From: Jared Nuzzolillo Date: 2005-08-17T05:55:45+09:00 Subject: Re: Prototype vs Class inheritance, (was: Ruby for my new business?) ------=_Part_1019_79046.1124225742241 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Jeff, Thanks, I will read it tonite when I get home. Without having read it,=20 though, I can say that I still think of things as Categories in=20 prototype-based languages. For instance, in Io, a create a 'class' with: Dog =3D Object clone Dog speak :=3D method(write("bark")) And then I create individual dogs with: fido =3D Dog clone spot =3D Dog clone spot speak fido speak My point is that I still use the objects as if there were categories and=20 classes of things (eg, you will still find a Button 'class') but that there= =20 are no differences between classes and instances as far as the language is= =20 concerned. But I am sure the author of the paper means something more=20 profound. Thanks again, Jared Nuzzolillo On 8/16/05, Brian Mitchell wrote: >=20 > On 8/16/05, Jeffrey Moss wrote: > > > ...but I still feel that prototype-based languages have a certain > > > conceptual elegance that is lacking in class-based alternatives. > > > > It's interesting the part western philosophy played in language design,= =20 > I > > tend to agree with you about the conceptual nature of class vs prototyp= e > > inheritance, but class based inheritance is easier for me to use, easie= r=20 > to > > lay out in my mind. > > > > Here's an interesting read on the subject: > > http://www.helsinki.fi/~jppesone/papers/kandi.html > > > > Summary: > > From an ontological point of view the prototype-based languages win.=20 > There > > is little evidence of a strange platonic realm of categories, but > > class-based languages don't necessarily have to be realist in their > > ontology - a language can include universals and "Santa Claus" without > > committing to realism (von Wrigth 1972, 198). Unless the prototype-base= d > > languages include some notion of categories they lack something > > psychologically very important: the capacity of categorization. > > > > -Jeff >=20 > Very interesting. Thanks for the link. This is all ironic right now as > I am currently working on implementing a complete Ruby environment > inside/using Io. It has been interesting on how easy it was to lay the > class based design of Ruby over the prototype based Io. I am not quite > done solidifying the final translation between the two but when I get > further I will throw the code up for consumption. >=20 > Sometimes all we need is an initial pattern to help prime the mind. > Then we can go on to clone or copy that pattern into classes or > prototypes. >=20 > Brian. >=20 > ------=_Part_1019_79046.1124225742241--