php-doc-en/language/control-structures/continue.xml
Christoph Michael Becker 7104ee97ce Removed literal tags from title for readability
Closes GH-250.


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@351935 c90b9560-bf6c-de11-be94-00142212c4b1
2020-12-06 22:38:36 +00:00

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<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<sect1 xml:id="control-structures.continue" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
<title>continue</title>
<?phpdoc print-version-for="continue"?>
<simpara>
<literal>continue</literal> is used within looping structures to
skip the rest of the current loop iteration and continue execution
at the condition evaluation and then the beginning of the next iteration.
</simpara>
<note>
<simpara>
In PHP the
<link linkend="control-structures.switch">switch</link> statement is
considered a looping structure for the purposes of
<literal>continue</literal>. <literal>continue</literal> behaves like
<literal>break</literal> (when no arguments are passed) but will
raise a warning as this is likely to be a mistake. If a
<literal>switch</literal> is inside a loop,
<literal>continue 2</literal> will continue with the next iteration
of the outer loop.
</simpara>
</note>
<simpara>
<literal>continue</literal> accepts an optional numeric argument
which tells it how many levels of enclosing loops it should skip
to the end of. The default value is <literal>1</literal>, thus skipping
to the end of the current loop.
</simpara>
<para>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
foreach ($arr as $key => $value) {
if (!($key % 2)) { // skip even members
continue;
}
do_something_odd($value);
}
$i = 0;
while ($i++ < 5) {
echo "Outer<br />\n";
while (1) {
echo "Middle<br />\n";
while (1) {
echo "Inner<br />\n";
continue 3;
}
echo "This never gets output.<br />\n";
}
echo "Neither does this.<br />\n";
}
?>
]]>
</programlisting>
</informalexample>
</para>
<para>
Omitting the semicolon after <literal>continue</literal> can lead to
confusion. Here's an example of what you shouldn't do.
</para>
<para>
<informalexample>
<programlisting role="php">
<![CDATA[
<?php
for ($i = 0; $i < 5; ++$i) {
if ($i == 2)
continue
print "$i\n";
}
?>
]]>
</programlisting>
<para>
One can expect the result to be:
</para>
<screen>
<![CDATA[
0
1
3
4
]]>
</screen>
</informalexample>
</para>
<para>
<table>
<title>Changelog for <literal>continue</literal></title>
<tgroup cols="2">
<thead>
<row>
<entry>&Version;</entry>
<entry>&Description;</entry>
</row>
</thead>
<tbody>
<row>
<entry>7.3.0</entry>
<entry>
<literal>continue</literal> within a <literal>switch</literal> that is attempting to act like a <literal>break</literal> statement for the
<literal>switch</literal> will trigger an <constant>E_WARNING</constant>.
</entry>
</row>
</tbody>
</tgroup>
</table>
</para>
</sect1>
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