Re: [boost] RFC: Boost.XML API prototype in the sandbox ->generation form xsd

From: Stefan Seefeld (seefeld_at_[hidden])
Date: 2007-07-13 11:15:00

Jake Voytko wrote:
> My concern, as I indicated in the other thread, is that

[...]

> are all valid XML documents, and represent the same data. If this library
> were solely to be used for writing, I would say that this is not an issue.
> However, what is written must be read.

I'm not sure what you are driving at. The parsing of XML files is well specified,
and that's what libxml2 implements.

> The thing I don't understand about the type-safety proposals is how they
> intend to take into account data that is read from a file. Suppose we write
> a program to neatly display XML data from any generic XML file:
> 
>    boost::xml my_doc_reader(filename);
> 
> would certainly be a step, and I would expect it to contain a full XML tree
> after this step is said and done with no extra intervention. The XML library
> certainly can't instantiate the proper structs in memory if we don't know
> what they are. Do they exist solely for writing the document?
> 
> To me, type safety is a more specific problem than what the XML standard
> deals with.

Indeed, and so, for the purpose of keeping this XML proposal on track, I'd
suggest to disregard any type safety issues that don't directly derive from
XML well-formedness. XML validation (no matter what schema is used to define
the document type, dtd, relaxng, xsd, etc.) is an add-on, and a runtime mechanism.

If people want to map some specific (X)Schema to the C++ type system, let them
do that, on top of boost.xml.

Regards,
                Stefan

-- 
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