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<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision: 1.12 $ -->
<!-- splitted from ./en/functions/var.xml, last change in rev 1.5 -->
<refentry id="function.print-r">
<refnamediv>
<refname>print_r</refname>
<refpurpose>
Prints human-readable information about a variable
</refpurpose>
</refnamediv>
<refsect1>
<title>Description</title>
<methodsynopsis>
<type>bool</type><methodname>print_r</methodname>
<methodparam><type>mixed</type><parameter>expression</parameter></methodparam>
<methodparam choice="opt"><type>bool</type><parameter>return</parameter></methodparam>
</methodsynopsis>
<note>
<simpara>
The <parameter>return</parameter> parameter was added in PHP 4.3.0
</simpara>
</note>
<simpara>
<function>print_r</function> displays information about a variable
in a way that's readable by humans. If given a <type>string</type>,
<type>integer</type> or <type>float</type>, the value itself will be
printed. If given an <type>array</type>,
values will be presented in a format that shows keys and
elements. Similar notation is used for <type>object</type>s.
<function>print_r</function>, <function>var_dump</function> and
<function>var_export</function> will
also show protected and private properties of objects with PHP 5.
</simpara>
<simpara>
Remember that <function>print_r</function> will move the array
pointer to the end. Use <function>reset</function> to bring
it back to beginning.
</simpara>
<para>
<informalexample>
<programlisting role="php">
<![CDATA[
<pre>
<?php
$a = array ('a' => 'apple', 'b' => 'banana', 'c' => array ('x', 'y', 'z'));
print_r ($a);
?>
</pre>
]]>
</programlisting>
&example.outputs;
<screen>
<![CDATA[
<pre>
Array
(
[a] => apple
[b] => banana
[c] => Array
(
[0] => x
[1] => y
[2] => z
)
)
</pre>
]]>
</screen>
</informalexample>
</para>
<para>
If you would like to capture the output of <function>print_r</function>,
use the <parameter>return</parameter> parameter. If this parameter is set
to &true;, <function>print_r</function> will return its output, instead of
printing it (which it does by default).
</para>
¬e.uses-ob;
<para>
<example>
<title><parameter>return</parameter> parameter example</title>
<programlisting role="php">
<![CDATA[
<?php
$b = array ('m' => 'monkey', 'foo' => 'bar', 'x' => array ('x', 'y', 'z'));
$results = print_r($b, true); //$results now contains output from print_r
?>
]]>
</programlisting>
</example>
</para>
<note>
<simpara>
If you need to capture the output of <function>print_r</function> with a
version of PHP prior to 4.3.0, use the <link linkend="ref.outcontrol">
output-control functions</link>.
</simpara>
</note>
<note>
<simpara>
Prior to PHP 4.0.4, <function>print_r</function> will continue forever
if given an <type>array</type> or <type>object</type> that
contains a direct or indirect reference to itself. An example
is <literal>print_r($GLOBALS)</literal> because
<literal>$GLOBALS</literal> is itself a global variable that
contains a reference to itself.
</simpara>
</note>
<simpara>
See also <function>ob_start</function>,
<function>var_dump</function> and
<function>var_export</function>.
</simpara>
</refsect1>
</refentry>
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