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Co-Constraint Dimension: Effect

In message Analysis of use cases for co-constraints Fabio Vitali proposed a set of dimensions for the evaluation of co-constraints use cases. This is an explanation of dimension effect.

Effect: the kind of effect the dependency has on the destination

  • FLAG: Just raise a validation error
  • UPGRADE: Optional structure becomes required, nillable structure becomes non-nil
  • DOWNGRADE: Optional structure must not appear, nillable structure becomes nil
  • MUTUAL PRESENCE: both structures must appear together or none
  • MUTUAL EXCLUSION: either structure must appear, but not both. None appearing is acceptable
  • ALTERNATIVE EXCLUSION: either structure must appear, but not both. One must appear.
  • RESTRICTION: a normally acceptable structure is not acceptable
  • RELAXATION: a normally unacceptable structure is acceptable
  • CHOICE OF TYPE: one of multiple content models is chosen
  • NOT CLEAR: use case does not explain the effect