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diff --git a/Master/texmf-dist/source/latex/base/ltnews24.tex b/Master/texmf-dist/source/latex/base/ltnews24.tex deleted file mode 100644 index 573f1e87c87..00000000000 --- a/Master/texmf-dist/source/latex/base/ltnews24.tex +++ /dev/null @@ -1,263 +0,0 @@ -% \iffalse meta-comment -% -% Copyright 2015,2016 -% The LaTeX3 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 -% http://www.latex-project.org/lppl.txt -% and version 1.3c or later is part of all distributions of LaTeX -% version 2005/12/01 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 -% Filename: ltnews24.tex -% -% This is issue 24 of LaTeX News. - -\documentclass{ltnews} -\usepackage[T1]{fontenc} - -\usepackage{lmodern,url,hologo} - -\makeatletter % -- provide command introduced in new release - % so this typesets with an old format - -% Check we are not in the preamble of a composite document -\def\@tempa{\@latex@error{Can be used only in preamble}\@eha} -\ifx\DeclareTextCommandDefault\@tempa -\else - \DeclareTextCommandDefault\textcommabelow[1] - {\hmode@bgroup\ooalign{\null#1\crcr\hidewidth\raise-.31ex - \hbox{\check@mathfonts\fontsize\ssf@size\z@ - \math@fontsfalse\selectfont,}\hidewidth}\egroup} - \DeclareTextCommandDefault\textcommaabove[1]{% - \hmode@bgroup - \ooalign{% - \hidewidth - \raise.7ex\hbox{% - \check@mathfonts\fontsize\ssf@size\z@\math@fontsfalse\selectfont`% - }% - \hidewidth\crcr - \null#1\crcr - }% - \egroup - } -\fi - -\makeatother - -\publicationmonth{February} -\publicationyear{2016} - -\publicationissue{24} - -\begin{document} - -\maketitle - -\tableofcontents - -\section{\hologo{LuaTeX} support} - -This release refines the \hologo{LuaTeX} support introduced in the -2015/10/01 release. A number of patches have been added to improve the -behavior of \package{ltluatex} (thanks largely to code review by Philipp Gesang). -The kernel code has been adjusted to -allow for changes in \hologo{LuaTeX} v0.85--v0.88. Most notably, newer -\hologo{LuaTeX} releases allow more than $16$ write streams and these are now -enabled for use by \verb|\newwrite|, but also the experimental -\texttt{newtoken} Lua library has been renamed back to \texttt{token} -which required small adjustments in the \hologo{LuaTeX} setup. - -The biggest change in \hologo{LuaTeX} v0.85--v0.87 compared to previous -versions is that all the primitives (originally defined in -\hologo{pdfTeX}) dealing with the PDF ``back end'' -are no longer defined, being replaced by a much smaller set of new primitives. -This does not directly affect the core \LaTeX{} -files in this release but has required major changes to the -\texttt{.ini} files used by \TeX{} Live and similar distributions to -set up the format files. These changes in the \hologo{LuaTeX} engine -will affect any packages using these back end commands (packages such -as \package{graphics}, \package{color}, \package{hyperref}, etc.). -Until all contributed packages are updated to the new syntax users may -need to add aliases for the old \hologo{pdfTeX} commands. A new -\package{luapdftexalias} package has been contributed to CTAN (not part of the -core \LaTeX\ release) that may be used for this purpose. - -See also the sections below for related changes in the -\textsf{tools} and \textsf{graphics} bundles. - - -\section{Unicode data} - -As noted in \LaTeX{} News~22, the 2015/01/01 release of \LaTeX{} introduced -built-in support for extended \TeX{} systems. In particular, the kernel now -loads appropriate data from the Unicode Consortium to set \verb|\lccode|, -\verb|\uccode|, \verb|\catcode| and \verb|\sfcode| values in an automated -fashion for the entire Unicode range. - -The initial approach taken by the team was to incorporate the existing model -used by (plain) \hologo{XeTeX} and to pre-process the ``raw'' Unicode data into -a ready-to-use form as \verb|unicode-letters.def|. However, the relationship -between the Unicode Consortium files and \TeX{} data structures is non-trivial and still -being explored. As such, it is preferable to directly parse the original -(\verb|.txt|) files at point of use. The team has therefore ``spun-out'' both -the data and the loading to a new generic package, \package{unicode-data}. This -package makes the original Unicode Consortium data files available in the -\verb|texmf| tree (in \verb|tex/generic/unicode-data|) and provides generic -loaders suitable for reading this data into the plain, \LaTeXe{}, and other, -formats. - -At present, the following data files are included in this new package: -\begin{itemize}\parskip=0pt - \item \verb|CaseFolding.txt| - \item \verb|EastAsianWidth.txt| - \item \verb|LineBreak.txt| - \item \verb|MathClass.txt| - \item \verb|SpecialCasing.txt| - \item \verb|UnicodeData.txt| -\end{itemize} -These files are used either by \LaTeXe{} or by \package{expl3} -(i.e.~they represent the set currently required by the team). The -Unicode Consortium provides various other data files and we would be happy to add -these to the generic package, as it is intended to provide a single place -to collect this material in the \verb|texmf| tree. Such requests can be -mailed to the team as~usual or logged at the package home page: -\url{https://github.com/latex3/unicode-data}. - -The new approach extends use of Unicode data in setting \TeX{} information in -two ways. First, the \verb|\sfcode| of all end-of-quotation/closing punctuation -is now set to $0$ (transparent to \TeX{}). Second, \verb|\Umathcode| values are -now set using \verb|MathClass.txt| rather than setting up only letters (which -was done using an arbitrary plane~$0$/plane~$1$ separation). There are also -minor refinements to the existing code setting, particularly splitting the -concepts of case and letter/non-letter category codes. - -For \hologo{XeTeX}, users should note that \verb|\xtxHanGlue| and -\verb|\xtxHanSpace| are \emph{no longer defined}, that no assignments are made -to \verb|\XeTeXinterchartoks| and