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Subject: Re: multiple aggregates of same class
From: Olivier Barreteau (olivierb@MIT.EDU)
Date: Tue Feb 24 2009 - 20:57:09 CET
muito obrigado Pedro!
até logo!
Olivier
Pierre Bommel <bommel@cirad.fr> a écrit :
> Prezado Olivier,
> In Cormas, an entity belongs to only one aggregate of a given type :
> An instance of Aggregate is a spatial entity made of (connected)
> components that have been aggregated because they verify a condition.
> For ex, a wood can be an aggregate of entities (Cell or other type of
> spatailEntity) covered by the same cover (Tree). In this case, the
> cell of trees can belong to only one aggregate (Wood).
> If you want that one Cell belongs to 2 or more aggregates at the same
> time, you should have some layers of aggregates. For ex, you may have
> a "cover" and a "landowner" points of view. One given cell may
> belongs to both aggregates at the same time : a Wood
> (VegetationAggregate) and a property (TenureAggregate), as
> illustrated in the following picture :
>
> If you want to use an Aggregate without constraint, you shouldn't use
> the predetermine accessor (theCSE at:) but create a specific accessor.
> All the best,
> Pierre
>
> Olivier Barreteau a écrit :
>> Hi,
>>
>> I would like to be able to control if a given cell is component of several
>> aggregates of the same class.
>>
>> let's say I have cells, which may be part of aggregate entities of class Agg
>> (aCell theCSE at: #Agg) provides only one instance of Agg, and not the
>> collection of all instances of class Agg which contain aCell
>>
>> what happens then if aCell is already component of aAgg and is added
>> to bAgg. To
>> which instance (aCell theCSE at: #Agg) will be referring?
>>
>> best regards
>>
>> Olivier
>> ------------------------------------------------------------------------
>>
>>
>> Internal Virus Database is out of date.
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>>
>>
>
> --
> --------------------------------
> Pierre Bommel - CIRAD - UR Green
> UnB - Faculdade de tecnologia.
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> --------------------------------
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