Re: Task safe containers? Help needed.

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

On 2017-10-08 17:10, reinert wrote:

> About your first option: Putting the containers in a protected
> object  makes the container functions "private" and not directly available
> outside the protected object. Right?

Which is good, since they are unsafe.

> But your other options also somehow complicates :-)

Not at all.

> A compromise seems to be necessary :-)

There is no compromise, each method has its use.

> Maybe the first option anyway
> facilitates cleanest code?

No. The cleanest code would be per delegation. Ada has none. Then there 
are issues with interface functions while most relevant synchronization 
mechanisms considered mutating. The Rosen's trick is used to work that 
around. A problem for monitor (#2.b) is to have an unconstrained result, 
since task entries cannot return such.

> There must be a reason for the invention of
> protected types.

The reason was to add an OO view on synchronization as a complement to 
the procedural view tasks offer.

The implementation provided by protected objects was chosen to be most 
efficient, powerful, safe, verifiable and universal. Which comes with 
certain limitations.

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