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Re: why hierarchy?

From: Neo <neo55592_at_hotmail.com>
Date: 31 Jul 2006 18:31:50 -0700
Message-ID: <1154395910.216505.45150@i42g2000cwa.googlegroups.com>

> > (new '10/12/1993 'date)      Note: date modelled in simplified manner.
>
> Let me guess. The date  '10/13/1993 ' would be
>
> (new 'as)
> (new 'successor)
> (create date '11/12/1993' as successor of 10/12/1993)

While user knows that 10/12/1993 implies month 11, day 12 and year 1993; to allow app to determine this systematically, it should be modelled as below:

(new 'date)
(new 'month)
(new 'day)
(new 'year)

(new)
(create date instance (it))
(create (it) month (val+ '10))
(create (it) day (val+ '12))
(create (it) year (val+ '1993))

Prior expression "(create bob friend tom since 10/12/1993)" becomes:
(create bob friend tom since (and (select date instance *)

                                                 (select * month 10)
                                                 (select * day 12)
                                                 (select * year 1993)))
Received on Mon Jul 31 2006 - 20:31:50 CDT

Original text of this message

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