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Re: relations aren't types?

From: Costin Cozianu <c_cozianu_at_hotmail.com>
Date: Mon, 29 Dec 2003 14:54:52 -0800
Message-ID: <bsqbd6$cd9b$1@ID-152540.news.uni-berlin.de>


Bob Badour wrote:
> "Marshall Spight" <mspight_at_dnai.com> wrote in message
> news:uwPHb.66027$VB2.129057_at_attbi_s51...
>

>>"Bob Badour" <bbadour_at_golden.net> wrote in message

>
> news:J8ednZnlZMCYJ3KiRVn-tA_at_golden.net...
>
>>>"Marshall Spight" <mspight_at_dnai.com> wrote in message
>>>news:cNKHb.64146$VB2.125134_at_attbi_s51...
>>>
>>>>"Bob Badour" <bbadour_at_golden.net> wrote in message
>>>
>>>news:MPOdnepoTvzeP3OiRVn-hA_at_golden.net...
>>>
>>>>>Sorry. Time is just as atomic as any other type including relation
>>>
>>>types.
>>>
>>>>I'm not clear on why types have to be atomic. I have not seen a
>>>>reason for it.
>>>
>>>It is not a question of whether they have to be. They just are. The

>
> value 5
>
>>>does not change when we represent it as 5+0j where j is the imaginary

>
> unit.
>
>>I agree that type integer is atomic.

>
>
> The point is all types are atomic. A value is just a point in some space. It
> doesn't matter whether the value is 5+0j or 5+10j or a relation.
>
>

Some types are atomic, or primitives and some types are composite, because they are constructed with compositional means, and they can be *deconstructed* into their components.

For example a tuple type will always be composite and never primitive.

The elementary test of "atomicity" is whether you can decompose a value of that type into its components. Received on Mon Dec 29 2003 - 16:54:52 CST

Original text of this message

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