Re: [xml] using xmlDocSetRootElement to move nodes between documents

[Daniel Veillard <veillard redhat com>]

On Wed, Jul 28, 2004 at 11:50:00AM +0200, Martijn Faassen wrote:
> >  You are right. There have been attempts to solve this with 
> >  xmlReconciliateNs
> > in tree.c this should solve namespace problems. Other potential problem is
> > entities references.
>
> So basically the conclusion is that there is no safe way to move nodes 
> between documents in libxml2 at this point in time? I don't mind having 
> to call some function to 'import' nodes into a different tree, but it 
> seems I have to worry about namespaces, dictionaries and entities at 
> least. Right now I'm using xmlDocCopyNode(), which appears to work, 
> isn't the right semantics for the API I'm trying to implement, which 
> allows free movements of elements between trees.
>
> What would a function look like that that can be used to safely import a 
> node (and its subnodes) from one document to another? Could this 
> function do its work relatively efficiently?

  The efficiency is the problem. Recursing down the subtree generate cost.
It's possible to share dictionaries for multiple documents, it's possible
to reconciliate namespaces, but entities if not substitued on parse are
a serious problem, you may have to add them on the internal subset of the
target.

Daniel

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