How is this code supposed to work?

[AndreasDavour via Digitalmars-d-learn]

I'm reading the "Programming D" here:
http://ddili.org/ders/d.en/templates.html
and am a bit confused by the section on templates.
with a struct template like this:
struct Point(T) {
  T x;
  T y;

  T distanceTo(Point that) const {
    immutable real xDistance = x - that.x;
    immutable real yDistance = y - that.y;

    immutable distance = sqrt((xDistance * xDistance) +
                              (yDistance * yDistance));
    return cast(T) distance;
  }
}

and a function template like this:
Point!T getResponse(T : Point!T)(string question) {
    writefln("%s (Point!%s): ", question, T.stringof);

    auto x = getResponse!T(" x");
    auto y = getResponse!T(" y");

    return Point!T(x, y);
}

How am I supposed to use that??

  auto point3 = getResponse!Point!int("What's the point? ");
  auto point4 = getResponse!Point!int("What's the point? ");
  writeln("Distance: ", point3.distanceTo(point4));

generates the error:

struct_templates.d(48): Error: multiple ! arguments are not 
allowed
struct_templates.d(49): Error: multiple ! arguments are not 
allowed

Which makes me wonder about the syntax.