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+% \iffalse meta-comment
+%
+% Copyright (C) 2017-2019
+% 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 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
+% Filename: ltnews27.tex
+%
+% This is issue 27 of LaTeX News.
+
+\documentclass{ltnews}
+\usepackage[T1]{fontenc}
+
+\usepackage{lmodern,url,hologo}
+
+\publicationmonth{April}
+\publicationyear{2017}
+
+\publicationissue{27}
+
+\begin{document}
+
+\maketitle
+\tableofcontents
+
+\setlength\rightskip{0pt plus 3em}
+
+\section{ISO 8601 Date format}
+Since before the first releases of \LaTeXe, \LaTeX\ has used a date
+format in the form \textsc{yyyy/mm/dd}. This has many advantages over more
+conventional formats, as it is easy to sort and avoids the unfortunate
+ambiguity between different communities as to whether 01/02/2017 is the
+1st of February or 2nd of January.
+
+However there is another date format, formalised by the
+International Standard ISO~8601. The basic format defined by this
+standard is functionally equivalent to the \LaTeX\ format, but using
+\texttt{-} rather than \texttt{/}. This date format is now supported
+in many Operating Systems and applications
+(for example the \verb|date --iso-8601| command in Linux and similar systems).
+
+From this release, \LaTeX\ will accept ISO format date strings in the
+date argument of \verb|\ProvidesPackage|, \verb|\usepackage|, etc.
+Currently we recommend that you do not use this format in any packages
+that need to work with older \LaTeX\ releases;
+the \textsf{latexrelease} package may be used with older releases to
+ add this functionality. This change is handled in a special way by
+ \textsf{latexrelease}: The package always adds support for ISO dates
+whatever format date is requested; this is required so that the
+necessary date comparisons may be made.
+
+The new functionality can be seen in the startup banner which
+advertises \texttt{LaTeX2e <2017-04-15>}.
+
+\section{Further TU encoding improvements}
+The 2017/01/01 release saw the introduction of the new TU encoding for
+specifying Unicode fonts with \hologo{LuaTeX} and
+\hologo{XeTeX}. There were a number of small corrections and additions
+in the patch releases updating 2017/01/01, and a further addition in
+this release, notably extended support for the dot-under accent,
+\verb|\d|.
+
+
+\section{Disabling hyphenation}
+The existing \LaTeX\ code for \verb|\verb| and \verb|verbatim| had some
+issues when used with fonts that were not loaded with hyphenation
+disabled via setting \verb|\hyphenchar| to $-1$. In this release these
+verbatim environments use a \verb|\language| setting,
+\verb|\l@nohyphenation|, that has no hyphenation patterns associated.
+
+The format ensures that a language has been allocated with this name.
+For most users this will in fact be no change as the standard
+\textsf{babel} language has for a long time allocated a language with
+this name.
+
+In order that page breaks in \texttt{verbatim} do not influence the
+language used in the page head and foot, the format now normalises the
+language used in the output routine to a default language as described
+below.
+
+\section{Discretionary hyphenation}
+The \LaTeX\ definition of \verb|\-| has been adjusted so that it will
+insert the current font's \verb|\hyphenchar|, as would the
+\TeX\ primitive. A comment in \textsf{source2e} has given
+this new definition since the first releases of \LaTeXe, and in this
+release we finally acted upon this comment. Previously \verb|\-|
+always inserted a \texttt{-} at a break point even if a different
+character would be used for automatic hyphenation with the current font.
+
+\section{Default document language}
+
+A new integer parameter \verb|\document@default@language| is
+introduced; this is initialised to $-1$ but is set at
+\verb|\begin{document}| to the language in force at that time if it
+ has not been set by preamble code. This is very similar to the
+ handling of the default color, and is used in a similar way to
+ normalise the settings for page head and foot as described above.
+Users should not normally need to set this explicitly but it is expected that
+language packages such as \textsf{babel} may set this if the default
+behaviour is not suitable.
+
+\section{Line spacing in parboxes}
+Inside a \verb|\parbox|
+\LaTeX\ normalises the baseline spacing. However it has not
+previously reset \verb|\lineskiplimit|. This meant that
+lines of a paragraph that have ascenders or descenders could be set
+with \emph{closer} line spacing than lines without. This can easily
+happen if you use a \verb|\parbox| in an AMS alignment, as they use a
+relatively large value of \verb|\lineskiplimit|.
+As usual, the \textsf{latexrelease} package may be used to
+force the older behavior.
+
+\end{document}