Re: Ada-Singleton-Why does it work like this?

[Maciej Sobczak <see.my.homepage@gmail.com>]

On 26 Mar, 10:28, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:

> This highlights the point. "Singletonness" is not a property of the type
> used to implement it.

Depends. The type involves not only the set of possible states, but
also the set of possible operations. Is the creation as an operation
part of this set?
If creation belongs to the set of operations of some type, then
"singletonness" is obviously a property of the type.
If, on the other hand, creation does not belong to this set, then
indeed these concepts are orthogonal.

Can you defend the idea that creation does not belong to the type?

> So the pattern is all wrong.

Or not - maybe it is a way to express some property of the *type* that
cannot be expressed due to the limitations in the language?

--
Maciej Sobczak * www.msobczak.com * www.inspirel.com

Database Access Library for Ada: www.inspirel.com/soci-ada