An xml comment in xml::dom
XML::DOM::Comment extends XML::DOM::CharacterData which extends XML::DOM::Node.
This node represents the content of a comment, i.e., all the characters between the starting '<!--' and ending '-->'. Note that this is the definition of a comment in \s-1XML\s0, and, in practice, \s-1HTML\s0, although some \s-1HTML\s0 tools may implement the full \s-1SGML\s0 comment structure.