Used to represent a logical NOT in the query tree.
Allows us to perform operations over the clauses based on the passed in visitor. This method calls the
visit method on the visitor with this reference.
||the visitor to accept.
- the result of the visit operation who's type is specified by the incoming visitor.
The name of the individual clause, this should be unique amongst the implementations otherwise
the clauses will be treated as the "same" type of clause.
- the name of the individual clause.