% \changes{v3.0q}{1996/07/27}{\cs{if@inmath} switch removed}
%
% \begin{macro}{\curr@math@size}
% \changes{v2.1a}{1994/01/17}{New math font setup}
% This holds locally the current math size.
% \begin{macrocode}
\let\curr@math@size\@empty
% \end{macrocode}
% \end{macro}
%
%
%
%
% \subsection{Macros for loading fonts}
%
% \begin{macro}{\pickup@font}
% The macro |\pickup@font| which is used in
% |\selectfont| is very simple:
% if the font name is undefined (i.e.\ not known yet) it calls
% |\define@newfont| to load it.
% \begin{macrocode}
\def\pickup@font{%
\expandafter \ifx \font@name \relax
\define@newfont
\fi}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\split@name}
% |\pickup@font| assumes that |\font@name| is set
% but it is sometimes called when |\f@family|, |\f@series|,
% |\f@shape|, or |\f@size| may have the wrong settings
% (see, e.g., the definition of |\getanddefine@fonts|).
% Therefore we need a macro to extract font \emph{family},
% \emph{series}, \emph{shape}, and \emph{size} from the font name.
% To this end we define |\split@name| which takes the font
% name as a list of characters of |\catcode| 12 (without the
% backslash at the beginning) delimited by the
% special control sequence |\@nil|.
% This is not very complicated: we first ensure that |/| has
% the right |\catcode|
% \begin{macrocode}
{\catcode`\/=12
% \end{macrocode}
% and define |\split@name| so that it will define our
% private |\f@encoding|, |\f@family|, |\f@series|, |\f@shape|,
% and |\f@size| macros.
% \changes{v1.9a}{1992/07/26}{Added splitting into \cs{f@encoding}.}
% \begin{macrocode}
\gdef\split@name#1/#2/#3/#4/#5\@nil{\def\f@encoding{#1}%
\def\f@family{#2}%
\def\f@series{#3}%
\def\f@shape{#4}%
\def\f@size{#5}}}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\curr@fontshape}
% Abbreviation which may get removed again for speed.
% \changes{v1.9a}{1992/07/26}{}
% \begin{macrocode}
\def\curr@fontshape{\f@encoding/\f@family/\f@series/\f@shape}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\define@newfont}
% Now we can tackle the problem of defining a new font.
% \changes{v1.9a}{1992/07/26}{}
% \begin{macrocode}
\def\define@newfont{%
% \end{macrocode}
% We have already mentioned that the \textsf{token} list that
% |\split@name| will get as argument must not start with
% a backslash.
% To reach this goal we will set the |\escapechar| to $-1$ so
% that the |\string| primitive will not generate an
% escape character.
% To keep this change local we open a group. We use
% |\begingroup| for this purpose since |\define@newfont|
% might be called in math mode, and an empty
% |\bgroup|\ldots|\egroup| would add an empty Ord atom
% to the math list and thus affect the spacing.
%
% Also locally redefine |\typeout| so that `No file ...fd'
% Warnings become Font Info message just sent to the log file.
% \changes{v1.0q}{1989/11/19}{Group added.}
% \changes{v3.0m}{1995/11/17}{Redefine \cs{typeout} latex/1676}
% \begin{macrocode}
\begingroup
\let\typeout\@font@info
\escapechar\m@ne
% \end{macrocode}
% Then we extract \emph{encoding scheme}, \emph{family},
% \emph{series}, \emph{shape},
% and \emph{size} from the font name.
% Note the four |\expandafter|'s so that |\font@name| is
% expanded first, then |\string|, and finally
% |\split@name|.
% \begin{macrocode}
\expandafter\expandafter\expandafter
\split@name\expandafter\string\font@name\@nil
% \end{macrocode}
% If the |\curr@fontshape| combination is not available,
% (i.e.\ undefined) we call the macro |\wrong@fontshape| to take
% care of this case. Otherwise |\extract@font|
% will load the external font for us.
% \changes{v1.2f}{1990/01/28}{Added call to \cs{curr@fontshape} macro
% to allow substitution.}
% \begin{macrocode}
% \expandafter\ifx
% \csname\curr@fontshape\endcsname \relax
\try@load@fontshape % try always
% \fi
\expandafter\ifx
\csname\curr@fontshape\endcsname \relax
\wrong@fontshape\else
% \end{macrocode}
% To allow substitution we call the |curr@fontshape| macro
% which usually will expand to |\relax| but may hold code for
% substitution (see |\subst@fontshape| definition).
% \begin{macrocode}
% \csname\curr@fontshape\endcsname
\extract@font\fi
% \end{macrocode}
% We are nearly finished and must only restore the
% |\escapechar| by closing the group.
% \begin{macrocode}
\endgroup}
% \end{macrocode}
%
%
% \changes{v3.2b}{2019/02/07}{Changed wording of warning (github/107)}
% \begin{macrocode}
\def\try@load@fontshape{%
\expandafter
\ifx\csname \f@encoding+\f@family\endcsname\relax
\@font@info{Trying to load font information for
\f@encoding+\f@family}%
% \end{macrocode}
% We predefine this combination to be |\@empty| which means that
% next time we don't try again unnecessary in case we don't find a
% |.fd| file. If the file contains a |\DeclareFontFamily| command
% than this setting will be overwritten.
