static arrays becoming value types

[Walter Bright]

Currently, static arrays are (as in C) half-value types and 
half-reference types. This tends to cause a series of weird problems and 
special cases in the language semantics, such as functions not being 
able to return static arrays, and out parameters not being possible to 
be static arrays.

Andrei and I agonized over this for some time, and eventually came to 
the conclusion that static arrays should become value types. I.e.,

   T[3]

should behave much as if it were:

   struct ??
   {
      T[3];
   }

Then it can be returned from a function. In particular,

   void foo(T[3] a)

is currently done (as in C) by passing a pointer to the array, and then 
with a bit of compiler magic 'a' is rewritten as (*a)[3]. Making this 
change would mean that the entire array would be pushed onto the 
parameter stack, i.e. a copy of the array, rather than a reference to it.

Making this change would clean up the internal behavior of types. 
They'll be more orthogonal and consistent, and templates will work better.

The previous behavior for function parameters can be retained by making 
it a ref parameter:

    void foo(ref T[3] a)