class point
// A point in two-dimensional space
    {
    double x,y;
    }

class animal
// Base clase for animals
    {
    morph flow name() into string name {name = "animal";}
    morph flow dims() into point p {p = (1,1);}
    }
animal animal = ();

class zebra extends animal
    {
    morph flow name() into string name {name = "zebra";}
    morph flow dims() into point p {p = (4,5);}
    }
zebra zebra = ();

class frog extends animal
    {
    morph flow name() into string name {name = "frog";}
    }
frog frog = ();

flow distance(point a, point b) into double d
    {
    double dSquared;
    double dx = a.x - b.x;
    double dy = a.y - b.y;
    dSquared = dx*dx + dy*dy;
    d = sqrt(dSquared);
    }

array of int arr = (1,2,3,4);

to printInfo(animal a)
    {
    int b = 3;
    prin(a.name());
    prin(" ");
    print(a.dims());
    arr[b] = 666;
    }

printInfo(animal);
printInfo(frog);
printInfo(zebra);
prin("frog to zebra difference ");
print(distance(frog.dims(), zebra.dims()));