php-doc-en/reference/apc/functions/apc-define-constants.xml
Sean Coates f73e515b9c tyop
git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@231056 c90b9560-bf6c-de11-be94-00142212c4b1
2007-03-03 02:17:58 +00:00

151 lines
4.1 KiB
XML

<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision: 1.4 $ -->
<refentry id="function.apc-define-constants">
<refnamediv>
<refname>apc_define_constants</refname>
<refpurpose>
Defines a set of constants for retrieval and mass-definition
</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>bool</type><methodname>apc_define_constants</methodname>
<methodparam><type>string</type><parameter>key</parameter></methodparam>
<methodparam><type>array</type><parameter>constants</parameter></methodparam>
<methodparam choice="opt"><type>bool</type><parameter>case_sensitive</parameter></methodparam>
</methodsynopsis>
<para>
<function>define</function> is notoriously slow. Since the main benefit of
APC is to increase the performance of scripts/applications, this mechanism
is provided to streamline the process of mass constant definition. However,
this function does not perform as well as anticipated.
</para>
<para>
For a better-performing solution, try the
<ulink url="&url.pecl.package;hidef">hidef</ulink> extension from PECL.
</para>
<note>
<simpara>
To remove a set of stored constants (without clearing the entire cache), an
empty array may be passed as the <parameter>constants</parameter>
parameter, effectively clearing the stored value(s).
</simpara>
</note>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<para>
<variablelist>
<varlistentry>
<term><parameter>key</parameter></term>
<listitem>
<para>
The <parameter>key</parameter> serves as the name of the constant set
being stored. This <parameter>key</parameter> is used to retrieve the
stored constants in <function>apc_load_constants</function>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>constants</parameter></term>
<listitem>
<para>
An associative array of <literal>constant_name => value</literal>
pairs. The <literal>constant_name</literal> must follow the normal
<link linkend="language.constants">constant</link> naming rules.
<literal>value</literal> must evaluate to a scalar value.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>case_sensitive</parameter></term>
<listitem>
<para>
The default behaviour for constants is to be declared case-sensitive;
i.e. <literal>CONSTANT</literal> and <literal>Constant</literal>
represent different values. If this parameter evaluates to &false; the
constants will be declared as case-insensitive symbols.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
&return.success;
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<example>
<title><function>apc_define_constants</function> example</title>
<programlisting role="php">
<![CDATA[
<?php
$constants = array(
'ONE' => 1,
'TWO' => 2,
'THREE' => 3,
);
apc_define_constants('numbers', $constants);
echo ONE, TWO, THREE;
?>
]]>
</programlisting>
&example.outputs;
<screen>
<![CDATA[
123
]]>
</screen>
</example>
</para>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member><function>apc_load_constants</function></member>
<member><function>define</function></member>
<member><function>constant</function></member>
<member>
Or <link linkend="language.constants">the PHP constants reference</link>
</member>
</simplelist>
</para>
</refsect1>
</refentry>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"../../../../manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->