Re: CLOS Properties Question

From: Christopher C. Stacy (cstacy_at_news.dtpq.com)
Date: 05/15/04 

Date: Sat, 15 May 2004 18:18:50 GMT

>>>>> On Fri, 14 May 2004 08:55:57 -0700, Ari Johnson ("Ari") writes:

 Ari> Christopher C. Stacy wrote:
 Ari> You're not giving anything but ad hominem arguments.
 Ari> I'd be interested in hearing your real logic on this, because I do
 Ari> happen to have a working mind of my own, and I do happen to
 Ari> believe that a clean and complete interface should be the only
 Ari> thing exposed by a package to outside packages.
>> I'm sure anyone would agree, but not absolutely. Search this
>> newsgroup on Google for discussions about "sealing" and "package
>> locking".

 Ari> I'll look into that, thanks.

>> But more to the point: if you publish your interface (through the
>> package system, and more importantly through documentation that says
>> what the interface is), why do you need for the language to further
>> enforce it? Wouldn't it be better to leave the emergency escape
>> hatch, in case you hadn't perfectly thought of everything?
>> Can you provide a real example where this is a problem?

 Ari> Yes: It's a problem when anyone uses my package outside the
 Ari> scope of its interface and then comes knocking on my door when I
 Ari> change the implementation and their code no longer works.

Presumably you are charging them money for this support contract,
so they're just paying you for your time to tell them, "You are
not calling the published interface, and what you are doing is
not supported," I would make sure to charge them a lot.