Re: generic package

[Stephen Leake <Stephe.Leake@nasa.gov>]

"Ratson Janiv" <janiv@013.net.il> writes:

> generic
>     type Language is array (Positive range<>) of Character;
>     type States is array (Positive range <>) of Integer;
> 
>     package Automat_Producer is
> 
>     type StatesFunctions is array(Character,Integer) of Integer;
> 
>     procedure Init(Q0:Integer);
>     procedure Change_State(C:Character);
>     function Is_Final_State return Boolean;
> 
> private
> 
>     Statesarr: Statesfunctions;
>     Currentstate : Integer;
>     FinalStates : States;
> 
> end Automat_Producer;
> 
> I have few Questions:
> 
> How and when do I set the sizes of the generic types arrays?
> The compiler need to know the size of the FinalStates:States member, I will
> know it only during run-time, How do I do it ?

The general answer to this question is to use a local declare block.
Something like:

procedure foo
is
   size : Integer;
begin
   get (Size);

   declare
      subtype Language_Range is Positive range 1 .. Size;
      type Language is array (language_range) of character;
    
      package Producer is new Automat_Producer (Language ...);
   begin
      ...
   end;
end;

-- 
-- Stephe