Re: [boost] XML APIs: use cases, and wishes

From: Graham Bennett (graham-boost_at_[hidden])
Date: 2005-11-08 20:06:05

On Tue, Nov 08, 2005 at 12:09:03AM +0100, Andreas Pokorny wrote:
> On Mon, Nov 07, 2005 at 09:46:24AM -0800, Robert Ramey <ramey_at_[hidden]> wrote:
> > > but I would like to see at least these different APIs:
> > > * on-demand parsing, a parser drived by a cursor, that allows to
> > >  navigate through a document, without loading it completly (I dont see
> > >  a need for prior validation, here)
> > 
> > The serialization library does exactly this with the spirit xml parser.
> > ...
> 
> I always assumed that spirit has full control over the parsing process,
> so the parse() function itself is the driving force to walk towards the
> end of input. The above really was about jumping through the file
> (provided that the file is well formed xml) and only examining the
> chunks around the interesting data fields. Maybe I am a bit to
> optimistic about parsing xml files :).
> 
> 
> 
> > > * direct mapper of c++ structures to a certain format, so a kind of
> > >  xml serialization,
> > 
> > I'm not sure how this differs from the xml serialization already in the
> > serialization library.
> 
> The boost::serialization archives tries to encode C++ objects in data streams,
> that might be xml documents as well. So the archive defines the format,
> and adds suficient meta information to be able to recreate the objects
> with the aid of the meta data found in the serialize-functions.
> 
> I was talking about a use case in which a certain known XML format has to be
> mapped onto C++ structures. Thus the C++ structures already got designed
> to represent the model which is discribed by that certain XML format.
> Still the binding between the format ought to be separate. 

Another case is where you have an existing XML vocabulary and you want
to create a C++ representation of it for data manipulation.  There are a
lot of tools that allow you to generate class hierarchies from XML
schema or similar, for example xsd
(http://codesynthesis.com/products/xsd/).

I don't really think Boost library should stray into this area, but it
should probably be considered as a use case for an XML API.

cheers,

Graham

-- 
Graham Bennett