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|
% \iffalse meta-comment
%
%% File: l3bootstrap.dtx
%
% Copyright (C) 2011-2024 The LaTeX Project
%
% It may be distributed and/or modified under the conditions of the
% LaTeX Project Public License (LPPL), either version 1.3c of this
% license or (at your option) any later version. The latest version
% of this license is in the file
%
% https://www.latex-project.org/lppl.txt
%
% This file is part of the "l3kernel bundle" (The Work in LPPL)
% and all files in that bundle must be distributed together.
%
% -----------------------------------------------------------------------
%
% The development version of the bundle can be found at
%
% https://github.com/latex3/latex3
%
% for those people who are interested.
%
%<*driver>
\documentclass[full,kernel]{l3doc}
\begin{document}
\DocInput{\jobname.dtx}
\end{document}
%</driver>
% \fi
%
% \title{^^A
% The \pkg{l3bootstrap} module\\ Bootstrap code^^A
% }
%
% \author{^^A
% The \LaTeX{} Project\thanks
% {^^A
% E-mail:
% \href{mailto:latex-team@latex-project.org}
% {latex-team@latex-project.org}^^A
% }^^A
% }
%
% \date{Released 2024-08-30}
%
% \maketitle
%
% \begin{documentation}
%
% \section{Using the \LaTeX3 modules}
%
% The modules documented in ^^A
% \ifinterface
% this file (and \file{source3} for documented sources) ^^A
% \else
% \file{interface3} (and this file) ^^A
% \fi
% are designed to be used on top of \LaTeXe{} and are already pre-loaded
% since \LaTeXe{} 2020-02-02.
% To support older formats, the |\usepackage{expl3}| or |\RequirePackage{expl3}|
% instructions are still available to load them all as one.
%
% As the modules use a coding syntax different from standard
% \LaTeXe{} it provides a few functions for setting it up.
%
% \begin{function}[updated = 2011-08-13]{\ExplSyntaxOn, \ExplSyntaxOff}
% \begin{syntax}
% \cs{ExplSyntaxOn} \meta{code} \cs{ExplSyntaxOff}
% \end{syntax}
% The \cs{ExplSyntaxOn} function switches to a category code
% regime in which spaces and new lines are ignored, and in which the colon (|:|)
% and underscore (|_|) are treated as \enquote{letters}, thus allowing
% access to the names of code functions and variables. Within this
% environment, |~| is used to input a space. The \cs{ExplSyntaxOff}
% reverts to the document category code regime.
% \begin{texnote}
% Spaces introduced by~|~| behave much in the same way as normal
% space characters in the standard category code regime: they are
% ignored after a control word or at the start of a line, and
% multiple consecutive~|~| are equivalent to a single one. However,
% |~|~is \emph{not} ignored at the end of a line.
% \end{texnote}
% \end{function}
%
% \begin{function}[updated = 2017-03-19, updated = 2023-08-03]
% {\ProvidesExplPackage, \ProvidesExplClass, \ProvidesExplFile}
% \begin{syntax}
% \cs{ProvidesExplPackage} \Arg{package} \Arg{date} \Arg{version} \Arg{description}
% \end{syntax}
% These functions act broadly in the same way as the corresponding
% \LaTeXe{} kernel
% functions \tn{ProvidesPackage}, \tn{ProvidesClass} and
% \tn{ProvidesFile}. However, they also implicitly switch
% \cs{ExplSyntaxOn} for the remainder of the code with the file. At the
% end of the file, \cs{ExplSyntaxOff} will be called to reverse this.
% (This is the same concept as \LaTeXe{} provides in turning on
% \tn{makeatletter} within package and class code.) The \meta{date} should
% be given in the format \meta{year}/\meta{month}/\meta{day} or in the ISO
% date format \meta{year}-\meta{month}-\meta{day}. If the
% \meta{version} is given then a leading \texttt{v} is optional: if given
% as a \enquote{pure} version string, a \texttt{v} will be prepended.
% \end{function}
%
% \begin{function}[updated = 2012-06-04]{\GetIdInfo}
% \begin{syntax}
% \cs{GetIdInfo} |$Id:| \meta{SVN info field} |$| \Arg{description}
% \end{syntax}
% Extracts all information from a SVN field. Spaces are not
% ignored in these fields. The information pieces are stored in
% separate control sequences with \cs{ExplFileName} for the part of the
% file name leading up to the period, \cs{ExplFileDate} for date,
% \cs{ExplFileVersion} for version and \cs{ExplFileDescription} for the
% description.
