Re: A good book

Chris Smith wrote:

> Bob Badour <bbadour_at_pei.sympatico.ca> wrote:
>

>>Are you suggesting that predicate calculus is just some different tool?

Relational calculus = 1st order predicate calculus

Am I missing something?

> I am, therefore, looking for sources that explain that connection. I
> don't think Dijkstra does (a) except in certain domains that involve
> certain *uses* of predicate calculus to ensure the correctness of
> application code, which are not relevant to databases inr eadily
> apparent ways; and I don't think he does (b) at all. If you disagree,
> I'd like to see a reference... but I've read a good bit of Dijsktra's
> writing, INCLUDING his book "Predicate Calculus and Program Semantics",
> and I haven't seen it; and just "the EWD archives" doesn't point too
> clearly.

Life is too short to go digging for it, but one EWD stands out in regard to elegance where EWD provided a proof without iteration for something previously proved using iteration. He used it as an example of greater elegance.

> I'm not saying these relationships don't exist. Rather, I entirely
> trust that (b) exists, but I don't want to trust people; I want to
> understand the connection. I also think (a) probably exists at least in
> some limited form, limited because of course I can think of all sorts of
> ways to write inelegant code while applying results from predicate
> calculus, and I'd like to understand the relationship better there. I'm
> looking for sources that can explain them so that I understand the
> relationships better.
Received on Sat Jul 08 2006 - 01:06:46 CEST