Hi again,
   I would like to have your feedbacks about this.

Description:
   Ability of declaring 'anonymous' array members within
classes/structures.

Example:
   struct X
   {
      int a;
      int[20];  // anonymous member
      int b;
      char[5];  // anonymous member
   };

Motivation:
   This can be useful for:
      - std. way of providing 'holes' inside structures
      - readability: clearly saying "I want a padding space here",
don't care about the name you use  (sometimes I saw it as '_padding',
as 'dummy', as 'blanco', as 'blank',...)
      - forcing a structure of having a fixed length, and ensuring you
don't overgo that size when adding members in the member (see below)
      - [definition: anonymous members are not formal members; they
are not initialized nor accessible]. Don't need to initialize them in
the { } initialization as far as they are not accessable
        Example using structure X defined above:
            struct X x = { 1, 2 };
        member 'a' initialized with '1' and member 'b' initialized
with '2'.

Sample application:
   -> Forcing a structure to have a fixed length. (Additional rule
required)
   Suppose I want to declare a structure Message, of a fixed length of
128 bytes. This structure could have more members in the future (as
the system maintenance continues), but must not exceed this length.

   struct Message
   {
     int member1;
     double member2;
     char description[50];
   };

   template <class Content, size_t fixedSize> struct FixedLength :
Content
   {
      char[ fixedSize - sizeof(Content)];
   };

   void usage(void)
   {
     FixedLength<Message,128> msg = { 1, 3.14, "this is a message" };
   }

   The additional rule required (and also proposed) is that:
structures/classes with single and public inheritance can have '{  }'
initialization iif they have no own members.
   This is because (I don't have the standard here, I don't recall how
are they named) derived structs cannot be initialized with '{ }', but
this rule would be an exception: when they have no members and the
inheritance is public and single (according to the definition above,
FixedLength has no own members as far as the anonymous padding is not
a member).

   Open ideas: maybe you can suggest a better way of doing this
without inheritance (perhaps something with anonymous structures?).
Listening comments.

Compatibility:
  This proposal is an invalid syntax in current C++, therefore
provides full compatibility.

Thanks!
   Daniel.

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