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Re: Example of expression bias?

From: Cimode <cimode_at_hotmail.com>
Date: 20 Jun 2006 23:40:45 -0700
Message-ID: <1150872045.644023.28740@g10g2000cwb.googlegroups.com>

Tony D wrote:
> J M Davitt wrote:
> > CJD calls them type constraints; they define the set of values
> > that constitute the type. Types are named, so the sets are named.
> >
> > The only thing I'd argue about in Cimode's definition is that
> > operators are part of the data type. In fact, D+D make the point
> > that the declaration of operators is orthogonal to the declaration
> > of types -- given that the types are extant before the operators.

> The issue I had with the long-form of Cimode's definition is that he
> takes domains to be separate from types; IIRC, to Cimode, domains are
> sets of all possible values, and a given type restricts which of the
> possible values from the domain are acceptable for that type (I'm sure
> he'll correct me if I have misrepresented his position in any way). I
No you understand right what I have stated.(Finally) It is not that data type is separate from domain, definition of data type is separate from domain definition...data type is derived from domain by restriction on permissible values.

> stuck with the type simply defining the acceptable values either
> explicitly by enumeration or by equations to describe the set. I'm open
> to convincing, but at the moment I'm not. (I have an argument that says
> a particular value belongs to a single type only, but that might kick
> off and it's now 3:20am, so I'm off to bed :)
It seems after 3 hours discussing, that you begin to get the RM definition of a relationship between a data type and domain. Received on Wed Jun 21 2006 - 01:40:45 CDT

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