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Order of type definitions

In Delphi types can be defined by other types, which aren't defined yet. In C++ a type only can be defined by another type, which is already defined. So the order of the Delphi type definitions has to be rearranged sometimes.

The following example is taken from the file "ShellApi.pas":

  PSHFileOpStructA = ^TSHFileOpStructA;
  PSHFileOpStructW = ^TSHFileOpStructW;
  PSHFileOpStruct = PSHFileOpStructA;
  {$EXTERNALSYM _SHFILEOPSTRUCTA}
  _SHFILEOPSTRUCTA = packed record
    Wnd: HWND;
    wFunc: UINT;
    pFrom: PAnsiChar;
    pTo: PAnsiChar;
    fFlags: FILEOP_FLAGS;
    fAnyOperationsAborted: BOOL;
    hNameMappings: Pointer;
    lpszProgressTitle: PAnsiChar; { only used if FOF_SIMPLEPROGRESS }
  end;
  {$EXTERNALSYM _SHFILEOPSTRUCTW}
  _SHFILEOPSTRUCTW = packed record
    Wnd: HWND;
    wFunc: UINT;
    pFrom: PWideChar;
    pTo: PWideChar;
    fFlags: FILEOP_FLAGS;
    fAnyOperationsAborted: BOOL;
    hNameMappings: Pointer;
    lpszProgressTitle: PWideChar; { only used if FOF_SIMPLEPROGRESS }
  end;
  {$EXTERNALSYM _SHFILEOPSTRUCT}
  _SHFILEOPSTRUCT = _SHFILEOPSTRUCTA;
  TSHFileOpStructA = _SHFILEOPSTRUCTA;
  TSHFileOpStructW = _SHFILEOPSTRUCTW;
  TSHFileOpStruct = TSHFileOpStructA;
  {$EXTERNALSYM SHFILEOPSTRUCTA}
  SHFILEOPSTRUCTA = _SHFILEOPSTRUCTA;
  {$EXTERNALSYM SHFILEOPSTRUCTW}
  SHFILEOPSTRUCTW = _SHFILEOPSTRUCTW;
  {$EXTERNALSYM SHFILEOPSTRUCT}
  SHFILEOPSTRUCT = SHFILEOPSTRUCTA;

This is translated to:

/*# waiting for definiens
typedef TSHFileOpStructA *PSHFileOpStructA;
*/ /*# waiting for definiens
typedef TSHFileOpStructW *PSHFileOpStructW;
*/ /*# waiting for definiens
typedef PSHFileOpStructA PSHFileOpStruct;
*/

/*$EXTERNALSYM _SHFILEOPSTRUCTA*/

#pragma pack(push, 1)
struct _SHFILEOPSTRUCTA {
  HWND Wnd;
  UINT wFunc;
  PAnsiChar pFrom;
  PAnsiChar pTo;
  FILEOP_FLAGS fFlags;
  BOOL fAnyOperationsAborted;
  void* hNameMappings;
  PAnsiChar lpszProgressTitle; /* only used if FOF_SIMPLEPROGRESS */
};

#pragma pack(pop);
  /*$EXTERNALSYM _SHFILEOPSTRUCTW*/

 #pragma pack(push, 1)
struct _SHFILEOPSTRUCTW {
  HWND Wnd;
  UINT wFunc;
  PWideChar pFrom;
  PWideChar pTo;
  FILEOP_FLAGS fFlags;
  BOOL fAnyOperationsAborted;
  void* hNameMappings;
  PWideChar lpszProgressTitle; /* only used if FOF_SIMPLEPROGRESS */
};

#pragma pack(pop);

/*$EXTERNALSYM _SHFILEOPSTRUCT*/

typedef _SHFILEOPSTRUCTA _SHFILEOPSTRUCT;
typedef TSHFileOpStructA *PSHFileOpStructA;
typedef PSHFileOpStructA PSHFileOpStruct;
typedef _SHFILEOPSTRUCTA TSHFileOpStructA;
typedef TSHFileOpStructW *PSHFileOpStructW;
typedef _SHFILEOPSTRUCTW TSHFileOpStructW;
typedef TSHFileOpStructA TSHFileOpStruct;
  /*$EXTERNALSYM SHFILEOPSTRUCTA*/
typedef _SHFILEOPSTRUCTA SHFILEOPSTRUCTA;
  /*$EXTERNALSYM SHFILEOPSTRUCTW*/
typedef _SHFILEOPSTRUCTW SHFILEOPSTRUCTW;
  /*$EXTERNALSYM SHFILEOPSTRUCT*/
typedef SHFILEOPSTRUCTA SHFILEOPSTRUCT;