constraints and context

[son-of-sargasso]

(Going back a couple of posts here, bear with me)

I was just saying that constraints on attributes as we model from the generic to the specific, tend to become more and more specific.  Generic was probably a bad term there, when we model from the business to the technology would have been better.  

Constraints on a business object (classifier) become less and less rational as we move into the OO "cleanroom".  I always prefer to put the constraint "at the lowest applicable level" because these aspects tend as the model progresses to get more and more "cleaner" i.e. the "L.A.W." of the constraint becomes both easier to crystalise and later on easier to justify (in the positve sense).  

I was implying by "higher/lower" from the world to the code, not from the specific to the generic as in attribute to datatype.

Anyway.  I like Geert's "rules" but I think an interclass constraint really should be taken out the back door, shot and given a quiet burial.  I mean any class "Fish" that depends on the constraints of class "Bicycle" is just gonna get into a hell of a lotta arguments.

bruce

[Paolo F Cantoni]

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Anyway.  I like Geert's "rules" but I think an interclass constraint really should be taken out the back door, shot and given a quiet burial.  I mean any class "Fish" that depends on the constraints of class "Bicycle" is just gonna get into a hell of a lotta arguments.

bruce

You can have inter-class constraints when the constraints on "Fish" depend upon the values (not constraints - typo?) of a mandatorily related "Bicycle".

But, in general, inter-class constraints should be views as potential constraint "smells".

Paolo

[Paul Lotz]

Geert,

I agree sometimes a document is necessary to convey all the information, but for our current purposes the diagrams are actually more digestable for the reader and convey all the information required suitably except for constraint information on attributes.  I suggest it would be nice to have this information more accessible in EA in any case.

Paul