Re: Protected Type compiler complaint

[NiGHTS <nights@unku.us>]

On Monday, July 7, 2014 3:55:24 AM UTC-4, Simon Wright wrote:

> > When I compile it complains that "protected declaration cannot be used
> 
> > as compilation unit" on line 1 of test.ads. So I remove those files
> 
> > from the project source files options menu. Then when I compile again
> 
> > it complains about "test.ads not found" on line 3 of main.adb.
> 
> 
> 
> A protected declaration cannot be used as a compilation unit; it has to
> 
> be declared within one.
> 
> 
> 
> > Here is a summarized view of what my test.ads looks like:
> 
> >
> 
> >    protected type Test is procedure DoSomething; end Test;
> 
> 
> 
>    package Test is
> 
>       protected type P is
> 
>         procedure Do_Something;
> 
>       end P;
> 
>    end Test;
> 
> 
> 
> > And here is a summarized view of what my main.adb looks like:
> 
> >
> 
> >    with Test; use Test;
> 
> >
> 
> >    procedure main is begin Test.DoSomething; end;
> 
> 
> 
> You made Test a protected *type* (and I've suggested Test.P), so you
> 
> need to declare a protected *object* of that type.
> 
> 
> 
>    with Test;
> 
>    procedure Main is
> 
>       O : Test.P;
> 
>    begin
> 
>       O.Do_Something;
> 
>    end Main;

Thank you for your help. This makes sense. 

A question about the variables in the Test.P type you introduced. I would like to make available to other spawned tasks these protected variables, so essentially Test.P needs to be a global of some kind with static data in the currently running process. I heard much about not creating global variables for good Ada coding practice, so how is this protected package variables expected to be usable by these spawned tasks? 

NOTE: The task code may not be directly associated to the main package as I expect to create task utility packages shared by multiple applications.


Thank you again for your help.