% \changes{v2.1e}{1994/02/24}
% {Separate restoration of catcodes for fd cmds}
% \changes{v2.1l}{1994/05/13}{Use \cs{@input@} for fd files}
% \begin{macrocode}
\global\expandafter\let
\csname\f@encoding+\f@family\endcsname\@empty
% \end{macrocode}
% Set the catcodes used in the syntax, but do it only once (this
% will be restored at the end of the font loading group).
% \changes{v3.0t}{1997/10/21}{Move \cs{makeatletter} to
% \cs{nfss@catcodes}.}
% \begin{macrocode}
\nfss@catcodes
\let\nfss@catcodes\relax
% \end{macrocode}
%
% \changes{v3.0s}{1996/11/18}
% {(DPC) lowercase fd file names. internal/1044}
% For increased portability make the external filename
% monocase, but look for the (old style) mixed case
% filename if the first attempt fails.
%
% On any monocase system this means that the file is looked for twice
% which takes up time and string space, but at least for this release
% Check for both names to give people time to re-install their private
% fd files with lowercase names.
% \begin{macrocode}
\edef\reserved@a{%
\lowercase{%
\noexpand\InputIfFileExists{\f@encoding\f@family.fd}}}%
\reserved@a\relax
{\@input@{\f@encoding\f@family.fd}}%
\fi}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\nfss@catcodes}
% \changes{v2.1e}{1994/02/24}
% {Separate restoration of catcodes for fd cmds}
% This macro should contain the standard |\catcode| assignments to
% all characters which are used in the commands found in an
% \texttt{.fd} file and which might have special |\catcode|s in the
% middle of a document. If necessary, this list can be extended in
% a package file using a suitable number of |\expandafter|, i.e.,
%\begin{verbatim}
% \expandafter\def\expandafter\nfss@catcodes
% \expandafter{\nfss@catcodes <additional settings>}
%\end{verbatim}
% Note, that this macro might get executed several times since it
% is also called by |\DeclareFontShape|, thus it probably should
% not be misused as a general purpose hook.
% \begin{macrocode}
\def\nfss@catcodes{%
% \end{macrocode}
% We start by making |@| a letter and ignoring all blanks and newlines.
% \changes{v2.1z}{1994/12/06}{Added tab char as well}
% \changes{v3.0p}{1996/07/26}{omit \cs{relax} as not needed}
% \changes{v3.0t}{1997/10/21}{Moved \cs{makeatletter} from
% \cs{try@load@font@shape}.}
% \begin{macrocode}
\makeatletter
\catcode`\ 9%
\catcode`\^^I9%
\catcode`\^^M9%
% \end{macrocode}
% Then we set up |\|, |{|, |}|, |#| and |%| in case an \texttt{.fd}
% file is loaded during a verbatim environment.
% \changes{v3.0n}{1995/11/27}{Reset hash, for definitions in fd files}
% \changes{v3.00}{1995/12/06}{Reset hat, for typeouts etc in fd files}
% \begin{macrocode}
\catcode`\\\z@
\catcode`\{\@ne
\catcode`\}\tw@
\catcode`\#6%
\catcode`\^7%
\catcode`\%14%
% \end{macrocode}
% The we make sure that the important syntax parts have the right
% |\catcode|.
% \changes{v2.1s}{1994/09/16}{Reset [ and ] as well, just in case}
% \changes{v3.0r}{1996/08/25}{Reset the acute, grave and double quote
% chars as well}
% \begin{macrocode}
\@makeother\<%
\@makeother\>%
\@makeother\*%
\@makeother\.%
\@makeother\-%
\@makeother\/%
\@makeother\[%
\@makeother\]%
\@makeother\`%
\@makeother\'%
\@makeother\"%
}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\LoadFontDefinitionFile}
% Load and \texttt{.fd} files for some encoding and family (if it exists).
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2020/02/02}%
%<latexrelease> {\LoadFontDefinitionFile}{Loading .fd files}%
\def\LoadFontDefinitionFile#1#2{%
\begingroup
\edef\f@encoding{#1}%
\edef\f@family{#2}%
\try@load@fontshape
\endgroup
}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\LoadFontDefinitionFile}{Loading .fd files}%
%<latexrelease>
%<latexrelease>\let\LoadFontDefinitionFile\@undefined
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\DeclareFontFamilySubstitution}
% The idea for this macro is stolen from the \texttt{substitutefont}
% package by Günter Milde, with some modifications and a new name.
%
% Its purpose is to provide characters in a special encoding that
% are not available in the current font family to be taken from a
% different family that is visually compatible (or not if you
% choose badly). For example, you can match the GFS Didot Greek
% characters with \TeX{} Gyre Pagella (Palatino) by specifying
%\begin{verbatim}
% \DeclareFontFamilySubstitution{LGR}{qpl}{udidot}
%\end{verbatim}
% This way if you ask for the \texttt{LGR} encoding in for the
% \texttt{qpl} family you get the characters from the
% \texttt{udidot} family substituted.
%
% We need to ensure that the macro is defined with
% \cs{nfss@catcodes} in force (not quite sure why at the moment to
% be honest).
