Tell me more ×  Basically there are three classes I defined:
paralelogram, point and line classes, and paralelogram has some
vectors of points and lines, and in the paralelogram class I am
defining a compute_area function as  double
Paralelogram::compute_area() const   assert( !points.empty() );
double h = points[3].distance_to_line( lines[0] ); // point[3]
is the last point in
// the vector however it is not a
// const object, and this gives a
// compile time error   double base =
points[0].distance_to_point( points[1] );   return base*h;  Edit
distance_to_line function is non-const  double
Point::distance_to_line(Line& l)   return
l.distance_to_point(*this);  deleting the const from the
function definition and declaration solves the problem, however
my reasoning, while coding, was compute_area does not modify the
object so it can be const, however t