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diff --git a/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-atsigns.html b/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-atsigns.html new file mode 100644 index 00000000000..1c73cdc7fbe --- /dev/null +++ b/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-atsigns.html @@ -0,0 +1,52 @@ +<head> +<title>UK TeX FAQ -- question label atsigns</title> +</head><body> +<h3><code>\</code><code>@</code> and <code>@</code> in macro names</h3> +<p/>Macro names containing <code>@</code> are <em>internal</em> to LaTeX, and +without special treatment just don’t work in ordinary use. A nice +example of the problems caused is discussed in +<a href="FAQ-atvert.html"><code>\</code><code>@</code> in vertical mode</a>”. +<p/>The problems users see are caused by copying bits of a class +(<code>.cls</code> file) or +package (<code>.sty</code> file) into a document, or by including a class or +package file into a LaTeX document by some means other than +<code>\</code><code>documentclass</code> or <code>\</code><code>usepackage</code>. LaTeX defines internal +commands whose names contain the character <code>@</code> to +avoid clashes between its internal names and names that we would +normally use in our documents. In order that these commands may work +at all, <code>\</code><code>documentclass</code> and <code>\</code><code>usepackage</code> play around with the +meaning of <code>@</code>. +<p/>If you’ve included a file some other way (for example, using +<code>\</code><code>input</code>), you can probably solve the problem by using the correct +command. +<p/>If you’re using a fragment of a package or class, you may well feel +confused: books such as the first edition of the +<a href="FAQ-books.html">The LaTeX Companion</a> +are full of fragments of packages as examples for you to employ. +The second edition of the <em>Companion</em> makes clearer how you +should use these fragments, and in addition, the code of +all the examples is now available on CTAN. +To see the technique in practice, look at the example below, from file +<i>2-2-7.ltx</i> in the <em>Companion</em> examples directory: +<blockquote> +<pre> +\makeatletter +\renewcommand\subsection{\@startsection + {subsection}{2}{0mm}%name, level, indent + {-\baselineskip}% beforeskip + {0.5\baselineskip}% afterskip + {\normalfont\normalsize\itshape}}% style +\makeatother +</pre> +</blockquote><p> +(That example appears on page 29 of <em>The LaTeX Companion</em>, +second edition.) +<p/>The alternative is to treat all these fragments as a package proper, +bundling them up into a <code>.sty</code> file and including them with +<code>\</code><code>usepackage</code>; this way you hide your LaTeX internal code somewhere +that LaTeX internal code is expected, which often looks ‘tidier’. +<dl> +<dt><tt><i>Examples from the Companion</i></tt><dd><a href="ftp://cam.ctan.org/tex-archive/info/examples/tlc2.zip">info/examples/tlc2</a> (<a href="ftp://cam.ctan.org/tex-archive/info/examples/tlc2.tar.gz">gzipped tar</a>, <a href="http://www.tex.ac.uk/tex-archive/info/examples/tlc2/">browse</a>) +</dl> +<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=atsigns">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=atsigns</a> +</body> |