% \end{function}
%
% To summarize: Every single package using this syntax should identify
% itself using one of the above methods. Special care is taken so that
% every package or class file loaded with \tn{RequirePackage} or similar
% are loaded with usual \LaTeXe{} category codes and the \LaTeX3 category code
% scheme is reloaded when needed afterwards. See implementation for
% details. If you use the \cs{GetIdInfo} command you can use the
% information when loading a package with
% \begin{verbatim}
% \ProvidesExplPackage{\ExplFileName}
% {\ExplFileDate}{\ExplFileVersion}{\ExplFileDescription}
% \end{verbatim}
%
% \end{documentation}
%
% \begin{implementation}
%
% \section{\pkg{l3bootstrap} implementation}
%
% \begin{macrocode}
%<*package>
%<@@=kernel>
% \end{macrocode}
%
% \subsection{The \tn{pdfstrcmp} primitive in \XeTeX{}}
%
% Only \pdfTeX{} has a primitive called \tn{pdfstrcmp}. The \XeTeX{}
% version is just \tn{strcmp}, so there is some shuffling to do. As
% this is still a real primitive, using the \pdfTeX{} name is \enquote{safe}.
% \begin{macrocode}
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname pdfstrcmp\endcsname\relax
\let\pdfstrcmp\strcmp
\fi
% \end{macrocode}
%
% \subsection{Loading support \Lua{} code}
%
% When \LuaTeX{} is used there are various pieces of \Lua{} code which need to
% be loaded. The code itself is defined in \pkg{l3luatex} and is extracted into
% a separate file. Thus here the task is to load the \Lua{} code both now and
% (if required) at the start of each job.
% \begin{macrocode}
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname directlua\endcsname\relax
\else
\ifnum\luatexversion<110 %
\else
% \end{macrocode}
% For \LuaTeX{} we make sure the basic support is loaded:
% this is only necessary in plain.
% \begin{macrocode}
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname newcatcodetable\endcsname\relax
\input{ltluatex}%
\fi
\begingroup\expandafter\expandafter\expandafter\endgroup
\expandafter\ifx\csname newluabytecode\endcsname\relax
\else
\newluabytecode\@expl@luadata@bytecode
\fi
\directlua{require("expl3")}%
% \end{macrocode}
% As the user might be making a custom format, no assumption is made about
% matching package mode with only loading the \Lua{} code once. Instead, a
% query to \Lua{} reveals what mode is in operation.
% \begin{macrocode}
\ifnum 0%
\directlua{
if status.ini_version then
tex.write("1")
end
}>0 %
\everyjob\expandafter{%
\the\expandafter\everyjob
\csname\detokenize{lua_now:n}\endcsname{require("expl3")}%
}%
\fi
\fi
\fi
% \end{macrocode}
%
% \subsection{Engine requirements}
%
% The code currently requires \eTeX{}, the set of \enquote{\pdfTeX{}
% extensions} \emph{including} \tn{expanded}, and for Unicode engines the
% ability to generate arbitrary character tokens by expansion. That is covered
% by all supported engines since \TeX{} Live 2019, which we therefore use
% as a baseline for engine and \LaTeX{} format support.
% For \LuaTeX, we require at least Lua 5.3 and the |token.set_lua| function.
% This is available at least since \LuaTeX{} 1.10, which again is the one
% in \TeX{} Live 2019. (u)p\TeX{} only gained \tn{ifincsname} for \TeX{}
% Live 2020, but at present that primitive is unused in \pkg{expl3} so for
% the present it's not tested. If and when that changes, we will need to
% revisit the code here.
% \begin{macrocode}
\begingroup
\def\next{\endgroup}%
\def\ShortText{Required primitives not found}%
\def\LongText%
{%
The L3 programming layer requires the e-TeX primitives and the
\LineBreak 'pdfTeX utilities' as described in the README file.
\LineBreak
These are available in the engines\LineBreak
- pdfTeX v1.40.20\LineBreak
- XeTeX v0.999991\LineBreak
- LuaTeX v1.10\LineBreak
- e-(u)pTeX v3.8.2\LineBreak
- Prote (2021)\LineBreak
or later.\LineBreak
\LineBreak
}%
\ifnum0%
\expandafter\ifx\csname luatexversion\endcsname\relax
\expandafter\ifx\csname expanded\endcsname\relax\else 1\fi
\else
\ifnum\luatexversion<110 \else 1\fi
\fi
=0 %
\newlinechar`\^^J %
\def\LineBreak{\noexpand\MessageBreak}%
\expandafter\ifx\csname PackageError\endcsname\relax
\def\LineBreak{^^J}%
\begingroup
\lccode`\~=`\ \lccode`\}=`\ %
\lccode`\T=`\T\lccode`\H=`\H%
\catcode`\ =11 %
\lowercase{\endgroup\def\PackageError#1#2#3{%
\begingroup\errorcontextlines-1\immediate\write0{}\errhelp{#3}\def%
\ {#1 Error: #2.^^J^^J
Type H <return> for immediate help}\def~{\errmessage{%
\ }}~\endgroup}}%
\fi
\edef\next
{%
\noexpand\PackageError{expl3}{\ShortText}
{\LongText Loading of expl3 will abort!}%
\endgroup
\noexpand\endinput
}%
\fi
\next
% \end{macrocode}
%
% \subsection{The \LaTeX3 code environment}
%
% The code environment is now set up.
