Re: anyone define port types?

[Jan Wedekind <jan@wedesoft.de>]

On Wed, 30 Mar 2016, Marko Rauhamaa wrote:

> Panicz Maciej Godek <godek.maciek@gmail.com>:
>
>> 2016-03-30 13:18 GMT+02:00 Jan Nieuwenhuizen <janneke@gnu.org>:
>>
>>> Panicz Maciej Godek writes:
>>>
>>>> I also used GOOPS, which I regret to this day, and so the
>>>> whole framework needs a serious rewrite
>>>
>>> What is it that you do not like about GOOPS?
>>
>> Most specifically, I dislike its middle three letters. The problem
>> with OOP is that it requires to know exactly what ones want -- it is
>> difficult to change the design of your program after it's been written
>> (and it is also difficult to come up with a good design from the
>> beginning), and -- since it is based on state mutation - it makes it
>> difficult to reason about your program.
>>
>> On the practical side, it was a bit counterintuitive that <uvec> and
>> <vector> were unrelated, and I think that there were some issues with
>> <pair> and <list> types.
>
> I like OOP, only I don't like GOOPS. Its classes and generic functions
> seem so idiomatically out of place, unschemish, if you will.
>
> This is how OOP ought to be done:
>
>  <URL: https://www.gnu.org/software/guile/manual/html_node/OO-Closure.htm
>  l#OO-Closure>
>
> I have created a tiny Guile module ("simpleton") that generalizes the
> principle. In particular,
>
> * You don't need classes for OOP. You only need objects.
>
> * Do tie methods to objects. Don't pretend methods are external to
>   objects.
>
> * Don't expose the internal state of objects. Only interact with the
>   object through methods.
>
>
> Marko

GOOPS supports "open" classes and multiple-dispatch. E.g. you can extend 
the "write" method to control how an object is displayed within the Guile 
REPL [1]. Another interesting approach are multi-methods in Clojure which 
don't even require explicit types for dispatching.

[1] http://wedesoft.de/oop-with-goops.html