Re: smart pointer dangerous (no -> operator)

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Fri, 16 Jan 2009 12:42:17 +0100, Georg Bauhaus wrote:

> Dmitry A. Kazakov schrieb:
>> On Fri, 16 Jan 2009 11:04:57 +0100, Oliver Kowalke wrote:
>> 
>>> Ada doesn't support the dereference operator -> as C++.
>>>
>>> So Ada provides only two ways to access the managed object?
> 
>> Two major problems are:
>> 
>> 1. Lack of delegation in order to automate generation of wrappers like Foo.
>> 2. Lack of MI, because one base type is required and used further extension
>> of the target type becomes practically impossible.
> 
> Frequently overlooked, I think, Ada has nested scopes, useful
> in many ways here.

This is an unrelated issue. Referential semantics is not necessarily about
object life time management. Surely a better support provided by Ada for
stack allocated objects eliminates some cases of smart pointers typical in
C++. But the problem of referential objects exists independently on that.

Yes, if Ada had abstract access types, the positions 1 and 2 would be not
needed in this concrete case, because built-in access types in Ada already
"delegate" to the target, when operation "." is used. But Ada lacks
abstract access types either.

See last month's discussion: "Run-time accessibility checks (was:
Construction initialization problem)"

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