[lextypes] Holus bolus: a general-purpose datatype library

[John Cowan]

Jeni Tennison scripsit:

> I'm not going to comment on the suitability of these types for XML,

Foo.  I had particularly hoped for your input on that very point.

> The biggest thing that I notice is that parameters in Holus Bolus
> perform several different roles, only one of which is supported
> through parameters in DTLL. The roles that I can see, and the
> parameters that take on these roles, are:

I really like this classification.

> 1. validation of lexical representations:
> 2. interpretation of lexical representations (to give a value):
> 3. validation of values:
>    - boolean/truereps
>    - boolean/falsereps

I think these two belong under 2.

> 4. interpretation of other parameters:
> 5. manipulation of values:
> 
> As far as parameters that determine how
> other parameters are interpreted (4) goes, I'd assumed that you'd use
> different names for parameters to be interpreted in different ways
> (e.g. minInclusive + minExclusive rather than minimum + minimumKind).

My concept here, which is not actually explained anywhere, is to make the
parameters independent.  In WXS2, you can't have both maxExclusive and
maxInclusive parameters.

> I think that it would be possible to alter DTLL to support all these
> different kinds of parameters, by creating a more general
> parameterisation mechanism used to set the values of variables used in
> XPaths etc. But I wonder whether it would be worthwhile placing
> restrictions on what's parameterisable?

I think it is worthwhile, but I think all the parameter types above are
worth having in some sense.

-- 
Eric Raymond is the Margaret Mead               John Cowan
of the Open Source movement.                    jcowan at reutershealth.com
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