Re: An object-oriented network DBMS from relational DBMS point of view

On 19 mar, 16:48, "Daniel" <danielapar..._at_gmail.com> wrote:

> I hope you agree that the concept of an instance of an ADT is
> absolutely clear.

"Instance" is a synonym of "object" and it has the very same fuzziness.

I think that "instance" is a lot worse than "object". Object could be acceptable as a truly synonym of "value".

"To instantiate" means to give an example, and it is not an apt for mathematics term.

> The only
> issue as far as I can see is how we relate the term "instance" to the
> terms "value" and "variable". I think it's generally stated that an
> "instance" is a value. Do you disagree?

Completely. I have readen "instance creation" plenty of times and values can't be created.

Let's see the Java spec again:

"A class instance is explicitly created by a class instance creation expression"

Like:

Point point = new Point(0, 0);

Here we have created a variable (instance) named "point" assigning the "ethernal" value Point(0, 0) to it.

"point" is an object. Isn't it?

> Maybe you can clarify, is "value" typically taken as a primitive
> concept, or can it be defined axiomatically?

Primitive.

Regards
  Alfredo Received on Mon Mar 19 2007 - 19:01:00 CET