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2020/02/02}%
%<latexrelease> {\DeclareFontFamilySubstitution}{Provide family substitution}%
\begingroup
\nfss@catcodes
\gdef\DeclareFontFamilySubstitution#1#2#3{%
% \end{macrocode}
% We only provide a set of silent substitutions. The package also
% (re)declared the family, but this is incorrect in my eyes and it
% is better to handle that differently.
%
% Of course the families may still need loading at
% this point and so we arrange for this. Otherwise we might run into
% trouble because the necessary \cs{DeclareFontFamily} has not been
% seen.
% \begin{macrocode}
\LoadFontDefinitionFile{#1}{#2}%
\LoadFontDefinitionFile{#1}{#3}%
% \end{macrocode}
%
% \begin{macrocode}
\DeclareFontShape{#1}{#2}{m}{it}{<->ssub * #3/m/it}{}%
\DeclareFontShape{#1}{#2}{m}{n}{<->ssub * #3/m/n}{}%
\DeclareFontShape{#1}{#2}{m}{sc}{<->ssub * #3/m/sc}{}%
\DeclareFontShape{#1}{#2}{m}{sl}{<->ssub * #3/m/sl}{}%
% \end{macrocode}
% These days a few more shapes might be around, so we declare those
% too. If they don't exist then after the first substitution normal
% fallbacks will happen.
% \begin{macrocode}
\DeclareFontShape{#1}{#2}{m}{sw}{<->ssub * #3/m/sw}{}%
\DeclareFontShape{#1}{#2}{m}{scit}{<->ssub * #3/m/scit}{}%
\DeclareFontShape{#1}{#2}{m}{scsl}{<->ssub * #3/m/scsl}{}%
% \end{macrocode}
% Same game with \texttt{b} and \texttt{bx}, for other weights you
% are on your own:
% \begin{macrocode}
\DeclareFontShape{#1}{#2}{b}{it}{<->ssub * #3/b/it}{}%
\DeclareFontShape{#1}{#2}{b}{n}{<->ssub * #3/b/n}{}%
\DeclareFontShape{#1}{#2}{b}{scit}{<->ssub * #3/b/scit}{}%
\DeclareFontShape{#1}{#2}{b}{scsl}{<->ssub * #3/b/scsl}{}%
\DeclareFontShape{#1}{#2}{b}{sc}{<->ssub * #3/b/sc}{}%
\DeclareFontShape{#1}{#2}{b}{sl}{<->ssub * #3/b/sl}{}%
\DeclareFontShape{#1}{#2}{b}{sw}{<->ssub * #3/b/sw}{}%
\DeclareFontShape{#1}{#2}{bx}{it}{<->ssub * #3/bx/it}{}%
\DeclareFontShape{#1}{#2}{bx}{n}{<->ssub * #3/bx/n}{}%
\DeclareFontShape{#1}{#2}{bx}{scit}{<->ssub * #3/bx/scit}{}%
\DeclareFontShape{#1}{#2}{bx}{scsl}{<->ssub * #3/bx/scsl}{}%
\DeclareFontShape{#1}{#2}{bx}{sc}{<->ssub * #3/bx/sc}{}%
\DeclareFontShape{#1}{#2}{bx}{sl}{<->ssub * #3/bx/sl}{}%
\DeclareFontShape{#1}{#2}{bx}{sw}{<->ssub * #3/bx/sw}{}%
}
\endgroup
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\DeclareFontFamilySubstitution}{Provide family substitution}%
%<latexrelease>
%<latexrelease>\let\DeclareFontFamilySubstitution\@undefined
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\DeclareErrorFont}
% Declare the last resort shape! We assume that in this fontshape
% there is a 10pt font but it doesn't really matter. We only loose
% one macro name if the assumption is false. But at least the font
% should be there!
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2019/10/01}%
%<latexrelease> {\DeclareErrorFont}{No side effects please}%
\def\DeclareErrorFont#1#2#3#4#5{%
\xdef\error@fontshape{%
\noexpand\expandafter\noexpand\split@name\noexpand\string
\expandafter\noexpand\csname#1/#2/#3/#4/#5\endcsname
\noexpand\@nil}%
% \end{macrocode}
% Initialize all those internal variables which may or may not have
% values in the first seconds of NFSS' bootstrapping process. Later
% on such values will be updated when an encoding is selected, etc.
%
% We definitely don't want to set |\f@encoding|; we can set all the
% others since if they are left ``blank'' any selection would grab
% ``error default values'' as well. However, this probably should
% go also---and now it did.
