Re: General semantics

From: Erwin <e.smout_at_myonline.be>
Date: Sat, 22 May 2010 16:20:20 -0700 (PDT)
Message-ID: <b6a0bfc5-4219-4333-b40c-b55c683ac797_at_r9g2000vbk.googlegroups.com>



On 23 mei, 00:33, Clifford Heath <n..._at_spam.please.net> wrote:

> It doesn't have the Aisle/Bin thing, but it has many similar cases.

Does it have cans of cat food ?

I raise the issue because it is such a popular item in any discussion concerning that overhauled OO notion of "identity".

And I'd like to draw attention to a business object that is extremely similar in nature to the cans of cat food : bills of money.

100 dollar bills (and bills of just any quantity of currency unit in any conceivable currency unit, in fact) are uniquely identified by their serial number. However, they also have a property of being "fungible", meaning, essentially, that "if you need 100 dollars, whereever, whenever, for whatever reason, then _any_ 100 dollar bill will do". Or, in other words, the identity of the bill you actually use to pay is completely irrelevant.

Cans of cat food can be identified solely by their location in 3D space. However, noone cares a fucking shit which particular can it was that any customer took from the shelf. Or, iow, for cans of cat food, identity doesn't matter either.

Now, typical OOP systems take identity as a foundational concept, meaning no more and no less than that they are inappropriate to address any problem where "identity really doesn't matter". Received on Sat May 22 2010 - 18:20:20 CDT

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