[plt-scheme] Lightweight object system

From: Noel Welsh (noelwelsh at gmail.com)
Date: Wed Sep 5 06:55:54 EDT 2007

On 9/4/07, Dave Griffiths <dave at pawfal.org> wrote:
> But it seems there are multiple object systems to choose from - do they
> fill different niches, or is this considered a problem? (i.e. portability
> of code between different object systems).

They do fulfill different niches to some extent, but my advice is to
use the 'native' object system of whichever implementation you
primarily use.  I'm amazed and baffled that people can get useful work
done in portable Scheme.

> To put it another way - will an object system ever be part of RnRS, or is
> this verging on heresy ;)

Given sufficient time all possibilities occur. :)

The Scheme world is currently in a very interesting situation -- the
new standard has  significantly enlarged its scope, making it much
more useful for writing practical code and allowing greater
portability.  It remains to be seen how quickly R6RS will be adopted
and what impact it will have on implementations, but I think it is now
conceivable that the main Scheme impls will converge to the state
where a standard object system is possible, whereas I would have
considered this impossible pre-R6RS.

Object systems themselves are contentious but languages that are
exploring functional/OO hybrids (PLT, Oz, Scala, O'Caml) seem to have
some broad similarities in their object systems so I believe consensus
is possible.


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