[lextypes] DLL proof of concept

[Bob Foster]

> > - A reference implementation that accepts every valid definition and
rejects
> > every invalid definition (that is defined as required to be reported,
> > according to the spec).
>
> For sure.
>
> > - An implementation that converts a valid definition to a form that
allows
> > it to be used with one or more existing schema languages such that a
value
> > is declared valid if and only if it conforms to the DLL definition.
>
> In present practice this would mean providing an RNG datatype library
interface.

Maybe a Schematron implementation is possible, too? An XML Schema
implementation couldn't pass the test. (It is not even possible at the
moment to translate a DTLL definition of the XML Schema datatypes into XML
Schema unless there were a way to associate DTLL parameter names, which have
no intrinsic meaning, with facets.)

> See below.
>
> > - A language-independent API specification and an implementation in one
or
> > more existing programming languages that allows, at a minimum, an
> > application to ask, for any string value, whether it is a valid instance
of
> > a given datatype, and if so, to obtain the parse result. The API should
be
> > able to operate independent of validation.

You didn't comment on this and I kind of think it may be the most important
one. ;-} Any particular reason why?

[good info about RNG omitted]

Bob Foster