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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: Limited initialization for non-limited types
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Date: Wed, 26 Mar 2008 16:08:01 +0100
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Date: 2008-03-26T16:08:01+01:00
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On Wed, 26 Mar 2008 06:26:42 -0700 (PDT), Eric Hughes wrote:

> Is there any way of getting in-place initialization for non-limited
> objects?

[...]

It is both simpler and more complex. What is IMO needed:

1. Extensible operations. (That is when a primitive operation has
non-overridable parts, like constructors, destructors, assignments,
aggregates usually do.)

2. Assignment (a part of) as a doubly dispatching primitive operation. (In
order to have access to LHS and RHS, which is one problem in your example)

3. Constructor (a part of) as a primitive operation. (Again, to access LHS,
which is another problem you have)

4. Multi-stage construction/assignment model. (In order to handle
discriminants before allocation, allocation before components
initialization and components before assignment completion)

----------
P.S. Supertypes, classes for all types, multiple inheritance. These will
give you a way to hang your tracing stuff on any existing type rather than
deriving them from a common base.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de