An operation that will find the geometric difference of one polygon from another.
 [ContractVerification(false)] // TODO: remove when CC bugs are fixed
 internal PolygonXorOperation(PolygonDifferenceOperation differenceOperation, PolygonUnionOperation unionOperation) {
     _differenceOperation = differenceOperation ?? DefaultDifferenceOperation;
     _unionOperation = unionOperation ?? DefaultUnionOperation;
 }
 [ContractVerification(false)] // TODO: remove when CC bugs are fixed
 internal PolygonXorOperation(PolygonDifferenceOperation differenceOperation, PolygonUnionOperation unionOperation)
 {
     _differenceOperation = differenceOperation ?? DefaultDifferenceOperation;
     _unionOperation      = unionOperation ?? DefaultUnionOperation;
 }
 static PolygonXorOperation() {
     DefaultDifferenceOperation = new PolygonDifferenceOperation();
     DefaultUnionOperation = new PolygonUnionOperation();
 }
 static PolygonXorOperation()
 {
     DefaultDifferenceOperation = new PolygonDifferenceOperation();
     DefaultUnionOperation      = new PolygonUnionOperation();
 }