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<head>
<title>UK TeX FAQ -- question label noline</title>
</head><body>
<h3>No line here to end</h3>
<p/>The error
<blockquote>
<pre>
! LaTeX Error: There's no line here to end.

See the LaTeX manual or LaTeX Companion for explanation.
</pre>

</blockquote><p>
comes in reaction to you giving LaTeX a <code>\</code><code>\</code> command at a time
when it&#8217;s not expecting it.  The commonest case is where you&#8217;ve
decided you want the label of a list item to be on a line of its own,
so you&#8217;ve written (for example):
<blockquote>
<pre>
\begin{description}
\item[Very long label] \\
  Text...
\end{description}
</pre>
</blockquote><p>
<code>\</code><code>\</code> is actually a rather bad command to use in this case (even if
it worked), since it would force the &#8216;paragraph&#8217; that&#8217;s made up of the
text of the item to terminate a line which has nothing on it but the
label.  This would lead to an &#8220;<code>Underfull \hbox</code>&#8221; warning message
(usually with &#8216;infinite&#8217; badness of 10000); while this message doesn&#8217;t
do any actual harm other than slowing down your LaTeX run, any
message that doesn&#8217;t convey any information distracts for no useful
purpose.
<p/>The proper solution to the problem is to write a new sort of
<code>description</code> environment, that does just what you&#8217;re after.  (The

<a href="FAQ-books.html"><em>LaTeX Companion</em></a> offers a
rather wide selection of variants of these things.)
<p/>The quick-and-easy solution, which avoids the warning, is to write:
<blockquote>
<pre>
\begin{description}
\item[Very long label] \hspace*{\fill} \\
  Text...
\end{description}
</pre>
</blockquote><p>
which fills out the under-full line before forcing its closure.  The
<i>expdlist</i> package provides the same functionality with its
<code>\</code><code>breaklabel</code> command, and <i>mdwlist</i> provides it via its
<code>\</code><code>desclabelstyle</code> command.
<p/>The other common occasion for the message is when you&#8217;re using the
<code>center</code> (or <code>flushleft</code> or <code>flushright</code>)
environment, and have decided you need extra separation between lines
in the environment:
<blockquote>
<pre>
\begin{center}
  First (heading) line\\
  \\
  body of the centred text...
\end{center}
</pre>
</blockquote><p>
The solution here is plain: use the <code>\\</code> command in the way it&#8217;s
supposed to be used, to provide more than just a single line break
space.  <code>\\</code> takes an optional argument, which specifies
how much extra space to add; the required effect in the text above can
be had by saying:
<blockquote>
<pre>
\begin{center}
  First (heading) line\\[\baselineskip]
  body of the centred text...
\end{center}
</pre>
</blockquote><p>
<dl>
<dt><tt><i>expdlist.sty</i></tt><dd><a href="http://www.tex.ac.uk/tex-archive/macros/latex/contrib/expdlist.zip">macros/latex/contrib/expdlist</a> (or <a href="http://www.tex.ac.uk/tex-archive/macros/latex/contrib/expdlist/">browse the directory</a>)
<dt><tt><i>mdwlist.sty</i></tt><dd>Distributed as part of <a href="http://www.tex.ac.uk/tex-archive/macros/latex/contrib/mdwtools.zip">macros/latex/contrib/mdwtools</a> (or <a href="http://www.tex.ac.uk/tex-archive/macros/latex/contrib/mdwtools/">browse the directory</a>); <a href="http://www.tex.ac.uk/tex-archive/help/Catalogue/entries/mdwlist.html">catalogue entry</a>
</dl>
<p/>
<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=noline">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=noline</a>
</body>