Got it!
Regards,
Kashyap
On Thu, Oct 24, 2019 at 7:46 AM Alexander Burger <a...@software-lab.de>
wrote:
> On Thu, Oct 24, 2019 at 07:16:31AM -0700, C K Kashyap wrote:
> > If I understand correctly - the filter clause is redundant because it
> does
> > not subset the records generated by the generator?
>
> Yes. In this simple case, where we have only a single generator, this is
> correct.
>
> You don't need 'select' then, and could do
>
> : (? @Nr (1 . 2) (db nr +CuSu @Nr @C))
> @Nr=(1 . 2) @C={C1}
> @Nr=(1 . 2) @C={C2}
> -> NIL
>
>
> > When I look at the filter used in app/gui.l I wonder if the filter
> > (range @Nr @@ nr) does anything - I mean, the generator would only
> generate
> > records where nr is in the range - is that not right?
> >
> >
> > (quote
> > @Nr (and *CuSuNr (cons @ T))
> > @Nm *CuSuNm
> > @Tel *CuSuTel
> > @Plz *CuSuPlz
> > @Ort *CuSuOrt
> > @Mob *CuSuMob
> > (select (@@)
> > ((nr +CuSu @Nr) (nm +CuSu @Nm) (tel +CuSu @Tel)
> > (plz +CuSu @Plz) (ort +CuSu @Ort) (mob +CuSu @Mob) )
> > (range @Nr @@ nr)
> > (tolr @Nm @@ nm)
> > (fold @Tel @@ tel)
> > (head @Plz @@ plz)
> > (part @Ort @@ ort)
> > (fold @Mob @@ mob) ) ) )
>
> No, because the other generators will well find objects with number
> outside the
> range. This assumes the general case, with search criteria also in *CuSuNm,
> *CuSuTel, etc.
>
> If only *CuSuNr were given, and the other criteria were all NIL, then
> indeed
> only the 'nr' tree would be searched, and the range check would be
> unnecessary.
>
> We can say that the generators produce a logical OR of the criteria ("find
> all
> objects that have a number in the *CuSuNr range, OR have a name matching
> *CuSuNm, OR match *CuSuTel" and so on), and then the filter clauses do a
> logical
> AND on the found items ("return only those whose number is in the range AND
> whose name matches *CuSuNm AND whose telephone fits *CuSuTel" etc.)
>
> ☺/ A!ex
>
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