% \changes{v2.1n}{1994/05/14}{Don't set \cs{f@encoding}}
% \changes{v3.2c}{2019/07/09}{Don't set any \cs{f@...} macros}
% \begin{macrocode}
% \gdef\f@encoding{#1}%
\gdef\default@family{#2}%
\gdef\default@series{#3}%
\gdef\default@shape{#4}%
}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\DeclareErrorFont}{No side effects please}%
%<latexrelease>
%<latexrelease>\def\DeclareErrorFont#1#2#3#4#5{%
%<latexrelease> \xdef\error@fontshape{%
%<latexrelease> \noexpand\expandafter\noexpand\split@name\noexpand\string
%<latexrelease> \expandafter\noexpand\csname#1/#2/#3/#4/#5\endcsname
%<latexrelease> \noexpand\@nil}%
%<latexrelease> \gdef\default@family{#2}%
%<latexrelease> \gdef\default@series{#3}%
%<latexrelease> \gdef\default@shape{#4}%
%<latexrelease> \global\let\f@family\default@family
%<latexrelease> \global\let\f@series\default@series
%<latexrelease> \global\let\f@shape\default@shape
%<latexrelease> \gdef\f@size{#5}%
%<latexrelease> \gdef\f@baselineskip{#5pt}%
%<latexrelease>}
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
%
% \begin{macrocode}
\@onlypreamble\DeclareErrorFont
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\wrong@fontshape}
% Before we come to the macro |\extract@font| we have to take
% care of unknown |\curr@fontshape| combinations.
% The general strategy is to issue a warning and to try a default
% \emph{shape}, then a default \emph{series},
% and finally a default \emph{family}.
% If this last one also fails \TeX{} will go into an infinite loop.
% But if the defaults are set incorrectly one deserves nothing else!
% \changes{v1.9a}{1992/07/26}{}
% \begin{macrocode}
%</2ekernel>
%<latexrelease>\IncludeInRelease{2015/01/01}{\wrong@fontshape}%
%<latexrelease> {Font substitution in preamble}%
%<*2ekernel|latexrelease>
\def\wrong@fontshape{%
\csname D@\f@encoding\endcsname % install defaults if in math
% \end{macrocode}
% We remember the wanted |\curr@fontshape| combination
% which we will need in a moment.
% \begin{macrocode}
\edef\reserved@a{\csname\curr@fontshape\endcsname}%
\ifx\last@fontshape\reserved@a
\errmessage{Corrupted NFSS tables}%
\error@fontshape
\else
% \end{macrocode}
% Then we warn the user about the mess and set the shape to its
% default.
% \changes{v1.0q}{1989/11/19}
% {Instead of calling \cs{family}\cs{default@family},
% etc. we directly set \cs{f@family}, etc.}
% \changes{v1.2f}{1990/01/28}{Warning message slightly changed.}
% \begin{macrocode}
\let\f@shape\default@shape
% \end{macrocode}
% If the combination is not known, try the default \emph{series}.
% \begin{macrocode}
\expandafter\ifx\csname\curr@fontshape\endcsname\relax
\let\f@series\default@series
% \end{macrocode}
% If this is still undefined, try the default \emph{family}.
% Otherwise give up. We never try to change the encoding scheme!
% \changes{v1.9a}{1992/07/26}{}
% \changes{v3.1a}{2015/04/07}{Try loading fd file if family has changed}
% \begin{macrocode}
\expandafter
\ifx\csname\curr@fontshape\endcsname\relax
\let\f@family\default@family
% \end{macrocode}
% If we change the font family and we are in the preamble then the
% corresponding \texttt{.fd} file may not been loaded
% yet. Therefore we try this now. Otherwise equating the requested
% font shape with the finally selected fontshape below will fail
% and can result in ``NFSS tables corrupted''. After begin document
% that will not happen as all \texttt{.fd} files involved in
% substitution are loaded at |\begin{document}|.
% \begin{macrocode}
\begingroup
\try@load@fontshape
\endgroup
\fi \fi
\fi
% \end{macrocode}
% At this point a valid |\curr@fontshape| combination must
% have been found.
% We inform the user about this fact.
%\changes{v3.0n}{1995/11/02}
% {(DPC) Remove extra space with \cs{string} for latex/1676}
% \changes{v3.0m}{1995/11/17}
% {Support \cs{@wrong@font@char} latex/1676}
%
% The |\expandafter\string| here stops \TeX\ adding the space
% that it usually puts after command names in messages. The similar
% construction with |\@undefined| just produces `undefined', but saves
% a few tokens.
%
% |\@wrong@font@char| is locally redefined in |\UseTextSymbol| from
% its normal (empty) definition, to report the symbol generating the
% font switch.
% \begin{macrocode}
\@font@warning{Font shape `\expandafter\string\reserved@a'
\expandafter\@gobble\string\@undefined\MessageBreak
using `\curr@fontshape' instead\@wrong@font@char}%
\global\let\last@fontshape\reserved@a
% \end{macrocode}
% We change |\@defaultsubs| to produce a warning at the end of
% the document.
% \changes{v3.0d}{1995/07/13}{Change a macro not a switch to flag
% default font substitutions}
% \changes{v3.0k}{1995/10/24}{Make this code inline since it
% happens only here}
% The macro |\@defaultsubs| is initially |\relax| but gets changed
% here if some default font substitution happens.
% It is then executed in |\enddocument|.
% \begin{macrocode}
\gdef\@defaultsubs{%
\@font@warning{Some font shapes were not available, defaults
substituted.\@gobbletwo}}%
% \end{macrocode}
% If we substitute a |\curr@fontshape| combination
% by the default one we don't want the warning to be printed out
% whenever this (unknown) combination is used.
% Therefore we globally |\let| the macro corresponding to
% the wanted combination equal to its substitution.
