Re: Returning structures to Prolog from C code

[FORT David]

Vic Bancroft wrote:

> On Wed, 5 Dec 2001, FORT David wrote:
>
> > I see strange things when i try to return structures to prolog from C
> > code, here's some the samples:
> >
> > implementation in C:
> >  ...
> >  functor_atom = ATOM_CHAR(',');
> >  ...
> >  tmp = Mk_Compound( functor_atom, 3, (PlTerm *)&args );
> >  ...
> > Here i'd expect (ip,'192.168.4.134',new) instead of
> > ','(ip,'192.168.4.134',new)
>
> You specifically asked for the atom ',' to be the functor for the compound
> term, did you intend to construct a list instead ?
>
> In that case, you might have been thinking of the '.' list constructor.
>
> A prolog list, [ ip, '192.168.4.134', new ], would really be the same as,
>
>  | ?- X =  '.'(ip, '.'('192.168.4.134', '.'( new, [] ) ) ).
>
>  X = [ip,'192.168.4.134',new]
>
> So instead,  you might use, "Mk_Proper_List( 3, (PlTerm *)&args )" 
>
> more,
> l8r,
>
> -------------------------------------------------------------------
> Victor Bancroft
> Fellow, Artificial Intelligence Center               (706) 542-0358
> Athens, Georgia  30602, U.S.A           http://ai.uga.edu/~bancroft
> Principal Engineer, Zvolve Systems                  [v]770.551.4505
> 1050 Crown Pointe Pkwy, Suite 300, Atlanta GA 30338 [f]770.551.4509
Definitly not,[ip,'192.168.4.134',new] and (ip,'192.168.4.134',new) are not
the same. For example you can't match with (ip,X, Y) if it's a list.

address@hidden gave me the REAL solution: when i write
(ip,'192.168.4.134',new) i should have understand 
','( ip, ','('192.168.4.134',new) )

Mk_Proper_List does this with a list, i think a Mk_Proper_Compound is
really missing here.

--
-- FORT David - address@hidden --
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