Re: _Type vs no _Type

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

Le Sat, 06 Nov 2010 22:20:19 +0100, Shark8 <onewingedshark@gmail.com> a  
écrit:
> Being relatively new to Ada, I didn't know about "use type" when I ran
> into the problem and used dot-qualification instead of the [otherwise-
> needed] "use".

In few words, this is a useful feature to Use all operations of a type  
without requiring to Use the whole package where it is defined and without  
(like this would be if you wanted to avoid to Use the whole package) to  
import these operations via renames clause.

if package A defines a type and some operations, if you want to invok  
these operation with using a prefix notation of many renames clause, the  
you can do a “use type”.

This is especially useful with predefined operators like “+”, “-”, when  
this way you can get ride of all of these “My_Package."+"(Left =>  
Expression_1, Right => Expression_2)”

For more details, see (Ada 2005):
http://www.adaic.org/standards/05rm/html/RM-8-4.html

But as this did not solved everything, ex. you still have to use a prefix  
to refer to enumeration items as an example, the “use type” has been  
extended in Ada 2012, with a “use all type”, which import every thing of a  
type, no more restricted to its operations.

For more details, see (Ada 2012):
http://www.ada-auth.org/standards/12rm/html/RM-8-4.html

And also if you are inquisitive:
http://www.ada-auth.org/cgi-bin/cvsweb.cgi/ai05s/ai05-0150-1.txt?rev=1.8
> There have been complaints that a use type clause does not make
> enough things visible (e.g. enumeration literals, classwide operations
> for tagged types), whereas a use_package_clause makes too much visible.
> Something in between is wanted.

By the way: do someone know why the Ada LRM 2012 has moved from AdaIC to  
Ada-Auth ?


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