% This requires the use of four |\expandafter|'s
% since |\csname|\dots|\endcsname| has to be
% expanded before |\reserved@a| (i.e.\ the requested
% combination),
% and this must happen before the |\let| is executed.
% \begin{macrocode}
\global\expandafter\expandafter\expandafter\let
\expandafter\reserved@a
\csname\curr@fontshape\endcsname
% \end{macrocode}
% Now we can redefine |\font@name| accordingly.
% This \emph{must} be done globally since it might occur in the
% group opened by |\define@newfont|. If we would this
% definition were local the closing |\endgroup| there
% would restore the old meaning of |\font@name| and then
% switch to the wrong font at the end of |\selectfont|
% although the correct font was loaded.
% \begin{macrocode}
\xdef\font@name{%
\csname\curr@fontshape/\f@size\endcsname}%
% \end{macrocode}
% The last thing this macro does is to call |\pickup@font|
% again to load the font if it is not defined yet.
% At this point this code will loop endlessly if
% the defaults are not well defined.
% \begin{macrocode}
\pickup@font}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}{\wrong@fontshape}%
%<latexrelease> {Font substitution in preamble}%
%<latexrelease>\def\wrong@fontshape{%
%<latexrelease> \csname D@\f@encoding\endcsname
%<latexrelease> \edef\reserved@a{\csname\curr@fontshape\endcsname}%
%<latexrelease> \ifx\last@fontshape\reserved@a
%<latexrelease> \errmessage{Corrupted NFSS tables}%
%<latexrelease> \error@fontshape
%<latexrelease> \else
%<latexrelease> \let\f@shape\default@shape
%<latexrelease> \expandafter\ifx\csname\curr@fontshape\endcsname\relax
%<latexrelease> \let\f@series\default@series
%<latexrelease> \expandafter
%<latexrelease> \ifx\csname\curr@fontshape\endcsname\relax
%<latexrelease> \let\f@family\default@family
%<latexrelease> \fi \fi
%<latexrelease> \fi
%<latexrelease> \@font@warning{Font shape
%<latexrelease> `\expandafter\string\reserved@a'
%<latexrelease> \expandafter\@gobble\string\@undefined
%<latexrelease> \MessageBreak
%<latexrelease> using `\curr@fontshape' instead\@wrong@font@char}%
%<latexrelease> \global\let\last@fontshape\reserved@a
%<latexrelease> \gdef\@defaultsubs{%
%<latexrelease> \@font@warning{Some font shapes were not available,
%<latexrelease> defaults substituted.\@gobbletwo}}%
%<latexrelease> \global\expandafter\expandafter\expandafter\let
%<latexrelease> \expandafter\reserved@a
%<latexrelease> \csname\curr@fontshape\endcsname
%<latexrelease> \xdef\font@name{%
%<latexrelease> \csname\curr@fontshape/\f@size\endcsname}%
%<latexrelease> \pickup@font}
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@wrong@font@char}
% \changes{v3.0m}{1995/11/17}{(DPC) Macro added. latex/1676}
% Normally empty but redefined in |\UseTextSymbol| so that the
% Font shape undefined message can refer to the symbol causing the
% problem.
% \begin{macrocode}
\let\@wrong@font@char\@empty
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@defaultsubs}
% \changes{v3.0d}{1995/07/13}{macro added}
% \changes{v3.0k}{1995/10/24}{macro removed}
% \begin{macro}{\@defaultsubs}
% \changes{v3.0d}{1995/07/13}{macro added}
% See above.
% \begin{macrocode}
\let\@defaultsubs\relax
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\strip@prefix}
% In |\extract@font| we will need a way to recover the
% replacement text of a macro.
% This is done by the primitive |\meaning| together
% with the macro |\strip@prefix| (for the details
% see appendix~D of the \TeX{}book, p.\ 382).
% \begin{macrocode}
\def\strip@prefix#1>{}
% \end{macrocode}
% \end{macro}
%
% ^^A \extract@font
%
%
%
% \section{Assigning math fonts to \emph{versions}}
%
%
% \begin{macro}{\install@mathalphabet}
% This is just another name for |\gdef| but we can redefine it if
% necessary later on.
% \begin{macrocode}
\let\install@mathalphabet\gdef
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\math@fonts}
%
% \changes{v1.9a}{1992/07/26}{}
% \begin{macrocode}
\let\math@fonts\@empty
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\select@group}
% \changes{v1.0t}{1989/11/26}{\cs{bgroup}/\cs{egroup} changed to
% \cs{begingroup}/\cs{endgroup} to avoid empty Ord atom on math list.}
% |\select@group| has four arguments: the new
% \meta{math alphabet identifier} (a control sequence), the
% \meta{math group number}, the extra macro for math mode
% and the |\curr@fontshape| definition macro name.
% We first check if we are in math mode.
% \changes{v1.1a}{1989/12/16}{\cs{relax} in front added.}
% \changes{v1.1a}{1989/12/16}{Now four arguments.}
% \begin{macrocode}
%\def\select@group#1#2#3{\relax\ifmmode
% \end{macrocode}
% We do these things locally using |\begingroup| instead
% of |\bgroup| to avoid the appearance of an empty Ord
% atom on the math list.
% \begin{macrocode}
% \begingroup
% \end{macrocode}
% We set the math fonts for the \emph{family} in question by calling
% |\getanddefine@fonts| in the correct environment.
