(PHP 5, PHP 7)
The DOMImplementation interface provides a number of methods for performing operations that are independent of any particular instance of the document object model.
$namespaceURI = NULL
[, string $qualifiedName = NULL
[, DOMDocumentType $doctype = NULL
]]] ) : DOMDocument$qualifiedName = NULL
[, string $publicId = NULL
[, string $systemId = NULL
]]] ) : DOMDocumentType