Dom Level 1 starts, there is already DomImPlementation.hasfeature (Feature, Version) to test the Features supported by DOM.
However, it may be because Dom Level 2 has official MODULIZATION, so it is clearly ambiguous place in DOM1.
Dom Level 2 has 14 modules, such as Core, XML, HTML, etc. Two Module: Core, XML actually defined in DOM Core REC, respectively correspond to FoundAmental Interfaces and Extended Interfaces (CDATA, Entity, Pi, DOCTYPE, etc.). The two are distinguishing between HTML. For HTML-ONLY IMPL, it is not necessary to implement the latter.
Exterior: In fact, some methods in Core (such as createDocument, createDocumenttype, etc. in DOM2) are HTML- Only's IMPL does not need to be implemented, or designed as, if it is HTML DOC, throw NOT_SUPPORTED_ERR's DOMEXCEPTION (such as DOM1 CreateCDataction, etc.). The split point of the module has entered the interior of the class or interface. So or use text description or throw the unsupported Exception. A comparative college style, either recreate a set of interfaces, and then XML and HTML have inherited the extension. But this may be too cumbersome (DOM is not cumbersome?) ... and there is no HTML only XHTML in the future, XHTML is also XML, there is no html-only, so there is no exception that can not be implemented.
Back to the topic. For DOM Level 1, the Feature parameter of the Hasfeature method can only be "XML" and "HTML", but the semantics have not been described in REC - ie not explained what is XML Feature what is HTML Feature. This is a mixture. There is no clarification in Errata.
2000/9 The 2nd Edition released in 2000 increased the CoML and HTML meaning as DOM2. But inside DOM1 is not Core this feature is available for testing, because all Compliant's IMPL has been specified. That is also, this is the most basic part. If you don't support it, can you call the DOM implementation? The rest of the problem is that the 2nd Ed Ed of this followed by the process should be a Working Draft. Therefore, this clarification is still not included in the formal standard. Maybe you should ask the Dom Mailing List (or have someone else to ask?) ......
