Re: fyi, very interesting Ada paper OOP vs. Readability

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Fri, 11 May 2012 02:32:09 -0500, Nasser M. Abbasi wrote:

>> P.S. There is no data without types.
> 
> I think the functional programmer guys will not be happy to
> hear this.

No less as I am unhappy with functional programming... (:-))

BTW, there is a pun in the name. Functional programming is non-functional
in its core as it strives to remove side-effects while the only purpose of
any computing is side-effects. (:-))
 
> For example, I use Mathematica, and in Mathematica, there is no
> data types.  Only expressions. There are transformation
> rules to transform an expression from one form to another.

Yes, but as mathematicians have learned a century ago this approach does
not work. You cannot take an axiomatic set theory and the proceed like
1={}, 2={{}}, 3={{{}}}... coming to integer arithmetic, real numbers,
functional analysis (Hilbert's program). That does not work even
theoretically in much more powerful models than pitiful FSA, our computers
are.

A type gives you an opportunity to jump over all constructivist's
nightmares. You just define a type Employee and do not care to play God
creating real employees. That is the power of abstraction. Yes, there is a
price to pay. You have to define operations on Employee, you cannot get
them as theorems in the process of construction. This is what typing is all
about.

> But I think in the world of OO and procedural programming, what
> you are saying makes sense. One defines a type, then declares
> a variable of that type. i.e. data (i.e. variables) always has
> a type.  But I do not think this is the case for all programming
> languages?

This is THE case for whole mathematics since Bertrand Russell's time.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de