<a href="./fr/expr.html" hreflang="fr" rel="alternate" title="Français"> fr </a></p>
</div>
- <p>Historically, there are several syntax variants for expressions used to express
- a condition in the different modules of the Apache HTTP Server.
- There is some ongoing effort to only use a single variant, called <em>ap_expr</em>,
- for all configuration directives.
- This document describes the <em>ap_expr</em> expression parser.
+ <p>Historically, there are several syntax variants for expressions
+ used to express a condition in the different modules of the Apache
+ HTTP Server. There is some ongoing effort to only use a single
+ variant, called <em>ap_expr</em>, for all configuration directives.
+ This document describes the <em>ap_expr</em> expression parser.
</p>
<p>The <em>ap_expr</em> expression is intended to replace most other
- expression variants in HTTPD. For example, the deprecated
- <code class="directive"><a href="./mod/mod_ssl.html#sslrequire">SSLRequire</a></code> expressions can be
- replaced by <a href="mod/mod_authz_core.html#reqexpr">Require expr</a>.
- </p>
+ expression variants in HTTPD. For example, the deprecated <code class="directive"><a href="./mod/mod_ssl.html#sslrequire">SSLRequire</a></code> expressions can be replaced
+ by <a href="mod/mod_authz_core.html#reqexpr">Require expr</a>. </p>
</div>
<div id="quickview"><ul id="toc"><li><img alt="" src="./images/down.gif" /> <a href="#grammar">Grammar in Backus-Naur Form notation</a></li>
<li><img alt="" src="./images/down.gif" /> <a href="#vars">Variables</a></li>
<div class="section">
<h2><a name="grammar" id="grammar">Grammar in Backus-Naur Form notation</a></h2>
- <p><a href="http://en.wikipedia.org/wiki/Backus%E2%80%93Naur_Form">Backus-Naur Form</a> (BNF) is a notation
- technique for context-free grammars, often used to describe the syntax of languages used in computing.
- In most cases, expressions are used to express boolean values.
- For these, the starting point in the BNF is <code>expr</code>. However, a few directives
- like <code class="directive"><a href="./mod/mod_log_debug.html#logmessage">LogMessage</a></code> accept expressions
- that evaluate to a string value. For those, the starting point in the BNF is <code>string</code>.
+ <p><a href="http://en.wikipedia.org/wiki/Backus%E2%80%93Naur_Form">Backus-Naur
+ Form</a> (BNF) is a notation technique for context-free grammars,
+ often used to describe the syntax of languages used in computing.
+ In most cases, expressions are used to express boolean values. For
+ these, the starting point in the BNF is <code>expr</code>.
+ However, a few directives like <code class="directive"><a href="./mod/mod_log_debug.html#logmessage">LogMessage</a></code> accept expressions
+ that evaluate to a string value. For those, the starting point in
+ the BNF is <code>string</code>.
</p>
<blockquote>
<pre>
<td>The <code class="directive"><a href="./mod/core.html#documentroot">DocumentRoot</a></code> of
the current vhost</td></tr>
<tr class="odd"><td><code>AUTH_TYPE</code></td>
- <td>The configured <code class="directive"><a href="./mod/mod_authn_core.html#authtype">AuthType</a></code>
- (e.g. "<code>basic</code>")</td></tr>
+ <td>The configured <code class="directive"><a href="./mod/mod_authn_core.html#authtype">AuthType</a></code> (e.g.
+ "<code>basic</code>")</td></tr>
<tr><td><code>CONTENT_TYPE</code></td>
<td>The content type of the response</td></tr>
<tr class="odd"><td><code>HANDLER</code></td>
<td>The day of the week (starting with <code>0</code>
for Sunday)</td></tr>
<tr class="odd"><td><code>TIME</code></td>
- <td>The date and time in the format <code>20101231235959</code></td></tr>
+ <td>The date and time in the format
+ <code>20101231235959</code></td></tr>
<tr><td><code>SERVER_SOFTWARE</code></td>
<td>The server version string</td></tr>
<tr class="odd"><td><code>API_VERSION</code></td>
<td>The date of the API version (module magic number)</td></tr>
</table>
- <p>Some modules register additional variables, see e.g. <code class="module"><a href="./mod/mod_ssl.html">mod_ssl</a></code>.</p>
+ <p>Some modules register additional variables, see e.g.
+ <code class="module"><a href="./mod/mod_ssl.html">mod_ssl</a></code>.</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
<div class="section">
"<code>false</code>", or "<code>no</code>" (case insensitive).
True otherwise.</td><td /></tr>
<tr><td><code>-R</code></td>
- <td>Same as "<code>%{REMOTE_ADDR} -ipmatch ...</code>", but more efficient
+ <td>Same as "<code>%{REMOTE_ADDR} -ipmatch ...</code>", but more
+ efficient
</td><td /></tr>
</table>
<tr><td><code>resp</code></td>
<td>Get HTTP response header</td><td /></tr>
<tr class="odd"><td><code>reqenv</code></td>
- <td>Lookup request environment variable (as a shortcut, <code>v</code> can be used too to access variables).</td><td /></tr>
+ <td>Lookup request environment variable (as a shortcut,
+ <code>v</code> can be used too to access
+ variables).</td><td /></tr>
<tr><td><code>osenv</code></td>
<td>Lookup operating system environment variable</td><td /></tr>
<tr class="odd"><td><code>note</code></td>
the expression. The <code>req_novary</code> function can be used to
prevent names from being added to the Vary header.</p>
- <p>In addition to string-valued functions, there are also list-valued functions which
- take one string as argument and return a wordlist, i.e. a list of strings. The wordlist
- can be used with the special <code>-in</code> operator.
- Functions names are not case sensitive.
- Modules may register additional functions.</p>
+ <p>In addition to string-valued functions, there are also
+ list-valued functions which take one string as argument and return a
+ wordlist, i.e. a list of strings. The wordlist can be used with the
+ special <code>-in</code> operator. Functions names are not case
+ sensitive. Modules may register additional functions.</p>
<p>There are no built-in list-valued functions. <code class="module"><a href="./mod/mod_ssl.html">mod_ssl</a></code>
provides <code>PeerExtList</code>. See the description of
<h2><a name="examples" id="examples">Example expressions</a></h2>
- <p>The following examples show how expressions might be used to evaluate requests:</p>
+ <p>The following examples show how expressions might be used to
+ evaluate requests:</p>
+
<pre class="prettyprint lang-config">
# Compare the host name to example.com and redirect to www.example.com if it matches
<td>string contained in string list</td></tr>
<tr class="odd"><td><code>/regexp/</code></td>
<td><code>m#regexp#</code></td>
- <td>Regular expression (the second form allows different delimiters than /)</td></tr>
+ <td>Regular expression (the second form allows different
+ delimiters than /)</td></tr>
<tr><td><code>/regexp/i</code></td>
<td><code>m#regexp#i</code></td>
<td>Case insensitive regular expression</td></tr>
projects / thirdparty / apache / httpd.git / commitdiff