% \changes{v1.9a}{1992/07/26}{}
% \begin{macrocode}
% \escapechar\m@ne
% \getanddefine@fonts{\csname c@mv@\math@version\endcsname}#3%
% \end{macrocode}
% We globally select the math fonts\dots
% \begin{macrocode}
% \globaldefs\@ne \math@fonts
% \end{macrocode}
% \dots{} and close the group to
% restore |\globaldefs| and |\escapechar|.
% \begin{macrocode}
% \endgroup
% \end{macrocode}
% As long as no \emph{size} or \emph{version} change occurs
% the \meta{math alphabet identifier} should simply switch to the
% installed \emph{math group} instead of calling
% |\select@group|
% unnecessarily. So we globally redefine the first argument
% (the new \meta{math alphabet identifier})
% to expand into a |\mathgroup| switch
% and then select this \emph{alphabet}. Note that this redefinition
% will be overwritten by the next call to a \emph{version} macro.
% \changes{v1.1a}{1989/12/16}{Usage of `\quotechar=' macro added.}
% \changes{v1.1a}{1989/12/16}{Redefinition of alphabet now simpler.}
% \changes{v1.2a}{1990/01/20}{Def for alph id changed.}
% The original code for the end of |\select@group| was
% \begin{verbatim}
% \gdef#1{#3\mathgroup #2}#1\fi}
%\end{verbatim}
% i.e.\ first redefining the \meta{math alphabet identifier} and
% then calling the new definition to switch to the wanted
% \meta{math group}. Now we define the \meta{math alphabet
% identifier} as a call to the |\use@mathgroup| command.
% \changes{v1.2b}{1990/01/21}{Code moved to \cs{use@mathgroup}.}
% \begin{macrocode}
% \xdef#1{\noexpand\use@mathgroup\noexpand#2%
% {\number\csname c@mv@\math@version\endcsname}}%
% \end{macrocode}
% \changes{v1.3c}{1992/05/12}{Added call to
% \cs{extract@alph@from@version}.}
% But this is not sufficient, as we learned the hard way.
% The problem here is that the loading of the fonts that comprise
% the alphabet identifier |#1|, as well as the necessary math font
% assignments is deferred until it is used. This is OK so far, but
% if the fonts are switched within the current formula (which may
% happen if a sub-formula is a box that contains a math version
% switch) the font assignments for |#1| are not restored unless
% |#1| is used again. This is disastrous since TeX sees the wrong
% fonts at the end of the math formula, when it converts the math
% list into a horizontal list.
%
% This is taken into account as follows: When a math alphabet
% identifier is used for the first time in a certain version
% it modifies the corresponding macro |\mv@|\meta{version}
% so that it calls |\getanddefine@fonts| directly in future as well.
% We use the macro |\extract@alph@from@version| to do this.
% It takes the math alphabet identifier |#1| and the math version
% macro as arguments.
% \changes{v1.9a}{1992/07/26}{}
% \begin{macrocode}
% \expandafter\extract@alph@from@version
% \csname mv@\math@version\expandafter\endcsname
% \expandafter{\number\csname c@mv@\math@version\endcsname}%
% #1%
% \stepcounter{mv@\math@version}%
% \end{macrocode}
% Finally, it is not possible to simply call the new definition
% since we
% have an argument (the third argument of |\use@mathgroup|
% or more exactly the argument of |\math@egroup| if the {\ttfamily
% margid} option is in force)
% which would swallow our closing |\fi|. So
% we use the |\expandafter| technique to remove the |\fi|
% before the |\use@mathgroup| is expanded.
% \begin{macrocode}
%\expandafter #1\fi}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\extract@alph@from@version}
% \changes{v1.3c}{1992/05/12}{Macro added.}
% We proceed to the definition of the
% macro |\extract@alph@from@version|. As stated above, it takes
% a math alphabet identifier and a math version macro
% (e.g.\ |\mv@normal|) as its arguments.
% \begin{macrocode}
\def\extract@alph@from@version#1#2#3{%
% \end{macrocode}
% To extract and replace the definition of math alphabet identifier
% |#3| in macro |#1| we have to recall how this definition looks
% like: Somewhere in the replacement text of |#1| there is
% the sequence\\[2pt]
% |\install@mathalphabet|\meta{math alphabet identifier} |#3||{%| \\
% \hspace*{\MacroIndent}\hspace*{5mm}
% \meta{Definitions for }|#3}| \\[2pt]
% Hence, the first thing we do is to extract the tokens preceding
% this definitions, the definition itself, and the tokens following
% it. To this end we define one auxiliary macro |\reserved@a|.
% \begin{macrocode}
\def\reserved@a##1\install@mathalphabet#3##2##3\@nil{%
% \end{macrocode}
% When |\reserved@a| is expanded, it will have the tokens preceding
% the definition in question in its first argument (|##1|), the
% following tokens in its third argument (|##3|), and the replacement
% text for the math alphabet identifier |#3| in its second argument.
% (|##2|). This is then recorded for later use in a temporary macro
% |\reserved@b|.
