Re: no names allowed, we serve types only

From: Gene Wirchenko <genew_at_ocis.net>
Date: Sun, 21 Feb 2010 20:27:26 -0800
Message-ID: <ol14o5lspskhp76tnshm57v6v94ps4oc0i_at_4ax.com>



On Fri, 19 Feb 2010 08:36:58 -0800 (PST), Kevin Kirkpatrick <kvnkrkptrck_at_gmail.com> wrote:

[snip]

>Dave, could your SUPPLIERLOCATIONCITY vs SUPPLIERDISPATCHCITY (and
>other such objections) be resolved by having two kinds of subtyping -
>one allowing implicit coersion and the other not - e.g.
>
>TYPE CITYNAME SUBTYPE STRING EXPLICIT COERSION
>TYPE SUPPLIERLOCATIONCITY SUBTYPE CITYNAME IMPLICIT COERSION
>TYPE SUPPLIERDISPATCHCITY SUBTYPE CITYNAME IMPLICIT COERSION
     I think that this level of typing is silly. *Every* column has its own type? Is there really any difference between a SUPPLIERLOCATIONCITY and a SUPPLIERDISPATCHCITY? (If they have the same operations, what is the difference?)

     I think this would be more useful:

          TYPE CITYNAME SUBTYPE STRING EXPLICIT COERSION
          column SUPPLIERLOCATIONCITY isa CITYNAME
          column SUPPLIERDISPATCHCITY isa CITYNAME

[snip]

Sincerely,

Gene Wirchenko Received on Sun Feb 21 2010 - 22:27:26 CST

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