%
% \begin{macro}{\ExplSyntaxOff}
% Before changing any category codes, in package mode we need to save
% the situation before loading. Note the set up here means that once applied
% \cs{ExplSyntaxOff} becomes a \enquote{do nothing} command until
% \cs{ExplSyntaxOn} is used.
% \begin{macrocode}
\protected\edef\ExplSyntaxOff
{%
\protected\def\noexpand\ExplSyntaxOff{}%
\catcode 9 = \the\catcode 9\relax
\catcode 32 = \the\catcode 32\relax
\catcode 34 = \the\catcode 34\relax
\catcode 58 = \the\catcode 58\relax
\catcode 94 = \the\catcode 94\relax
\catcode 95 = \the\catcode 95\relax
\catcode 124 = \the\catcode 124\relax
\catcode 126 = \the\catcode 126\relax
\endlinechar = \the\endlinechar\relax
\chardef\csname\detokenize{l_@@_expl_bool}\endcsname = 0\relax
}%
% \end{macrocode}
% \end{macro}
%
% The code environment is now set up.
% \begin{macrocode}
\catcode 9 = 9\relax
\catcode 32 = 9\relax
\catcode 34 = 12\relax
\catcode 58 = 11\relax
\catcode 94 = 7\relax
\catcode 95 = 11\relax
\catcode 124 = 12\relax
\catcode 126 = 10\relax
\endlinechar = 32\relax
% \end{macrocode}
%
% \begin{variable}{\l_@@_expl_bool}
% The status for code syntax: this is on at present.
% \begin{macrocode}
\global\chardef\l_@@_expl_bool = 1\relax
% \end{macrocode}
%\end{variable}
%
% \begin{macro}{\ExplSyntaxOn}
% The idea here is that multiple \cs{ExplSyntaxOn} calls are not
% going to mess up category codes, and that multiple calls to
% \cs{ExplSyntaxOff} are also not wasting time. Applying
% \cs{ExplSyntaxOn} alters the definition of \cs{ExplSyntaxOff}
% and so in package mode this function should not be used until after
% the end of the loading process!
% \begin{macrocode}
\protected \def \ExplSyntaxOn
{
\bool_if:NF \l_@@_expl_bool
{
\cs_set_protected:Npe \ExplSyntaxOff
{
\char_set_catcode:nn { 9 } { \char_value_catcode:n { 9 } }
\char_set_catcode:nn { 32 } { \char_value_catcode:n { 32 } }
\char_set_catcode:nn { 34 } { \char_value_catcode:n { 34 } }
\char_set_catcode:nn { 58 } { \char_value_catcode:n { 58 } }
\char_set_catcode:nn { 94 } { \char_value_catcode:n { 94 } }
\char_set_catcode:nn { 95 } { \char_value_catcode:n { 95 } }
\char_set_catcode:nn { 124 } { \char_value_catcode:n { 124 } }
\char_set_catcode:nn { 126 } { \char_value_catcode:n { 126 } }
\tex_endlinechar:D =
\tex_the:D \tex_endlinechar:D \scan_stop:
\bool_set_false:N \l_@@_expl_bool
\cs_set_protected:Npn \ExplSyntaxOff { }
}
}
\char_set_catcode_ignore:n { 9 } % tab
\char_set_catcode_ignore:n { 32 } % space
\char_set_catcode_other:n { 34 } % double quote
\char_set_catcode_letter:n { 58 } % colon
\char_set_catcode_math_superscript:n { 94 } % circumflex
\char_set_catcode_letter:n { 95 } % underscore
\char_set_catcode_other:n { 124 } % pipe
\char_set_catcode_space:n { 126 } % tilde
\tex_endlinechar:D = 32 \scan_stop:
\bool_set_true:N \l_@@_expl_bool
}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</package>
% \end{macrocode}
%
% \end{implementation}
%
% \PrintIndex
|