public BaseSpecifications <T> Or(BaseSpecifications <T> specification)
 {
     return(new OrSpecification <T>(this, specification));
 }
 public OrSpecification(BaseSpecifications <T> left, BaseSpecifications <T> right)
 {
     _right = right;
     _left  = left;
 }
 public BaseSpecifications <T> And(BaseSpecifications <T> specification)
 {
     return(new AndSpecification <T>(this, specification));
 }