cvs: phpdoc /en/functions regex.xml

jimw Thu Nov 1 21:18:24 2001 EDT Modified files: /phpdoc/en/functions regex.xml Log: steer people towards pcre functions. incorporate notes and examples from user notes. Index: phpdoc/en/functions/regex.xml diff -u phpdoc/en/functions/regex.xml:1.27 phpdoc/en/functions/regex.xml:1.28 --- phpdoc/en/functions/regex.xml:1.27 Fri Sep 21 18:47:46 2001 +++ phpdoc/en/functions/regex.xml Thu Nov 1 21:18:24 2001 @@ -1,10 +1,25 @@ <?xml encoding="iso-8859-1"?> -<!-- $Revision: 1.27 $ --> +<!-- $Revision: 1.28 $ --> <reference id="ref.regex"> <title>Regular Expression Functions (POSIX Extended)</title> <titleabbrev>Regexps</titleabbrev> <partintro> + <note> + <para> + PHP also supports regular expressions using a Perl-compatible syntax + using the <link linkend="ref.pcre">PCRE functions</link>. Those functions + support non-greedy matching, assertions, conditional subpatterns, and a + number of other features not supported by the POSIX-extended regular + expression syntax. + </para> + </note> + <warning> + <para> + These regular expression functions are not binary-safe. The <link + linkend="ref.pcre">PCRE functions</link> are. + </para> + </warning> <para> Regular expressions are used for complex string manipulation in PHP. The functions that support regular expressions are: @@ -35,9 +50,6 @@ directory in the PHP distribution. It's in manpage format, so you'll want to do something along the lines of <command>man /usr/local/src/regex/regex.7</command> in order to read it. - - <!-- Should add discussion of PCRE functions here. --> - </para> <para> <example> @@ -63,11 +75,11 @@ /* Places three space separated words into $regs[1], $regs[2] and $regs[3]. */ -$string = ereg_replace ("^", "&lt;BR&gt;", $string); -/* Put a &lt;BR&gt; tag at the beginning of $string. */ +$string = ereg_replace ("^", "&lt;br /&gt;", $string); +/* Put a &lt;br /&gt; tag at the beginning of $string. */ -$string = ereg_replace ("$", "&lt;BR&gt;", $string); -/* Put a &lt;BR&gt; tag at the end of $string. */ +$string = ereg_replace ("$", "&lt;br /&gt;", $string); +/* Put a &lt;br /&gt; tag at the end of $string. */ $string = ereg_replace ("\n", "", $string); /* Get rid of any newline @@ -94,6 +106,13 @@ </paramdef> </funcprototype> </funcsynopsis> + <note> + <para> + <function>preg_match</function>, which uses a Perl-compatible + regular expression syntax, is often a faster alternative to + <function>ereg</function>. + </para> + </note> <simpara> Searches a <parameter>string</parameter> for matches to the regular expression given in <parameter>pattern</parameter>. @@ -140,8 +159,9 @@ </para> <simpara> See also <function>eregi</function>, - <function>ereg_replace</function>, and - <function>eregi_replace</function>. + <function>ereg_replace</function>, + <function>eregi_replace</function> and + <function>preg_match</function>. </simpara> </refsect1> </refentry> @@ -161,6 +181,13 @@ <paramdef>string <parameter>string</parameter></paramdef> </funcprototype> </funcsynopsis> + <note> + <para> + <function>preg_replace</function>, which uses a Perl-compatible + regular expression syntax, is often a faster alternative to + <function>ereg_replace</function>. + </para> + </note> <simpara> This function scans <parameter>string</parameter> for matches to <parameter>pattern</parameter>, then replaces the matched text @@ -224,9 +251,18 @@ </programlisting> </example> </para> + <para> + <example> + <title>Replace URLs with links</title> + <programlisting role="php"> +$text = ereg_replace("[[:alpha:]]+://[^<>[:space:]]+[[:alnum:]/]", + "&lt;a href=\"\\0\"&gt;\\0&lt;/a&gt;", $text); + </programlisting> + </example> + </para> <simpara> See also <function>ereg</function>, <function>eregi</function>, - and <function>eregi_replace</function>. + <function>eregi_replace</function>, and <function>preg_match</function>. </simpara> </refsect1> </refentry> @@ -252,6 +288,14 @@ This function is identical to <function>ereg</function> except that this ignores case distinction when matching alphabetic characters. + <example> + <title><function>eregi</function> example</title> + <programlisting role="php"> +if (eregi("z", $string)) { + echo "'$string' contains a 'z' or 'Z'!"; +} + </programlisting> + </example> </para> <para> See also <function>ereg</function>, @@ -305,6 +349,13 @@ </paramdef> </funcprototype> </funcsynopsis> + <note> + <para> + <function>preg_split</function>, which uses a Perl-compatible + regular expression syntax, is often a faster alternative to + <function>split</function>. + </para> + </note> <para> Returns an array of strings, each of which is a substring of <parameter>string</parameter> formed by splitting it on @@ -321,7 +372,7 @@ <example> <title><function>split</function> Example</title> <programlisting role="php"> -$passwd_list = split (":", $passwd_line, 5); +list($user,$pass,$uid,$gid,$extra)= split (":", $passwd_line, 5); </programlisting> </example> </para> @@ -359,7 +410,7 @@ </para> <para> - For users looking for a way to emulate perl's <command>$chars = + For users looking for a way to emulate Perl's <command>$chars = split('', $str)</command> behaviour, please see the examples for <function>preg_split</function>. </para>