XSL
PHP Manual

Predefined Constants

The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.

XSL_CLONE_AUTO (integer)
XSL_CLONE_NEVER (integer)
XSL_CLONE_ALWAYS (integer)
LIBXSLT_VERSION (integer)
libxslt version like 10117. Available as of PHP 5.1.2.
LIBXSLT_DOTTED_VERSION (string)
libxslt version like 1.1.17. Available as of PHP 5.1.2.
LIBEXSLT_VERSION (integer)
libexslt version like 813. Available as of PHP 5.1.2.
LIBEXSLT_DOTTED_VERSION (string)
libexslt version like 1.1.17. Available as of PHP 5.1.2.

XSL
PHP Manual