Re: No exceptions?
Date: Thu, 29 Jun 2006 21:07:49 GMT
Message-ID: <FiXog.1332$u11.438_at_tornado.ohiordc.rr.com>
paul c wrote:
> J M Davitt wrote:
>
>> paul c wrote: >> >>> Bob Badour wrote: >>> ... >>> >>>> The way to avoid exceptions is to treat them as compile-time errors. >>> >>> >>> >>> I take it you really mean "ONE way to avoid exceptions ...". For one >>> thing, I am interested in being able to express "x join y" in advance >>> of defining a header for "x" (and I would like to evaluate it as well >>> if that is logically possible!). >>> >>> p >> >> >> This has me scratching my head. Without a heading, there can be no >> parameters. Without parameters, there can be no arguments. Without >> arguments, there can be no quantifiable proposition. Which leads me >> to, "A relation without a predicate is... What?" I find this >> especially curious because you mention the Closed World Assumption >> in the same post. (Don't forget the Excluded Middle!) >> >> So, Paul, what are you trying to explore?
>
>
>
> Maybe instead of saying "defining a header", I should have said "in
> advance of entering a header". I had in mind that an "empty" header
> would be assumed.
Empty heading: like DEE and DUM have empty headings?
> My peculiar view doesn't require me to ask "what is the predicate of
> such and such a relation". This will sound ridiculous to most people I
> think because one would ask "well, what good is a database whose
> predicates we don't know?". OTOH, one aspect that for me defines a
> relational engine is precisely that it must not circumscribe even in the
> most indirect of ways what predicate a particular relation has, its
> whole value is in being to manipulate relations without knowing that -
> otherwise it would be an application!
It almost seems as though you want to declare an analogue for DUM, syntax-check some expressions, and add attributes to your relation with the confidence that your expressions are still correct.
> Apologies if this is metaphysical mumbo-jumbo. Will ponder the CWA and
> excluded middle again.
>
> p
Received on Thu Jun 29 2006 - 23:07:49 CEST