% \begin{macrocode}
\def\reserved@b{##2}%
% \end{macrocode}
% Additionally, we define a macro |\reserved@c| to reconstruct the
% definitions for the math version in question from the tokens that
% will remain unchanged (|##1| and |##3|) and the yet to build new
% definitions for the math alphabet identifier |#3|.
% \begin{macrocode}
\def\reserved@c####1{\gdef#1{##1####1##3}}}%
% \end{macrocode}
% Then we execute our auxiliary macro.
% \begin{macrocode}
\expandafter\reserved@a#1\@nil
% \end{macrocode}
% OK, so now we have to build the new definition for |#3|. To do so,
% we first extract the interesting parts out of the old one.
% The old definition looks like:\\[2pt]
% |\select@group|\meta{math alphabet identifier} \\
% \hspace*{\MacroIndent}\hspace*{5mm}
% \meta{math group number}\meta{math extra part}\\
% \meta{|curr@fontshape| definition} \\[2pt]
% So we define a new temporary macro |\reserved@a| that
% extracts these parts.
% \begin{macrocode}
\def\reserved@a\select@group#3##1##2\@nil{%
% \end{macrocode}
% This macro can now directly rebuild the math version definition
% by calling |\reserved@c|:
% \begin{macrocode}
\reserved@c{%
\getanddefine@fonts{#2}##2%
\install@mathalphabet#3{%
\relax\ifmmode \else \non@alpherr#3\fi
\use@mathgroup##1{#2}}}%
% \end{macrocode}
% \changes{v2.1t}{1994/10/15}{Warn if math alpha is used outside math}
% In addition it defines the alphabet the way it should be used from
% now on.
% \begin{macrocode}
\gdef#3{\relax\ifmmode \else \non@alpherr#3\fi
\use@mathgroup##1{#2}}}%
% \end{macrocode}
% Finally, we only have to call this macro |\reserved@a| on the old
% definitions recorded in |\reserved@b|:
% \begin{macrocode}
\expandafter\reserved@a\reserved@b\@nil
}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\math@bgroup}
% \changes{v1.2a}{1990/01/20}{Def. placed in this file.}
% \begin{macro}{\math@egroup}
% \changes{v1.2a}{1990/01/20}{Def. placed in this file.}
% \changes{v1.2h}{1990/03/30}{Changed to have one arg.}
% \changes{v2.2f}{1994/03/10}{Changed \cs{begingroup}/\cs{endgroup} to
% \cs{bgroup}/\cs{egroup}.}
% Here are the default definitions for |\math@bgroup| and
% |\math@egroup|. We use |\bgroup| instead of |\begingroup|
% to avoid `leaking out' of style changes. This has the side
% effect of always producing mathord atoms.
% \begin{macrocode}
\let\math@bgroup\bgroup
\def\math@egroup#1{#1\egroup}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\calculate@math@sizes}
% \changes{v2.1i}{1994/04/18}{Changed message to log only}
% Here is the default definition for |\calculate@math@sizes|
% a more elaborate interface
% is under testing in mthscale.sty.
% \begin{macrocode}
\gdef\calculate@math@sizes{%
\@font@info{Calculating\space math\space sizes\space for\space
size\space <\f@size>}%
\dimen@\f@size \p@
\@tempdimb \defaultscriptratio \dimen@
\dimen@ \defaultscriptscriptratio \dimen@
\expandafter\xdef\csname S@\f@size\endcsname{%
\gdef\noexpand\tf@size{\f@size}%
\gdef\noexpand\sf@size{\strip@pt\@tempdimb}%
\gdef\noexpand\ssf@size{\strip@pt\dimen@}%
\noexpand\math@fontstrue}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\defaultscriptratio}
% \changes{v2.1h}{1994/04/11}{Macro added}
% \begin{macro}{\defaultscriptscriptratio}
% \changes{v2.1h}{1994/04/11}{Macro added}
% The default ratio for math
% sizes is:\\
% 1 to |\defaultscriptratio| to |\defaultscriptscriptratio|.\\
% By default this is 1 to .7 to .5.
% \begin{macrocode}
\def\defaultscriptratio{.7}
\def\defaultscriptscriptratio{.5}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\noaccents@}
% If we don't have a definition for |\noaccents@| we provide a
% dummy.
% \begin{macrocode}
\ifx\noaccents@\@undefined
\let\noaccents@\@empty
\fi
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\showhyphens}
% \changes{v1.2l}{1990/06/30}{Macro added.}
% \changes{v2.0e}{1993/05/16}{Use \cs{reset@font}}
% \changes{v3.0h}{1995/10/10}
% {Use \cs{normalfont} and make colour safe, and autoloadable}
% \changes{v3.0u}{1998/03/25}
% {Suppress unnecessary error when used in preamble}
% \changes{v3.2a}{2017/01/10}
% {Add version of \cs{showhyphens} that works with Xe\TeX.}
% The |\showhyphens| command must be redefined since the version in
% \texttt{plain.tex} uses |\tenrm|. We have also made some further
% adjustments for its use in \LaTeX.
% \begin{macrocode}
%</2ekernel>
%<latexrelease>\IncludeInRelease{2017/01/01}{\showhyphens}%
%<latexrelease> {XeTeX support for \showhyphens}%
%<*2ekernel|latexrelease>
\ifx\XeTeXcharclass\@undefined
% \end{macrocode}
% Version for engines other than Xe\TeX.
