Re: How to pass around access types to interfaces?

[Martin Krischik <krischik@users.sourceforge.net>]

Maciej Sobczak schrieb:
> On 26 Paź, 16:50, "Martin Krischik" <krisc...@users.sourceforge.net>
> wrote:
> 
>> But then: access to class wide is the kind of  
>> access which a C++ convert will uses without realy needing them. I should  
>> know, I am a C++ convert who made precisely that mistake.
> 
> It might depend on what you did in C++ before converting. ;-)
> Since most of the code does not need pointers anyway, the frequent
> idiom is to pass objects by reference (likely to the base class),
> something like:
> 
> void foo(const SomeClass & object);

Not the function call is the problem - the creation and storage of
objects is.

For example: now are you going to fill a vector<base_class&> with
objects? And how do you delete those objects again? This is where C++ lags.

In Ada we have Ada.Container.Indefinite_Vector which can hold Base'Class
objects. (Remember that is was me who requested the inclusion of
Ada.Container.Indefinite_Vector into the standard. It was also me who
created BC.Indefinite_Containers)

> I think that in the above context what is *really* dangerous and
> difficult to clean up is the C background, not C++. Unfortunately the
> former one prevails.

Well I did C before C++ and Modula-2 before that and Pascal before that.

Martin

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