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» Code Style
<a
target="_blank"
href="https://github.com/pmd/pmd/blob/main/docs/../pmd-xml/src/main/resources/category/xsl/codestyle.xml"
class="float-right"
role="button"
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>
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<div class="post-content" data-github-edit-url="https://github.com/pmd/pmd/blob/main/docs/../pmd-xml/src/main/resources/category/xsl/codestyle.xml">
<div class="summary">Rules which enforce a specific coding style.</div>
<details id="inline-toc-details">
<summary>Table of Contents</summary>
<div id="inline-toc"><!-- empty, move TOC here when screen size too small --></div>
</details>
<!-- DO NOT EDIT THIS FILE. This file is generated from file ../pmd-xml/src/main/resources/category/xsl/codestyle.xml. -->
<h2 id="useconcatonce">UseConcatOnce</h2>
<p><strong>Since:</strong> PMD 5.0</p>
<p><strong>Priority:</strong> Medium (3)</p>
<p>The XPath concat() functions accepts as many arguments as required so you can have
"concat($a,’b’,$c)" rather than "concat($a,concat(‘b’,$c)".</p>
<p><strong>This rule is defined by the following XPath expression:</strong></p>
<div class="language-xpath highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="o">//</span><span class="kr">node()</span><span class="p">[</span><span class="nf">contains</span><span class="p">(</span><span class="nf">substring-after</span><span class="p">(</span><span class="na">@select</span><span class="p">,</span><span class="s1">'concat'</span><span class="p">),</span><span class="s1">'concat'</span><span class="p">)]</span><span class="w">
</span></code></pre></div></div>
<p><strong>Example(s):</strong></p>
<pre><code class="language-xsl">&lt;xsl:variable name="var" select="concat("Welcome",concat("to you ",$name))"/&gt;
&lt;xsl:variable name="var" select="concat("Welcome","to you ",$name))"&gt;
</code></pre>
<p><strong>Use this rule by referencing it:</strong></p>
<div class="language-xml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt">&lt;rule</span> <span class="na">ref=</span><span class="s">"category/xsl/codestyle.xml/UseConcatOnce"</span> <span class="nt">/&gt;</span>
</code></pre></div></div>
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