_FAR_NO_NAMELESS_UNIONS

Far Manager

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_FAR_NO_NAMELESS_UNIONS

The macro _FAR_NO_NAMELESS_UNIONS controls whether the FarDialogItem structure uses anonymous unions. Anonymous unions are a language feature that is allowed by the C++ standard but not supported in ANSI C.

If the macro _FAR_NO_NAMELESS_UNIONS is not defined, the FarDialogItem structure will be compatible with FAR Manager versions prior to FAR 1.70 beta 3 (inclusive). So the FarDialogItem structure will have the following form:

struct FarDialogItem
{
  ...
  union {
    int Selected;
    char *History;
    char *Mask;
    struct FarList *ListItems;
    CHAR_INFO *VBuf;
  };
  ...
  union {
    char Data[512];

    struct {
      DWORD PtrFlags;
      int   PtrLength;
      char *PtrData;
      char  PtrTail[1];
    } Ptr;
  };
};

So to access the Data member of the FarDialogItem structure it will be suficient to write Data, and to access the Selected member - Selected.

If the macro _FAR_NO_NAMELESS_UNIONS is defined, the structure will use named unions. Then it will be compatible with ANSI C compilers, but will not be source-level compatible with plugins written for FAR 1.65. The structure will have the following form:

struct FarDialogItem
{
  ...
  union {
    int Selected;
    char *History;
    char *Mask;
    struct FarList *ListItems;
    CHAR_INFO *VBuf;
  } Param;
  ...
  union {
    char Data[512];

    struct {
      DWORD PtrFlags;
      int   PtrLength;
      char *PtrData;
      char  PtrTail[1];
    } Ptr;
  } Data;
};

In this case to access the Data member of the structure you will have to write Data.Data, and to access the Selected member - Param.Selected.

The macro must be defined before the #include "plugin.hpp" directive:

#define _FAR_NO_NAMELESS_UNIONS
#include "plugin.hpp"

Attention!

In FAR 1.70 beta 4, the default variant is compatible with old plugins (_FAR_NO_NAMELESS_UNIONS is not defined). However, in FAR 1.70 release the new default will be _FAR_NO_NAMELESS_UNIONS. So if you want your plugins to be source-level compatible with FAR 1.70 release, you can right now define the _FAR_NO_NAMELESS_UNIONS macro and modify the source code of your plugins accordingly.