Mixing operators and dot notation

["Alejandro R. Mosteo" <alejandro@mosteo.com>]

Hello all,

I'm trying to abuse Ada syntax for nefarious purposes and have arrived 
at something that looks inconsistent to me, but I fail to see if it is 
expected behavior or a bug. This is a self-contained example which is below.

The gist is to have an operator that returns a class-wide type in order 
to use dot notation on it. The problem is in the last statement. Should 
it work just like the function version?:

procedure Cla is

    generic
    package Nested is
          type Object is tagged null record;
	 procedure Method (O : Object) is null;
    end Nested;

    package Nest is new Nested;

    function Op (X, Y : Integer) return Nest.Object'Class is
       pragma Unreferenced (X, Y);
    begin
       return Nest.Object'(null record);
    end Op;

    function "&" (X, Y : Integer) return Nest.Object'Class renames Op;

    N : Nest.Object'Class := Op (1, 2);
    M : Nest.Object'Class := 1 & 2; -- Both work

begin
    N.Method;
    M.Method; -- Of course both work

    Op (1, 2).Method;  --  Fine

    --  (1 & 2).Method;  --  Error: statement expected
end Cla;