Re: Convention for naming of packages

["Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr>]

Le Mon, 13 Feb 2012 16:11:49 +0100, Dmitry A. Kazakov  
<mailbox@dmitry-kazakov.de> a écrit:

> On Mon, 13 Feb 2012 15:20:30 +0100, Yannick Duchêne (Hibou57) wrote:
>
>> A package defines either, a domain, some relationships, a process, an
>> object type (at least to me), possibly some other high level concepts  
>> too.
>> Let talk about a package defining an object, to keep one single example.
>
> Don't think that singletone is a good idea. In any case, its use is quite
> marginal in Ada, if any.
>
>> An object type has methods for creation;
>
> A singletone may not have such method. Semantically, you should not be  
> able
> create a singletone explicitly.

Seems my wording was unclear. I meant a package describing, specifying (by  
Package, I mean the interface, not the body) something. A package is not  
an instance of the object if discribes (when its purpose is to describe an  
object), it defines it. I you want to say it by mean of singleton, so I  
would see only one: an instance of a kind of meta‑class. The only  
instanciation provided by a package, is its body (when applicable), not  
the object it describes.


>> The example with Element_Type which may be a Symbol_Type in some  
>> context,
>> explains why I said this may be compared to genericity.
>>
>> Static genericity seems adopted without too much objections in the  
>> “crowd”
>> of Ada application authors.
>
> Static polymorphism is OK so long the semantics of overloaded entities is
> same. The semantics of Element_Type is? Element + type? That looks far  
> too thin.
The semantic may be thin, if the semantic is thin, then its specification  
cannot be said too much thin for the sole reason it's thin.

Element_Type would be Element + Type, as you say, and also what appears as  
the second parameter of an Add method. Its presence as the second  
parameter of Add defines what Element_Type is (not just its name “Element”  
and its Type status in the Ada source text).

This may be thin, while still enough and all if nothing more is expected.  
The name “Element” is an hint for the reader, a reminder of the main  
abstraction which applies to it.

-- 
“Syntactic sugar causes cancer of the semi-colons.” [1]
“Structured Programming supports the law of the excluded muddle.” [1]
[1]: Epigrams on Programming — Alan J. — P. Yale University