Re: generics in Ada 83

[Jean-Pierre Rosen <rosen@adalog.fr>]

Jeffrey Carter a �crit :
> Defaults are defined for subprograms by inserting "is Name" or "is <>" 
> before the semicolon (;):
> 
>    with procedure Y (Z : in X) is A;
> 
> or
> 
>    with procedure Y (Z : in X) is <>;
> 
> You can't use the former, since it requires a procedure A, visible at 
> the point of the generic, that matches Y. Since you don't know what X is 
> at the point of the generic, you can't have such a procedure.
> 
Let me add something which is maybe not obvious to the OP:
In Ada, the legality of a generic is checked on the generic, not on the 
instantiation. This is a main difference with templates.

The benefit is that if a generic compiles, and the instantiation 
provides parameters that match the contract (of the generic formals), 
then the instantion is *always* OK.

-- 
---------------------------------------------------------
            J-P. Rosen (rosen@adalog.fr)
Visit Adalog's web site at http://www.adalog.fr