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author | Karl Berry <karl@freefriends.org> | 2020-01-13 21:30:36 +0000 |
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committer | Karl Berry <karl@freefriends.org> | 2020-01-13 21:30:36 +0000 |
commit | ce9eb3564e7376e4452732aef5229a8461f52a09 (patch) | |
tree | 421c616b3d0f26ddc6e20e28345c9bd680028708 /Master/texmf-dist/doc/latex/l3kernel/l3news04.tex | |
parent | a61c6cf82707ad0e3aab14106179ce8d199284ce (diff) |
l3 (13jan20)
git-svn-id: svn://tug.org/texlive/trunk@53394 c570f23f-e606-0410-a88d-b1316a301751
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diff --git a/Master/texmf-dist/doc/latex/l3kernel/l3news04.tex b/Master/texmf-dist/doc/latex/l3kernel/l3news04.tex new file mode 100644 index 00000000000..a0fc82f3ded --- /dev/null +++ b/Master/texmf-dist/doc/latex/l3kernel/l3news04.tex @@ -0,0 +1,123 @@ +% Copyright 2009,2010 The LaTeX Project +\documentclass{ltnews} +\PassOptionsToPackage{colorlinks}{hyperref} + +\usepackage{metalogo,ragged2e} + +\AtBeginDocument{ + \renewcommand{\LaTeXNews}{\LaTeX3~News} + \RaggedRight +} + +\usepackage{url,hologo} + +\publicationmonth{July} +\publicationyear{2010} +\publicationissue{4} + +\begin{document} +\maketitle + +\noindent +Now that we're back from the \TeX\ Users Group conference in San +Francisco, it's time to discuss what's been going on over the last six months. +Due to some extra travel plans after the conference, this issue is slightly +late in coming out. + + +\section{\textsf{expl3} in practice} + +Joseph Wright and Will Robertson have both released significant new versions +of their packages, resp., \textsf{siunitx} and \textsf{fontspec}. These have +been re-written in the \LaTeX3 programming language \textsf{expl3}, which we +have discussed here previously. Using \textsf{expl3} for production code has +been very successful, both in demonstrating that the concepts are sound and +highlighting areas that still need some attention. +% The \textsf{expl3} +% code will continue to evolve as more people use it for their work. + +In the case of \textsf{fontspec}, \textsf{expl3} programming is being used to +target \LaTeX\ running on either \XeTeX\ and \hologo{LuaTeX}. In the latter +case, the package is a mixture of Lua code and \pkg{expl3} code; Will +presented the \pkg{unicode-math} package at TUG~2010, which is developed in +the same style. + + +\section{New \textsf{xpackages}} + +Frank Mittelbach has started to work on a new experimental \LaTeX3 package +\textsf{xhead} that provides templates for one of the most complex areas of +document design: section headings and document divisions. This +is the beginning of an ambitious idea to map out the requirements for +typesetting most documents currently processed with \LaTeX. + +One of the challenges here is providing a ``natural'' design language for +describing the two-dimensional spatial relationships of objects participating +in the design, e.g., the placement of a heading number in relation to the +heading title, a possible sub-title, etc. In answer to this challenge Frank +developed the \textsf{xcoffin} package, which he presented at TUG~2010. It is +designed as a high-level interface for placing and aligning boxes on a page, +allowing a `designer's approach' for indicating the positional relationship +between boxes. (A `coffin' is a box with handles.) As an example, it is +possible to represent ideas such as `align the lower-left corner of box A with +the upper-right corner of box B after rotating it ninety degrees', without +having to calculate the intermediate positions. + +We expect a future version of \textsf{xcoffin} (after some further work on its +interface layer and its internal implementation) to play a major role in all +packages providing layout templates for higher-level document objects, such as +table of contents designs, floats, etc. + +Finally, +Joseph Wright has begun work with the current `galley' packages, producing the +new, minimal, \textsf{xgalley} based on \textsf{xfm-galley} as a testbed for +what we need and what will work. + + +\section{Developments with \textsf{expl3}} + +Meanwhile, Joseph's \emph{also} been writing a new floating-point calculation +module, called \textsf{l3fp}, for \pkg{expl3}. This module allows manipulation +and calculation of numbers with a much larger range than \TeX\ allows +naturally. The \textsf{l3fp} module has already been utilised in the +\pkg{xcoffin} code for calculatations such as coordinate rotations and +intersection points of vectors. + +The modules \pkg{l3io} and \pkg{l3file} have been revised, rethinking the way +that read and write streams are dealt with. \TeX\ has a hard limit of sixteen +input and output streams open at any one time, and the new implementation for +\pkg{expl3} provides more flexibility in how they are allocated; there's now +much less chance of running into a `\verb|No room for a new \read|' (or +\verb|\write|) error. + +Sometimes we discuss ideas for \textsf{expl3} that \emph{don't} end up making +it into the final code. One example of this is the concept of having `local +registers' for integers, boxes, and so on, that do not survive outside of the +group they are defined in (in contrast to Plain \TeX\ and \LaTeX, where +allocators such as \verb|\newcount| and \verb|\newbox| are always global). +Despite the scope for some small benefit, we decided that the extra complexity +that the additional functions required, in both syntax and documentation, was +not justified. + + +\section{TUG 2010 reflections} + +% added most of it back in: -fmi + +%% Most of the active \LaTeX3 Project team were able to attend the TUG~2010 +%% conference and (for Will) meet everyone in person for the first time. + +Our interpretation of the broad themes discussed at the conference are that +\TeX-based systems are still thriving and there are some big problems to solve +with robust solutions to transform \LaTeX\ source, including mathematics, into +a form such as HTML. While there are big pushes for standardising various aspects +of the \LaTeX\ syntax, we also believe that it is \LaTeX's very +flexibility---its inherently non-standardised markup---that has allowed it to +survive for so many years. There is a delicate trade-off here between moving +forward into more standards-based territory while also retaining the +extensibility of the third-party package system. + +\end{document} + + + |