Class operators in Freepascal records like in Delphi 2010?

**paul_nicholls** · 15-04-2011, 04:16 AM

Hey all,
I was wondering if it is possible to use records in Freepascal (Lazarus 0.9.30, Win32) with class operators now like Delphi 2010?

Code:

interface

type
  TVector2f = record
  public
    x, y: Single;
    class operator Negative(const v: TVector2f): TVector2f;
    class operator Add(const v1, v2: TVector2f): TVector2f;
    class operator Subtract(const v1, v2: TVector2f): TVector2f;
    class operator Multiply(const v: TVector2f; const s: Single): TVector2f;
    procedure SetValue(const aX, aY: Single);
    function Normalize: TVector2f;
    function Len: Single;
    function Dot(const v: TVector2f): Single;
    function Perp: TVector2f;
  end;

Code:

implementation

//
// TVector2f routines
//
function Vector2f(aX, aY: Single): TVector2f;
begin
  Result.x := aX;
  Result.y := aY;
end;

class operator TVector2f.Negative(const v: TVector2f): TVector2f;
begin
  Result.x := -v.x;
  Result.y := -v.y;
end;

class operator TVector2f.Add(const v1, v2: TVector2f): TVector2f;
begin
  Result.x := v1.x + v2.x;
  Result.y := v1.y + v2.y;
end;

class operator TVector2f.Subtract(const v1, v2: TVector2f): TVector2f;
begin
  Result.x := v1.x - v2.x;
  Result.y := v1.y - v2.y;
end;

class operator TVector2f.Multiply(const v: TVector2f; const s: Single): TVector2f;
begin
  Result.x := v.x * s;
  Result.y := v.y * s;
end;

procedure TVector2f.SetValue(const aX, aY: Single);
begin
  x := aX;
  y := aY;
end;

function TVector2f.Normalize: TVector2f;
var
  mag: Single;
begin
  mag := Len;
  if mag < 1 then mag := 1;
  x := x / mag;
  y := y / mag;

  Result.x := x;
  Result.y := y;
end;

function TVector2f.Len: Single;
begin
  Result := Sqrt(Sqr(x) + Sqr(y));
end;

function TVector2f.Dot(const v: TVector2f): Single;
begin
  Result := x * v.x + y * v.y;
end;

function TVector2f.Perp: TVector2f;
begin
  Result.SetValue(-y, x);
end;

I have tried, but it doesn't seem possible - the compiler is complaining

It says it does here, but I don't know if it is the version that comes with Lazarus 0.9.30:
http://wiki.freepascal.org/FPC_New_F..._record_syntax

cheers,
Paul