Re: no names allowed, we serve types only
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 Mon Feb 22 2010 - 05:27:26 CET