On Monday, 14 May 2012 at 12:22:30 UTC, Steven Schveighoffer
wrote:
On Mon, 14 May 2012 02:35:16 -0400, Jakob Ovrum
<[email protected]> wrote:
How about logically constant opEquals, toString etc?
Currently, this is perfectly possible by just *not using
const*. Logical constancy goes beyond memoization.
This means you cannot compare two const objects.
Yes, but using const for these objects makes no sense because
they all require temporary mutation (the Lua stack) to do
anything meaningful. This includes opEquals and toString. Thus
the option should be there not to use const.
The issue is, non-const opEquals makes sense on some objects,
and const opEquals makes sense on others. However, you must
make them all come together in Object.opEquals.
I think we already have the hooks to properly compare objects
without requiring Object.opEquals.
Right now, when two objects are compared, the compiler calls
object.opEquals (that's little o for object, meaning the module
function *not* the class method).
So why can't object.opEquals be a template that decides whether
to use Object.opEquals (which IMO *must be* const) or a derived
version? I don't think it's that much of a stretch (not sure
if we need a compiler fix for this).
-Steve
Right, I think this is the way to go. We have to accommodate both
kind of object.