% \begin{macrocode}
\DeclareRobustCommand\showhyphens[1]{%
\setbox0\vbox{%
\color@begingroup
\everypar{}%
\parfillskip\z@skip\hsize\maxdimen
\normalfont
\pretolerance\m@ne\tolerance\m@ne\hbadness\z@\showboxdepth\z@\ #1%
\color@endgroup}}
% \end{macrocode}
% \begin{macrocode}
\else
% \end{macrocode}
% Xe\TeX\ version. When using system fonts Xe\TeX\ reports consecutive
% runs of characters as a single item in box logging, which means the
% standard |\showhyphens| does not work. This version typesets the
% text into a narrow box to force hyphenation and then reconstructs a
% horizontal list with explicit hyphens to generate the display. Note
% that the |lmr| OpenType font is forced, this works even if the
% characters are not in the font as hyphenation is attempted due to
% the width of the space and hyphen character. It may generate
% spurious Missing Character warnings in the log, these are however
% suppressed from the terminal output by ensuring that
% |\tracingonline| is locally zero.
% \begin{macrocode}
\DeclareRobustCommand\showhyphens[1]{%
\setbox0\vbox{%
\usefont{TU}{lmr}{m}{n}%
\hsize 1sp %
\hbadness\@M
\hfuzz\maxdimen
\tracingonline\z@
\everypar={}%
\leftskip\z@skip
\rightskip\z@skip
\parfillskip\z@skip
\hyphenpenalty=-\@M
\pretolerance\m@ne
\interlinepenalty\z@
\clubpenalty\z@
\widowpenalty\z@
\brokenpenalty1127 %
\setbox\z@\hbox{}%
\noindent
\hskip\z@skip
#1%
\par
% \end{macrocode}
% Note here we stop the loop if made no progress, non-removable items
% may mean that we can not process the whole list (which would be
% testable as |\lastnodetype=-1|).
% \begin{macrocode}
\loop
\@tempswafalse
\ifnum\lastnodetype=11\unskip\@tempswatrue\fi
\ifnum\lastnodetype=12\unkern\@tempswatrue\fi
\ifnum\lastnodetype=13 %
\count@\lastpenalty
\unpenalty\@tempswatrue
\fi
\ifnum\lastnodetype=\@ne
\setbox\tw@\lastbox\@tempswatrue
\setbox0\hbox{\unhbox\tw@\unskip\unskip\unpenalty
\ifnum\count@=1127 \else\ \fi
\unhbox0}%
\count@\z@
\fi
\if@tempswa
\repeat
\hbadness\z@
\hsize\maxdimen
\showboxdepth\z@
\tolerance\m@ne
\hyphenpenalty\z@
\noindent\unhbox\z@
}}
% \end{macrocode}
%
% \begin{macrocode}
\fi
% \end{macrocode}
%
% \begin{macrocode}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}{\showhyphens}%
%<latexrelease> {XeTeX support for \showhyphens}%
%<latexrelease>\gdef\showhyphens#1{%
%<latexrelease> \setbox0\vbox{%
%<latexrelease> \color@begingroup
%<latexrelease> \everypar{}%
%<latexrelease> \parfillskip\z@skip\hsize\maxdimen
%<latexrelease> \normalfont
%<latexrelease> \pretolerance\m@ne\tolerance\m@ne
%<latexrelease> \hbadness\z@\showboxdepth\z@\ #1%
%<latexrelease> \color@endgroup}}
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\addto@hook}
% \changes{v1.0u}{1989/12/05}{\cs{addto@hook} added.}
% \changes{v2.1d}{1994/02/10}{Made \cs{addto@hook} long.}
% We need a macro to add tokens to a hook.
% \begin{macrocode}
\long\def\addto@hook#1#2{#1\expandafter{\the#1#2}}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\@vpt}
% \changes{v2.1v}{1994/11/09}{(DPC) macros added, from setsize.dtx}
% \changes{v2.1v}{1994/11/09}{(DPC) reduce save stack usage latex/1742}
% \begin{macrocode}
\def\@vpt{5}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@vipt}
% \begin{macrocode}
\def\@vipt{6}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@viipt}
% \begin{macrocode}
\def\@viipt{7}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@viiipt}
% \begin{macrocode}
\def\@viiipt{8}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@ixpt}
% \begin{macrocode}
\def\@ixpt{9}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@xpt}
% \begin{macrocode}
\def\@xpt{10}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@xipt}
% \begin{macrocode}
\def\@xipt{10.95}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@xiipt}
% \begin{macrocode}
\def\@xiipt{12}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@xivpt}
% \begin{macrocode}
\def\@xivpt{14.4}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@xviipt}
% \begin{macrocode}
\def\@xviipt{17.28}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@xxpt}
% \begin{macrocode}
\def\@xxpt{20.74}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@xxvpt}
% \begin{macrocode}
\def\@xxvpt{24.88}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</2ekernel>
% \end{macrocode}
%
% \Finale
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\endinput
^^A Needed for emacs
^^A
^^A Local Variables:
^^A mode: latex
^^A coding: utf-8-unix
^^A End:
