PHP 7

Information for installing this PECL extension may
be found in the manual chapter titled Installation of PECL extensions. Additional
information such as new releases, downloads, source files,
maintainer information, and a CHANGELOG, can be located here:
» https://pecl.php.net/package/regex.

PHP 5

To enable regexp support configure PHP
–with-regex[=TYPE] .
TYPE can be one of system, apache, php.
The default value is php.

The Windows version of PHP has built-in support
for this extension. You do not need to load any additional
extensions in order to use these functions.