Re: terminology

From: Marshall <>
Date: 18 Jun 2006 14:30:37 -0700
Message-ID: <>

paul c wrote:
> Marshall wrote:
> > paul c wrote:
> >>...
> > Certainly there are different contexts in which the term "variable"
> > is used, and across those different contexts there may be
> > incompatible meanings. I was speaking of the programming
> > languages theory ("PLT") context. So I am speaking of regular
> > data variables, rather than logic variables--they are quite
> > different.
> > ...
> Okay, not trying to give you a hard time,

Didn't think you were; thought you made a valuable point.

> as I liked the economical
> phrasing, it was just that the start of the original msg mentioned "in
> the c.d.t. context" and i feel a conventional programming language
> must be a mere servant of that.

You know, it's funny you should mention that.

After responding to your last post, it got me thinking about how RT and PLT fit together. It occurred to me years ago that the RA would be an extremely useful addition to a general purpose programming language, and later, reading TTM, it was clear that others had already had the same idea.

TTM is extremely well developed in the RT part. Indeed, it is the most thorough treatment of the topic I know of, and probably the only one to give it its due importance. But it is fairly uninspired in the PLT part. There is no mention of closures (in the PLT sense,) lambda, higher-order functions, recursion or tail-call optimization, process calculi or even message passing, type inference, parametric polymorphism (outside of its built-in use with relations) or metaprogramming anywhere in the book that I can find. (Although I only have the 2nd ed.; haven't gotten to the 3rd ed. yet.)

The thing is, I think the goal (or at least *a* goal) is to produce a great general-purpose programming language with first-class support for RT. I don't think that producing a relational algebra system with support for general purpose computation is quite as interesting. So in that sense, I think what I really want to see is RT embedded into PLT, and not the other way around, although I agree that the RT part is foundational and therefor crucial.

Marshall Received on Sun Jun 18 2006 - 23:30:37 CEST

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