1<documentation title="Class Declaration">
2    <standard>
3    <![CDATA[
4    Each class must be in a file by itself and must be under a namespace (a top-level vendor name).
5    ]]>
6    </standard>
7    <code_comparison>
8        <code title="Valid: One class in a file.">
9        <![CDATA[
10<?php
11namespace Foo;
12
13<em>class Bar</em> {
14}
15        ]]>
16        </code>
17        <code title="Invalid: Multiple classes in a single file.">
18        <![CDATA[
19<?php
20namespace Foo;
21
22<em>class Bar</em> {
23}
24
25<em>class Baz</em> {
26}
27        ]]>
28        </code>
29    </code_comparison>
30    <code_comparison>
31        <code title="Valid: A vendor-level namespace is used.">
32        <![CDATA[
33<?php
34<em>namespace Foo;</em>
35
36class Bar {
37}
38        ]]>
39        </code>
40        <code title="Invalid: No namespace used in file.">
41        <![CDATA[
42<?php
43class Bar {
44}
45        ]]>
46        </code>
47    </code_comparison>
48</documentation>
49