On 2012-02-04 13:06, Simen Kjærås wrote:
It seems that what you want is alias this:

Thank you both, that's exactly what I needed.

Leeching a bit more on the thread:
Going back to the method:
int somethingNifty(Point p) {
  return p.x + p.y;
}

Let's say I have the following code:
for (x; 0 .. 10) {
  for (y; 0 .. 10) {
    Point p = {x, y};
    somethingNifty(p);
  }
}

[How] can you rewrite those two statements inside the loops to a single line? For example (this doesn't work):
somethingNifty(Point(x, y));


And finally a question about operator overloading, here's the code for "Coordinate" ("Point" is similar in structure):
import Point;
struct Coordinate {
  Point _point;
  int _z;
  @property auto point() const {
    return _point;
  }
  @property auto point(Point point) {
    return _point = point;
  }
  @property auto z() const {
    return _z;
  }
  @property auto z(int z) {
    return _z = z;
  }
  bool opEquals(ref const Coordinate c) const {
    return z == c.z && point == c.point;
  }
}

Compilation fails with the following error:
Coordinate.d:18: Error: function Point.Point.opEquals (ref const const(Point) p) const is not callable using argument types (const(Point)) const
Coordinate.d:18: Error: c.point() is not an lvalue

Noteworthy the code compiles fine if i replace "point" and "c.point" with "_point" and "c._point", but then I'm referencing _point directly instead of through the property "point" (which may do something else than just return _point in the future). I've looked at http://www.d-programming-language.org/operatoroverloading.html#equals and that page is slightly confusing. It claims that: If structs declare an opEquals member function, it should follow the following form:
struct S {
  int opEquals(ref const S s) { ... }
}

However, I can't even get the code to compile if I do that, the compiler (gdc-4.6) says: Error: function Coordinate.Coordinate.opEquals type signature should be const bool(ref const(Coordinate)) not int(ref const const(Coordinate) c)


I hope it's somewhat clear what I'm trying to achieve.

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