On Thu, 23 Jul 2009 22:09:12 -0400, Sergey Gromov <snake.sc...@gmail.com>
wrote:
Thu, 23 Jul 2009 11:54:40 -0400, Steven Schveighoffer wrote:
On Wed, 22 Jul 2009 23:47:30 -0400, Sergey Gromov
<snake.sc...@gmail.com>
wrote:
Is there a way to declare and statically initialize some sort of
pointer
to method, and later call it for an actual object instance?
I don't know why the "non constant expression error" happens, but
constructing a delegate from function pointers is pretty simple:
It's my understanding that you cannot construct a delegate from a
function pointer because they use different calling conventions. Though
you show here that it *is* possible to construct a delegate from another
delegate you dissected earlier.
LOOKUP_TABLE[0] = Method("method1", &Component.method1);
LOOKUP_TABLE[1] = Method("method2", &Component.method2);
These two lines are weird. ``pragma(msg)`` shows that type of
``&method1`` is ``void function()`` while it must be ``void delegate()``
for a non-static member because of difference in calling convention.
Actually I think that taking an address of a non-static member in a
static context must be a compile time error.
It's because I'm taking the address of the function on the type, not on an
instance. It's not a delegate because there's no "this" pointer yet.
It makes sense to me anyways. A delegate is a normal function pointer
coupled with a hidden context parameter.
I think it should be possible to construct the table statically, since the
functions exist statically (without 'this' pointers). Either I can't find
the right syntax, or it is a bug.
-Steve
