iterator question.

[Carl Ollivier-Gooch]

Jason Kraftcheck wrote:
> Mark Shephard wrote:
>> The Simmetrix people have been looking at the ITAPS iMesh, iMeshP, iRel
>> and iGeom interfaces.
>>
>> One of the questions they have sent us has to do with iterators and is:
>>
>> "Are iMesh_getNextEntIter and iGeom_getNextEntIter supposed to have the
>> same behavior as their documentation describes two different behaviors -
>> iMesh_getNextEntIter indicates whether the current call returned data
>> (which is fairly standard behavior for an iterator),iGeom_getNextEntIter
>> indicates whether the next call will return data (which is kind of odd
>> behavior for an iterator)."
>>
>> I would think they should have the same behavior and the iMesh behavior
>> is the right one. Comments please.
>>
> 
> I think (if I correctly recall the that group discussion about this) that
> the iMesh one is the correct one.  Returning information about next call, as
> the iGeom one does, is not usable in mesh modification scenarios (consider
> iterator at second to last entity when last entity is deleted.)

Jason has identified precisely the reason that the iMesh iterator 
behavior was changed.

Carl


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