libxml-regexp-perl 0.04-1 (amd64 binary) in ubuntu cosmic

 The XML::RegExp module provides regular expressions for the following XML
 tokens: BaseChar, Ideographic, Letter, Digit, Extender,
 CombiningChar, NameChar, EntityRef, CharRef, Reference, Name,
 NmToken, and AttValue.
 .
 The definitions of these tokens were taken from the XML spec
 (Extensible Markup Language 1.0) at http://www.w3.org/TR/REC-xml.
 .
 Also contains the regular expressions for the following tokens from
 the XML Namespaces spec at http://www.w3.org/TR/REC-xml-names:
 NCNameChar, NCName, QName, Prefix and LocalPart.