Constructs a new immutable, finite relation that is initially empty.
Constructs a Relation from underlying forward
and reverse
representations, without checking that they are consistent.
Constructs a Relation from underlying forward
and reverse
representations, without checking that they are consistent.
This is a low-level constructor and the alternatives empty and reconstruct should be preferred.
Constructs a relation such that for every entry _1 -> _2s
in forward
and every _2
in _2s
, (_1, _2)
is in the relation.