------------------------------------------------------------------------------
--                                                                          --
--                         GNAT RUN-TIME COMPONENTS                         --
--                                                                          --
--            A D A . N U M E R I C S . F L O A T _ R A N D O M             --
--                                                                          --
--                                 S p e c                                  --
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--          Copyright (C) 1992-2020, Free Software Foundation, Inc.         --
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-- This specification is derived from the Ada Reference Manual for use with --
-- GNAT. The copyright notice above, and the license provisions that follow --
-- apply solely to the  contents of the part following the private keyword. --
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-- GNAT is free software;  you can  redistribute it  and/or modify it under --
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-- <http://www.gnu.org/licenses/>.                                          --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
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--                                                                          --
------------------------------------------------------------------------------

--  Note: the implementation used in this package is a version of the
--  Mersenne Twister. See s-rannum.adb for details and references.

with System.Random_Numbers;

package Ada.Numerics.Float_Random with
  SPARK_Mode => Off
is

   --  Basic facilities

   type Generator is limited private;

   subtype Uniformly_Distributed is Float range 0.0 .. 1.0;

   function Random (Gen : Generator) return Uniformly_Distributed;

   procedure Reset (Gen : Generator);
   procedure Reset (Gen : Generator; Initiator : Integer);

   --  Advanced facilities

   type State is private;

   procedure Save  (Gen : Generator; To_State   : out State);
   procedure Reset (Gen : Generator; From_State : State);

   Max_Image_Width : constant := System.Random_Numbers.Max_Image_Width;

   function Image (Of_State    : State)  return String;
   function Value (Coded_State : String) return State;

private

   type Generator is new System.Random_Numbers.Generator;

   type State is new System.Random_Numbers.State;

end Ada.Numerics.Float_Random;
