[sv-ec] E-mail Vote (part 2) - mantis 1500

<resend - majordomo gagged on it the first time>

1500  ___ Yes   _X_ No

I think I know what you are getting at, but the distinction between a "forward
typedef" and an "empty typedef" needs to be made more clear before we
can approve this mantis item. The biggest question appears to be; what is a
forward typedef?

a. "Forward typedef" versus "empty typedef"

   Both of these terms are used in sub-clause 4.9 and 7.24.

   The following text is in sub-clause 4.9. I assume that you aren't suggesting
   that this example is now illegal. The example shows two typedefs for the
   same user-defined type (i.e. foo). The text doesn't mention anything about
   a requirement for two typedefs for an "empty typedef" and there is only
   one example.

      A type can be used before it is defined, provided it is first identified
      as a type by an empty typedef:

         typedef foo;    // is this a forward typedef or just an empty typedef?
         foo f = 1;
         typedef int foo;  // a second typedef for foo

    Mantis 1500 wants to make the following illegal?

         typedef foo;   // I assume this is what you mean by forward typedef
         foo f = 1;
         int foo;       // error - missing typedef - forward typedef only
                        // allowed for classes

    Later in sub-clause 4.9 there is the following text. Here it refers to
    the example in 7.24 as using an "empty typedef".

       While an empty user-defined type declaration is useful for coupled
       definitions of classes as shown in 7.24, it cannot be used for...

    In sub-clause 7.24 the following example is shown:

         typedef class C2;     // C2 is declared to be of type class
         class C1;
            C2 c;
         endclass
         class C2;
            C1 c;
         endclass

    The text in sub-clause 7.24 goes on to say that this example is the
    same as this. Note that this version uses an empty typedef:

         typedef C2;   // both an empty typedef and a forward typedef?
         class C1;
            C2 c;
         endclass
         class C2;     // no typedef required
            C1 c;
         endclass

b. Friendly amendment

   The text that you are quoting from sub-clause 4.9 contains the following
   text.

   From:
      ... it cannot be used ...
   To:
      ... it shall not be used ...

c. Friendly amendment

   From:
      ... to declare an instance of a class ...
   To:
      ... to declare a handle to an instance of a class ...



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