Mellel's XML DTD, Schema or stylesheet?

[mkenney]

I've been examining the xml component of some of my Mellel packages. Am I correct in thinking that not only are there elements denoting logical structure in the document, but also code specifying formatting?

Also, is Mellel making use of an established DTD, schema or stylesheet (e.g., TEI or TEI-lite)? I recall references to a XMelleL somewhere on the forum or in the user's guide. So, are the entities proprietary? If a Mellel document cannot be validated against, say, TEI-Lite, or some other open DTD, Schema, or stylesheet, isn't someone going to need to do a great deal of work (crafting transformation specifications) to make Mellel docs truly portable?

I ask these questions out of curiosity, and as an XML novice (I understand the purpose of XML and the notion of entities, style sheets, etc., but have not yet gotten a hold on the details of XML parsing, validating, transformation and the like).

[rpcameron]

The XML schema that powers Mellel has not yet been released. However, Eyal has indicated that the full documentation will be forthcoming.

[Stephen Still]

I've been examining the xml component of some of my Mellel packages. Am I correct in thinking that not only are there elements denoting logical structure in the document, but also code specifying formatting?

Yes, but it's very well separated from the content.

Each <p> or <c> element has a style attribute and (potentially) an override attribute, which refer to predefined formatting values, set up at the top of the document tree. Otherwise, there is very little formatting information in the actual text of the document.

Also, is Mellel making use of an established DTD, schema or stylesheet (e.g., TEI or TEI-lite)? I recall references to a XMelleL somewhere on the forum or in the user's guide. So, are the entities proprietary? If a Mellel document cannot be validated against, say, TEI-Lite, or some other open DTD, Schema, or stylesheet, isn't someone going to need to do a great deal of work (crafting transformation specifications) to make Mellel docs truly portable?

It's a proprietary XML format, and the DTD/Schema/whatever hasn't yet been released. This is obviously a problem for Mellel producing applications, but isn't really all that much of a problem for consuming applications, since it's fair to assume that Mellel will always turn out correct Mellel XML files.

I ask these questions out of curiosity, and as an XML novice (I understand the purpose of XML and the notion of entities, style sheets, etc., but have not yet gotten a hold on the details of XML parsing, validating, transformation and the like).

There are two main aspects of XML validation: well-formedness (i.e. does the document adhere to the rules set out in the XML specification), and validity (i.e. does it conform to the DTD for the specific document type). A nice command line tool for checking these on OS X is xmlwf. Check it out.

In terms of styling, Mellel uses its own internal XML-based style system, which is generally quite elegant, although it completely lacks inheritance (as you would expect, from the lack of this functionality in the application itself).