anchor.diff:    void initTests() {
       // do some funky stuff
       p0 = new Alg.Point3D.zero();
  -    p1 = new Alg.Point3D(1,2,3);
  -    p2 = new Alg.Point3D(4,-5,7);
  -    v1 = new vec3.raw(1,-2,5);
  -    v2 = new vec3.raw(-1,0,-7);
  +    p1 = new Alg.Point3D(1, 2, 3);
  +    p2 = new Alg.Point3D(4, -5, 7);
  +    v1 = new vec3.raw(1, -2, 5);
  +    v2 = new vec3.raw(-1, 0, -7);
  +
  +    iNull1 = new Alg.Interval(0, 30);
  +    iNull2 = new Alg.Interval(-20, 0);
  +    iPos = new Alg.Interval(2, 7);
  +    iNeg = new Alg.Interval(-5, -1);
  +    iZero = new Alg.Interval(-1, 1);
  +    iEmpty = new Alg.Interval.empty();
  +
  +    i = new Alg.Interval(0.00002, 300);
     }
   
     /*
  
positive.code:     expect(lerped.z, closeTo(5.36, EPS));
    }
  
    //TODO interval tests
    intervalCreation() {
      throw new UnimplementedError();
    }
  
    intervalArithmetic() {
      throw new UnimplementedError();
    }
  }
negative.code:    */
    Alg.Point3D p0,p1,p2;
    vec3 v1,v2;
    Alg.Interval i, iNull1, iNull2, iPos, iNeg, iZero, iEmpty;
  
    // Tests the expected state after point creation.
    pointCreation() {
  