InterfereRelation

Add a collection of b elements to a Warning if the b is empty then all the element linked to a are removed (STRANGE)

Add the element b to a

Provide the elements in relation with a WARNING the function returns an empty set either if a is not in the relation or if no elements are associated to a

Provide the set of all input elements

Provide the relation a map of edges

Provide the elements in relation with a id a is in the relation

Provide the elements a in relation with b

Remove a from the relation WARNING: this is different from removing all elements in relation with a

Remove the elements of the collection b from the relation with a

Remove the element b from the relation with a

Provide the set of all output elements