1<documentation title="One Class Per File">
2    <standard>
3    <![CDATA[
4    There should only be one class defined in a file.
5    ]]>
6    </standard>
7    <code_comparison>
8        <code title="Valid: Only one class in the file.">
9        <![CDATA[
10<?php
11<em>class Foo</em>
12{
13}
14        ]]>
15        </code>
16        <code title="Invalid: Multiple classes defined in one file.">
17        <![CDATA[
18<?php
19<em>class Foo</em>
20{
21}
22
23<em>class Bar</em>
24{
25}
26        ]]>
27        </code>
28    </code_comparison>
29</documentation>
30