Re: singleton variable in branch ?

I must be blind, sometime...So obvious...

I really have another better definition of task at hand, then I didn't
debugged it in any depth...

Thanks all



2014-03-01 9:49 GMT+01:00 Jan Wielemaker <[email protected]>:

> On 03/01/2014 09:27 AM, Jochem Liem wrote:
> > The singleton is in the second branch (subsynset). Adding a '_' makes
> > the warning go away.
> >
> > subsynset(Sub, Super) :-
> >    s(I,_,Sub,Kind,_,_),
> >    (
> >       hyp(I, J) ->
> >       s(J,_,Hyp,Kind,_,_),
> >       Hyp = Super
> >    ;
> >       subsynset(_Hyp, Super)
> >    ).
>
> YIP.  For your understanding, a `singleton in a branch' is a variable
> that is syntactically not a singleton (appears in multiple places in
> the term), but does not transfer a binding from one goal-argument to
> another.  That turns it in to `a semantic singleton'.  If anyone has
> better wording for this warning, please share it.  Do take them
> seriously; in my experience well over half of them indicate real
> bugs.
>
>         Cheers --- Jan
>
> >
> > - Jochem
> >
> > On Sat, Mar 1, 2014 at 9:37 AM, Carlo Capelli <[email protected]>
> wrote:
> >> I get a warning in very simple code - Singleton variable in branch: Hyp
> >>
> >> and I can't spot from where the problem arise.
> >>
> >>
> >> subsynset(Sub, Super) :-
> >>
> >>  s(I,_,Sub,Kind,_,_),
> >>
> >>    ( hyp(I, J) -> s(J,_,Hyp,Kind,_,_), Hyp = Super
> >>
> >>   ; subsynset(Hyp, Super)  ).
> >>
> >>
> >>
> >> I tried to swap the Hyp binding - just to see if the warning goes away -
> >> without luck
> >>
> >>
> >> ...
> >>
> >> -> s(J,_,Hyp,Kind,_,_), Hyp = Super
> >>
> >> ...
> >>
> >>
> >> Seems that Hyp is present on both branches. Maybe I'm missing some
> >> execution path ? Any hint about ?
> >>
> >>
> >> Thanks Carlo
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> >
> >
>
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