sizeof(static array[])

[staticVoid]

hi, I have a static array, as a static class member whichz definition looks a bit like:

//.h

class A
{
public:
   static struct _Foo { int x, y, z; } Foo[];
};


.cpp

A::_Foo A::Foo[] = 
{
   { 1, 2, 3 },
   { 4, 5, 6 },
   { 7, 8, 9 }
};

when I ask the compiler for the sizeof(A::Foo) it says its an invalid use of the sizeof directive, this seems a bit strange to me, when you initialize Foo, there will only be a fixed amount of _Foo structs in the array, so why can't the compiler give me this value?