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Subject: Address of member in class scope
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Xref: g2news1.google.com comp.std.c++:8085

Can someone tell me why the following code won't compile? I am taking
the address of a class member within the class's declaration. This
works for a pointer to member function, but fails for a pointer to
data member. Is my compiler at fault? Or does the standard explicitly
forbid this?

struct Example
{
  // Template that takes a pointer to member function
  template<void (Example::*member)(int)>
    struct Command
    {
      void Set(Example& example, int value) { (example.*member)
(value); }
    };

  // Template that takes a pointer to data member
  template<int Example::*member>
    struct Property
    {
      void Set(Example& example, int value) { (example.*member) =
value; }
    };

  int value_;

  Example() : value_(0) {}

  int Get() const { return value_; }
  void Set(int value) { value_ = value; }

  // Can take an address of member function
  Command<&Example::Set> Setter;        // compiles...

  // Can NOT take an address of data member
  //Property<&Example::value_> Value;   // !!! WILL NOT COMPILE !!!

  // Can take an address of data member inside a function
  void SetValue(int value)
  {
    Property<&Example::value_> Value;   // compiles...
    Value.Set(*this, value);
  }
};

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