Emmanuel Pietriga wrote:
> Emmanuel Pietriga wrote:
>
>> David R. Karger wrote:
>>
>>> What happens if various :sublenses invoke each other with different
>>> :depth arguments? Is the semantics that depth is a global variable and
>>> a sublens doesn't apply if the depth exceeds the depth specified for
>>> that sublens? if so, is there any way to specify a "base case", eg
>>> what is going to happen if the sublens cannot be invoked because of
>>> the depth constraint?
>>
>>
>>
>> I have to think about that. Coming back to it later.
>
>
> Depth should be a global variable. Otherwise we do not prevent infinite
> recursion.
>
> Considering the following lens:
>
> :foafPersonDefaultLens rdf:type fresnel:Lens ;
> fresnel:showProperties (
> foaf:name
> [ rdf:type fresnel:PropertyDetails ;
> fresnel:property foaf:knows ;
> fresnel:sublens :foafPersonDefaultLens;
> fresnel:depth "5"^^xsd:nonNegativeInteger ]
> )
>
>
> the lens shows up to five levels of persons. When it arrives at the 6th
> recursive call, it just does not show this property. Nothing else
> happens. We might provide additional Fresnel terms in the extended lens
> vocabulary to say that in this case the browser should show
> links/buttons/whatever/... that make it possible to further explore this
> branch.
>
> The same behaviour applies to recursive calls involving more than one
> lens, knowing that the maximum depth is that declared by the topmost
> sublens call in the recursion.
>
> Ryan, Chris, does this description sound right to you?
Yes, I believe that's how I wrote my code. Although I did realize that
sublenses with maximum depth less than the current depth+original max
depth should be honored, so I'll add that in as well.
--
Ryan Lee ryanlee_at_w3.org
W3C Research Engineer +1.617.253.5327
http://simile.mit.edu/
Received on Mon Jul 11 2005 - 15:16:03 EDT