Re: Convention for naming of packages

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

On Tue, 14 Feb 2012 10:08:37 +0100, Yannick Duchêne (Hibou57) wrote:

> Le Mon, 13 Feb 2012 22:02:17 +0100, Dmitry A. Kazakov  
> <mailbox@dmitry-kazakov.de> a écrit:

>>> About package holding singleton really holding singleton, like say a Log
>>> package which would create a singleton file "Log.File" objct, I believe
>>> that's not good for re‑usability (ex. what about multiple task?). Better
>>> provide a type with a constructor,
>>
>> Constructor = constructor or constructor = constructing function? The
>> latter is bad design.
> I never get into trouble with this. If I am likely to get into troubles  
> with it, I would like to know before it happens and have a chance to  
> prevent it before, obviously. On the mean time, I'm not a big tagged type  
> user, and feel to understand your objections to it, mainly applies to  
> tagged types hierarchies.

You may have a constructor for a singleton type because constructor cannot
be called explicitly and you cannot get rid of the constructor anyway. The
constructor is generated by the compiler (except for misuses of the pragma
Import (Ada, etc).

You shall never provide a constructing function (=factory) for singleton
types. A factory can be used several times, which you, as a package
provider, cannot control.

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