diff options
Diffstat (limited to 'macros/latex/base/ltexpl.dtx')
-rw-r--r-- | macros/latex/base/ltexpl.dtx | 261 |
1 files changed, 236 insertions, 25 deletions
diff --git a/macros/latex/base/ltexpl.dtx b/macros/latex/base/ltexpl.dtx index 230cd91158..4100da79c2 100644 --- a/macros/latex/base/ltexpl.dtx +++ b/macros/latex/base/ltexpl.dtx @@ -33,67 +33,278 @@ %<*driver> % \fi \ProvidesFile{ltexpl.dtx} - [2019-10-02 v0.0 LaTeX Kernel (expl3-dependent code)] + [2020/09/06 v1.2f LaTeX Kernel (expl3-dependent code)] % \iffalse \documentclass{ltxdoc} -\GetFileInfo{ltfinal.dtx} +\GetFileInfo{ltexpl.dtx} \title{\filename} \date{\filedate} \author{% Joseph Wright} + +\providecommand\pkg[1]{\texttt{#1}} + \begin{document} \MaintainedByLaTeXTeam{latex} \maketitle - \DocInput{ltfinal.dtx} + \DocInput{ltexpl.dtx} \end{document} %</driver> % \fi % +% +% \changes{v1.2d}{2020/08/21}{Dropped unused command} +% % \section{\pkg{expl3}-dependent code} % % \StopEventually{} % % \changes{v0.0}{2019-10-02}{Initial version} % +% \subsection{Loader} +% +% \changes{v1.0a}{2020/03/02} +% {Don't load expl3 if already in the format (gh/295)} +% \changes{v1.1}{2020/03/05} +% {Load xparse.ltx if \cs{NewDocumentCommand} is not defined +% by expl3.ltx} +% \changes{v1.2c}{2020/06/04} +% {Define a local version of some \LaTeXe{} basic macros to support +% package loading} +% +% First define some blank commands, so that in case something goes wrong while +% loading \textsf{expl3}, we won't get strange \texttt{Undefined control +% sequence} errors. % \begin{macrocode} %<*2ekernel> +\def\@expl@sys@load@backend@@{} +\def\@expl@push@filename@@{} +\def\@expl@push@filename@aux@@{} +\def\@expl@pop@filename@@{} +%</2ekernel> % \end{macrocode} % -% \subsection{Loader} +% \changes{v1.2d}{2020/07/08} +% {Add a last-minute hook for \textsf{expl3}} +% Create a hook for last-minute \pkg{expl3} material. +% \begin{macrocode} +%<*2ekernel> +\def\@expl@finalise@setup@@{} +%</2ekernel> +% \end{macrocode} +% +% Now define some basics to support loading \textsf{expl3}. These macros can +% be defined here safely, because they are redefined later on by the kernel, +% so we define simpler versions just to suit our needs. +% \begin{macrocode} +%<*2ekernel> +\long\def\@gobble#1{} +\long\def\@firstofone#1{#1} +\long\def\@firstoftwo#1#2{#1} +\long\def\@secondoftwo#1#2{#2} +\long\def\IfFileExists#1{% + \openin\@inputcheck"#1" % + \ifeof\@inputcheck + \expandafter\@secondoftwo + \else + \closein\@inputcheck + \expandafter\@firstoftwo + \fi} +\long\def\@ifnextchar#1#2#3{% + \let\reserved@d=#1% + \def\reserved@a{#2}% + \def\reserved@b{#3}% + \futurelet\@let@token\@ifnch} +\def\@ifnch{% + \ifx\@let@token\reserved@d + \expandafter\reserved@a + \else + \expandafter\reserved@b + \fi} +%</2ekernel> +% \end{macrocode} +% +% If we are doing a rollback with a format containing expl3 we +% aren't reloading it as that creates havoc. This may need a +% refined version! +% \begin{macrocode} +%<*2ekernel|latexrelease> +%<latexrelease>\IncludeInRelease{2020/10/01}% +%<latexrelease> {expl3}{Pre-load expl3}% +\expandafter\ifx\csname tex\string _let:D\endcsname\relax + \expandafter\@firstofone +\else + \GenericInfo{}{Skipping: expl3 code already part of the format}% +%<2ekernel> \expandafter\endinput +%<latexrelease> \expandafter\@gobble +\fi +% \end{macrocode} % % Check for the required primitive/engine support and the existence of % a loader. % \begin{macrocode} + {% + \IfFileExists{expl3.ltx} + {% + \ifnum0% + \ifdefined\pdffilesize 1\fi + \ifdefined\filesize 1\fi + \ifdefined\luatexversion\ifnum\luatexversion>94 1\fi\fi + \ifdefined\kanjiskip 1\fi + >0 % + \expandafter\@firstofone + \else +% \end{macrocode} +% +% In \texttt{2ekernel} mode, an error is fatal and building the format +% is aborted. Use \verb=\batchmode \read -1 to \tokenlist=, which errors +% with +% \verb=! Emergency stop. (cannot \read from terminal in nonstop modes)= +% and aborts the \TeX{} run. In \texttt{latexrelease} mode, raise an +% error and do nothing. Both ways, the error message shows the minimum +% \textsf{expl3} engine requirements. +% \begin{macrocode} +%<2ekernel> \def~{ }\def\MessageBreak{^^J~~~~~~~~~~~~~~~}% +%<2ekernel> \errmessage{LaTeX Error: +%<latexrelease> \@latex@error{% + LaTeX requires the e-TeX primitives and additional\MessageBreak + functionality available in the engines:\MessageBreak + - pdfTeX v1.40\MessageBreak + - XeTeX v0.99992\MessageBreak + - LuaTeX v0.95\MessageBreak + - e-(u)pTeX mid-2012\MessageBreak + or later% +%<latexrelease> }\@ehd \expandafter\@gobble +%<2ekernel> }\batchmode \read -1 to \reserved@a + \fi + } + {% +%<*2ekernel> + \errmessage{LaTeX requires expl3}% + \batchmode \read -1 to \reserved@a %</2ekernel> -%<*2ekernel|latexrelease> +%<*latexrelease> + \@latex@error{LaTeX requires expl3}\@ehd + \@gobble +%</latexrelease> + }% + {% + \input expl3.ltx + \ifdefined\NewDocumentCommand + \else + \IfFileExists{xparse.ltx} + {\input xparse.ltx } + {}% + \fi + }% + } +%<latexrelease>\EndIncludeInRelease +%<latexrelease> %<latexrelease>\IncludeInRelease{2020/02/02}% %<latexrelease> {expl3}{Pre-load expl3}% -\IfFileExists{expl3.ltx} - {% - \ifnum0% - \ifdefined\pdffilesize 1\fi - \ifdefined\filesize 1\fi - \ifdefined\luatexversion\ifnum\luatexversion>94 1\fi\fi - >0 % - \else - \message{Skipping expl3-dependent extensions} -%<2ekernel> \expandafter\endinput +%<latexrelease>\IfFileExists{expl3.ltx} +%<latexrelease> {% +%<latexrelease> \ifnum0% +%<latexrelease> \ifdefined\pdffilesize 1\fi +%<latexrelease> \ifdefined\filesize 1\fi +%<latexrelease> \ifdefined\luatexversion\ifnum\luatexversion>94 1\fi\fi +%<latexrelease> >0 % +%<latexrelease> \else +%<latexrelease> \message{Skipping expl3-dependent extensions} %<latexrelease> \expandafter\@gobbletwo - \fi - } - {% - \message{Skipping expl3-dependent extensions}% -%<2ekernel> \endinput +%<latexrelease> \fi +%<latexrelease> } +%<latexrelease> {% +%<latexrelease> \message{Skipping expl3-dependent extensions}% %<latexrelease> \@gobbletwo - }% -\input{expl3.ltx} -%</2ekernel|latexrelease> +%<latexrelease> }% +%<latexrelease>\input{expl3.ltx} %<latexrelease>\EndIncludeInRelease -%<*2ekernel> % \end{macrocode} % +% \subsection{Using expl3 code} +% +% In order to ease the implemantation of some new features in +% \LaTeXe\ we may (temporarily) use some coding based on the +% \pkg{expl3}-code. +% Such macros will eventually vanish and may be changed +% unannounced. They are there for internal use in the \LaTeXe\ +% kernel and are not meant to be used in third-party +% packages. These macros will always have the \verb|@expl@| +% prefix in their name. +% +% The rest of the name matches the \pkg{expl3} name but with all +% underscores replaced by \texttt{@}s and the \texttt{:} replaced +% by \texttt{@@}, e.g., +%\begin{verbatim} +% \cs_new_eq:NN \@expl@tl@trim@spaces@apply@@nN \tl_trim_spaces_apply:nN +%\end{verbatim} +% if that \pkg{expl3} command is needed in places that are others +% coded in \LaTeXe{} conventions. +% % \begin{macrocode} -%</2ekernel> +\ExplSyntaxOn +% \end{macrocode} +% +% In this file, each release of LaTeX adds an \cs{IncludeInRelease} +% block, in which the macros copied for that release were defined. +% In case a rollback is requested, the entire block is changed. +% +% Each macro copied has a \cs{changes} entry to explain when and why +% it was copied, so that further to that may spot it easily. +% +% Here \cs{cs\string_gset\string_eq:NN} is used, instead of the |new| +% variant because if different releases use that same name for +% different purposes, each can copy the macro without worrying about +% redefinitions. +% +% \begin{macrocode} +%<latexrelease>\IncludeInRelease{2020/10/01}{expl3~2020-10-01}% +%<latexrelease> {expl3~macros~added~for~the~2020-10-01~release}% +% \end{macrocode} +% +% \changes{v1.2e}{2020/08/19} +% {Add \cs{@expl@cs@to@str@@N} and \cs{@expl@str@if@eq@@nnTF} +% for \cs{NewCommandCopy} (gh/239)} +% \begin{macrocode} +\cs_gset_eq:NN \@expl@cs@to@str@@N \cs_to_str:N +\cs_gset_eq:NN \@expl@str@if@eq@@nnTF \str_if_eq:nnTF +% \end{macrocode} +% +% \changes{v1.2e}{2020/08/19} +% {Add \cs{@expl@cs@\meta{thing}@spec@@N} +% for \cs{ShowCommand} (gh/373)} +% \begin{macrocode} +\cs_gset_eq:NN \@expl@cs@prefix@spec@@N \cs_prefix_spec:N +\cs_gset_eq:NN \@expl@cs@argument@spec@@N \cs_argument_spec:N +\cs_gset_eq:NN \@expl@cs@replacement@spec@@N \cs_replacement_spec:N +% \end{macrocode} +% +% \changes{v1.2f}{2020/09/06} +% {Add \cs{@expl@str@map@function@@NN +% and \cs{@expl@char@generate@@nn}} +% for \cs{string@makeletter} (gh/386)} +% \begin{macrocode} +\cs_gset_eq:NN \@expl@str@map@function@@NN \str_map_function:NN +\cs_gset_eq:NN \@expl@char@generate@@nn \char_generate:nn +% \end{macrocode} +% +% \begin{macrocode} +%<latexrelease>\EndIncludeInRelease +%<latexrelease>\IncludeInRelease{0000/00/00}{expl3~2020-10-01}% +%<latexrelease> {expl3~macros~added~for~the~2020-10-01~release}% +%<latexrelease>\cs_undefine:N \@expl@cs@to@str@@N +%<latexrelease>\cs_undefine:N \@expl@str@if@eq@@nnTF +%<latexrelease>\cs_undefine:N \@expl@cs@prefix@spec@@N +%<latexrelease>\cs_undefine:N \@expl@cs@argument@spec@@N +%<latexrelease>\cs_undefine:N \@expl@cs@replacement@spec@@N +%<latexrelease>\cs_undefine:N \@expl@str@map@function@@NN +%<latexrelease>\EndIncludeInRelease +%</2ekernel|latexrelease> +% \end{macrocode} +% +% \begin{macrocode} +\ExplSyntaxOff % \end{macrocode} % % \Finale |