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Subject: Re: Pointer to instance of indefinite array?
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Date: Wed, 13 Aug 2014 11:58:37 -0600
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Date: 2014-08-13T11:58:37-06:00
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On 13-Aug-14 10:06, NiGHTS wrote:
> Of course this will be via an entry to a protected object but
> those details aside how can I construct a constrained array
> of indefinite arrays?

For that you *do* need accesses, this is because the compiler needs to 
know the size of the elements. Of course this implementation detail can 
be hidden away from clients:
Package Test_UCA is

     Type Positive_Array is Array (Positive Range <>) of Positive;
     Type Array_Array(Len : Positive) is Private;

     -- Obj's Entries should be used as follows:
     -- O.Test( P ); -- Saves P into J.
     -- ...
     -- O.Result_Length( Temp ); -- Gets the length of J.
     -- declare
     --   New_Array : Positive_Array(1..Temp);
     -- begin
     --    O.Result( New_Array ); -- Copies J into New_Array & clears J.
     --  --... (Whatever processing you need.)
     -- end;
   Protected type Obj(Len : Positive) is
     Entry Test		( P	: Positive_Array );
     Entry Result_Length	( Len	: out Positive );
     Entry Result	( R	: out Positive_Array );
   Private
     J : access Positive_Array;
     K : Array_Array(Len);
   End Obj;

Private
   Type Internal_Array_Array is Array (Positive Range <>) of not null 
access Positive_Array;
   Type Array_Array(Len : Positive) is record
     Data :  Internal_Array_Array(1..Len);
   end record;


   Default : Constant Internal_Array_Array:= ( 1..0 => New 
Positive_Array'(1,1) );
End Test_UCA;


Package Body Test_UCA is
     Protected Body Obj is

         Entry Test		( P	: Positive_Array ) when True is
         Begin
             J:= new Positive_Array'(P);
         End Test;

         Entry Result_Length	( Len	: out Positive ) when J /= null is
         Begin
             Len:= J'Length;
         End Result_Length;

         Entry Result	( R	: out Positive_Array ) when J /= null is
         Begin
             R:= J.All;
             J:= Null;
         End Result;

     End Obj;
End Test_UCA;