dom2dom: producing specialized nodes 2005-10-10 - By Joseph Kesselman
>if I pass a document Node, I get an error during the transformation
>process, it denies the creation of a new element directly under the
>document node.
Document nodes became relatively immutable in DOM Level 2 (though that's
relaxed slightly in DOM Level 3) for reasons related to subclassing of the
DOM. If you're working with a DOM that does not permit altering the
Document node's root element, you can't pass in a Document node and have
this work.
I believe there is an outstanding wishlist item to change DOMResult so we
could pass in a DOMImplementation and possibly a DocumentType (or retrieve
those from a sample Document node) , and use the
DOMImplementation.createDocument() method to properly create a new DOM
tree. But I don't think that's been implemented yet. This shouldn't be hard
to code up; if someone wants to sketch a solution and submit it, that'd be
great...
Workaround: Build into a DocumentFragment, and postprocess to
re-instantiate the root element in a new document and use importNode to
migrate the element's contents into that new element node. If the new DOM
is in the same implementation as the old one, most DOMs are able to migrate
the nodes over without having to recreate them, so this is annoying but not
expensive.
If I remember correctly, DOM Level 3 may (or may not, implementation
dependent due to the same subclassing issues) permit creating an empty
Document node and then adding to it. We'll still want the
build-via-DOMImplementation support added, though.
______________________________________
Joe Kesselman, IBM Next-Generation Web Technologies: XML, XSL and more.
"The world changed profoundly and unpredictably the day Tim Berners Lee
got bitten by a radioactive spider." -- Rafe Culpin, in r.m.filk
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