Re: Storing data and code in a Db with LISP-like interface
Date: Mon, 08 May 2006 17:56:51 GMT
Message-ID: <DDL7g.5112$A26.129543_at_ursa-nb00s0.nbnet.nb.ca>
Dmitry A. Kazakov wrote:
> On Thu, 04 May 2006 23:00:18 GMT, Bob Badour wrote:
>
>>Agreed. However, type theory is not the exclusive domain of OO, and OO >>does it particularly poorly.
>
> That depends. Clearly hyper-inaccessible cardinals are not well handled.
> (:-)) But ADTs have far less problems with set theory as the application
> domain than RM. Trivial examples are:
>
> 1. Power set operation
It is a closure. What makes you think the RM has any problem with it?
> 2. Set complement in an infinite universal set
As soon as you invent an infinite computer, your assertion will have a relevant meaning. In the meantime, how about responding substantively to the points I have already made?
> 3. Infinite sets modeled by finite classes of equivalences
Again, I don't see this as any challenge in the RM. I wonder whatever makes you think it would be?
The whole argument, "hey, we are the set
> theory" is absurd.
Horseshit. I pointed to the foundation of RM in Codd's 1970 paper as a direct application of set theory, and you have failed to point to any similar foundation for OO. You basically ignored everything I wrote responding instead with three false assertions lacking any support, elaboration or substance.
> The meta level (positions 3-) is more interesting. My position is that on
> the meta level RM represents specialized container types.
That's because you are ignorant and too arrogant to admit your ignorance to yourself.
It would be
> interesting first to sink it to ordinary types, to have operations x -> {x}
> ("tables of tables" etc). On the other side it would be interesting to
> leverage it to sets of types, in order to achieve generic programming.
> Instead of cursing, just do it better guys, and we all will see that there
> is no difference between OO and RM.
Your faith is unassailable. However, the RM has already done it better and a huge difference remains--a huge difference that makes OO look sick in comparison.
>>>Should it mean that RM is used to solve set-theoretic problems? Are you >>>guys proving continuum hypothesis in SQL, or what? I take my hat off! Alas, >>>my customers have money for other problems, and navigate other spaces... >> >>They navigate the spaces RM pilots best.
>
> I read it as a confirmation that we can finally bury the corpse of "we are
> the set theory."
I have found that the invincibly ignorant will read whatever they want however they want. Nevertheless, burying your head in the sand won't make Codd's 1970 paper disappear nor will it erase three and a half decades of successfully applying the RM as set theory. Neither will it make any comparable foundation for OO suddenly appear.
>>>>>>A supertype is a superset of values >>>>> >>>>>This is a common misconception. The domain set of a supertype is not a >>>>>subset of the domain set of its subtype. >>>> >>>>No, it is a superset. I thought I was clear on that. >>> >>>OK, you share that misconception. >> >>It is not a misconception. All the values of a subtype are necessarily >>values of the supertype. This makes the supertype a superset of values. >>All of the operations that apply to values of a supertype also apply to >>values of the subtype. This makes the supertype have a subset of operations. >> >>Any type theory that gets the above wrong is for shit.
>
> Where that follows from? In mathematics you can go either way. Is integer
> number rational?
Yes.
How different pairs (1,1),(6,6) can both be 1? Is (1,0i)
> integer? Why should anybody worry about it?
You are confusing representations with values. The pairs only represent 1 assuming they represent rational values as a numerator and a divisor. We can have any number of representations for the same value without changing the value.
>>A screw is an application of the simple machine known as a ramp. It is >>not an application of static analysis; although, one can describe some >>functions of a screw using static analysis.
>
> I can only hope that you don't screw your car with books on static
> analysis!
As much as I like SNL, we are not discussing parody; the Mercury Mistress has no relevance here. The intellectually honest have no need for such evasions.
>>Sorry, you will have to do better than make the assertion. Can you point >>to the set theory Dahl and Nygaard cited in the development of Simula? >>Since the word 'class' came from Tony Hoare's proposal for type-safe >>physical pointers, ie. his proposal for a record class in Algol, perhaps >>you can point to the bibiliography where he cited set theory when >>choosing the name? I could not find a bibliography or even the text for >>that article. >> >>On the other hand, Codd's 1970 ACM paper very clearly shows that the RM >>is set theory and his later work establishes the equivalence between >>that set theory and predicate calculus.
>
> You can google for FOL and OO if you are interested in that stuff. Surely
> any formalization of types systems will position itself relatively to FOL.
Of course, one uses FOL to describe OO and to try (in vain) to give it a better formalism. That's because FOL is such a powerful tool for managing data. However, you won't find that OO was founded on FOL. You won't find that OO is FOL. The RM is FOL as established in Codd's 1971 papers.
>>>>One can apply set theory to describe anything, >>> >>>This is technically wrong. See Hilbert's program. >> >>What about it? Are you suggesting that limitations to a description make >>it any less a description? An incomplete description is still a >>description.
>
> Then you should have formulated it as "to apply X to incompletely describe
> anything." (BTW, when you describe something as "shit" is that a complete
> or an incomplete description? (:-))
It is incomplete. We can count the corns in shit, and otherwise describe minute details. However, if one's primary goal is to avoid stepping in it, the description functions well enough.
>>>>which is why applying it to data management is so >>>>appropriate. Applying set theory to the task of describing some ad hoc >>>>shit doesn't make the ad hoc shit an application of anything. >>> >>>It is an application of and for the ad-hoc shit. Scatology is a science, >> >>Exactly! And that describes OO to perfection.
>
> Hmm, what if anybody would create an RDB of excrements? I am pretty sure
> that paleontologists already did...
If the paleontologists haven't, I am sure the farmers have. Farmers and paleontologists, at least, get real utility from shit. Received on Mon May 08 2006 - 19:56:51 CEST