that no \verb|\XeTeXintercharclass| data is -loaded into the format. The values which were previously inherited from -the plain \hologo{XeTeX} setup files are \emph{not} suitable for properly -typesetting East Asian text. There are third-party packages addressing this -area well, notably those in the \package{CTeX} bundle. Third-party packages -may need adjustment to load the data themselves; see the \textsf{unicode-data} -package for one possible loader. - -\section{More support for east European accents} - -As noted in \LaTeX{} News~23, comma accent support was added for \texttt{s} and -\texttt{t} in the 2015/10/01 release. In this release a matching -\verb|\textcommaabove| accent has been added for U+0123 (\verb|\c{g}|, -\textcommaabove{g}) which is the lower case of U+0122 (\verb|\c{G}|, -\textcommabelow{G}). In the OT1 and T1 encodings the combinations are -declared as composites with the \verb|\c| command, which matches the -Unicode names ``\textsf{latin (capital|small) letter g with cedilla}'' and -also allows \verb|\MakeUppercase{\c{g}}| to produce \verb|\c{G}|, as -required. In T1 encoding, the composite of \verb|\c| with \texttt{k}, \texttt{l}, -\texttt{n} and \texttt{r} are also -declared to use the comma below accent rather than cedilla to match the -conventional use of these letters. - -The UTF-8 \texttt{inputenc} option \texttt{utf8} has been extended to -support all latin combinations that can be reasonably constructed with a -(single) accent command an a base character for the T1 encoding so -\textcommaabove{g}, \k{u} and similar characters may be directly input -using UTF-8 encoding. - -\section{Changes in Graphics} - -The changes in \hologo{LuaTeX}~v0.87 mean that the \package{color} and -\package{graphics} packages no longer share the \texttt{pdftex.def} file -between \hologo{LuaTeX} and \hologo{pdfTeX}. A separate file -\texttt{luatex.def} (distributed separately) has been produced, and -distributions are encouraged to modify \texttt{graphics.cfg} and -\texttt{color.cfg} configuration files to default to the \texttt{luatex} -option if \hologo{LuaTeX}~v0.87 or later is being used. The team has -contributed suitable \texttt{.cfg} files to CTAN to be used -as models. - -Normally it is best to let the local \texttt{graphics.cfg} -automatically supply the right option depending on the \TeX\ engine -being used; however the \package{color} and \package{graphics} (and so -\package{graphicx}) packages have been extended to have an explicit -\texttt{luatex} option comparable to the existing \texttt{pdftex} and -\texttt{xetex} options. - -The \package{trig} package has been updated so that pre-computed values -such as $\sin(90)$ now expand to digits (\texttt{1} rather than the -internal token \verb|\@one| in this case). This allows them to be used -directly in PDF literal strings. - -\section{Changes in Tools} - -\hologo{LuaTeX} from version v0.87 no longer supports the -\verb|\write18| syntax to access system commands. A new package -\package{shellesc} has been added to \textsf{tools} that defines a new -command \verb|\ShellEscape| that may be used in all \TeX\ variants to -provide a consistent access to system commands. The package also -defines \verb|\write18| in \hologo{LuaTeX} so that it continues to access -system commands as before; see the package documentation for details. - -\section{Improving support for Unicode engines} - -\looseness=-1 -Stability concerns are always paramount when considering any change to -the \LaTeXe{} kernel. At the same time, it is important that the format -remains usable and gives reliable results for users. For the Unicode -\TeX{} engines \hologo{XeTeX} and \hologo{LuaTeX} there are important -differences in behavior from classical ($8$-bit) \TeX{} engines which -mean that identical default behaviors are not appropriate. Over the -past 18 months the team has addressed the most pressing of these -considerations (as detailed above and in \LaTeX{} News~22 and 23), -primarily by integrating existing patches into the kernel. There are, -though, important areas which still need consideration, and which -\emph{may} result in refinements to kernel support in this area in -future releases. - -The default font setup in \LaTeXe{} at present is to use the \texttt{OT1} -encoding. This assumes that hyphenation patterns have been read using -appropriate codes: the \texttt{T1} encoding is assumed. The commonly-used -hyphenation patterns today, \package{hyph-utf8}, are set up in this -way for $8$-bit engines (\hologo{pdfTeX}) but for Unicode engines use -Unicode code points. This means that hyphenation will be incorrect -with Unicode engines unless a Unicode font is loaded. This requires -a concept of a Unicode font encoding, which is currently provided by -the \package{fontspec} package in two versions, \texttt{EU1} and -\texttt{EU2}. The team is working to fully understand what is meant -by a ``Unicode font encoding'', as unlike a classical \TeX{} encoding -it is essentially impossible to know what glyphs will be provided -(though each slot is always defined with the same meaning). There -is also an overlap between this area and ideas of language and writing -system, most obviously in documents featuring mixed scripts (for example -Latin and Cyrillic). - -As well as these font considerations, the team is also exploring -to what extent it is possible to allow existing ($8$-bit) -documents to compile directly with Unicode engines without requiring -changes in the sources. Whether this is truly possible remains an open -question. - -It is important to stress that changes will only be made in this area where -they do \emph{not} affect documents processed with -\hologo{eTeX}/\hologo{pdfTeX} (i.e.~documents which are written for -``classical'' $8$-bit \TeX{} engines). Changes will also be made only where -they clearly address deficiencies in the current setup for Unicode engines -(i.e.~where current behaviors are wrong). - -\end{document} |