Natools

------------------------------------------------------------------------------
-- Natools.String_Slices provide an object that represents a substring of a --
-- shared parent string.                                                    --
------------------------------------------------------------------------------

private with Natools.References;
private with Natools.Storage_Pools;

package Natools.String_Slices is
   pragma Preelaborate (String_Slices);

   -----------------------
   -- String range type --
   -----------------------

   function Duplicate (S : Slice) return Slice;
      --  Create a new parent string and a slice designating it.
      --  This does not copy parts of S parent string outside of S range.
      --  Semantically equivalent to (To_Slice (To_String (S))).

private

   type Access_In_Default_Pool is access Boolean;
      --  Access type only used to infer default storage pool

   package String_Refs is new References
     (String,
      Access_In_Default_Pool'Storage_Pool,
      Access_In_Default_Pool'Storage_Pool);
      Storage_Pools.Access_In_Default_Pool'Storage_Pool,
      Storage_Pools.Access_In_Default_Pool'Storage_Pool);

   type Slice is tagged record
      Bounds : String_Range := (1, 0);
      Ref : String_Refs.Reference;
   end record;

   Null_Slice : constant Slice := ((1, 0), Ref => <>);

end Natools.String_Slices;