------------------------------------------------------------------------------
--                                                                          --
--                         GNAT RUN-TIME COMPONENTS                         --
--                                                                          --
--                        S Y S T E M . E X P O N U                         --
--                                                                          --
--                                 S p e c                                  --
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--          Copyright (C) 1992-2022, Free Software Foundation, Inc.         --
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-- GNAT is free software;  you can  redistribute it  and/or modify it under --
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-- GNAT was originally developed  by the GNAT team at  New York University. --
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--                                                                          --
------------------------------------------------------------------------------

--  Modular integer exponentiation

--  Preconditions in this unit are meant for analysis only, not for run-time
--  checking, so that the expected exceptions are raised. This is enforced
--  by setting the corresponding assertion policy to Ignore. Postconditions
--  and contract cases should not be executed at runtime as well, in order
--  not to slow down the execution of these functions.

pragma Assertion_Policy (Pre            => Ignore,
                         Post           => Ignore,
                         Contract_Cases => Ignore,
                         Ghost          => Ignore);

generic

   type Int is mod <>;

function System.Exponu (Left : Int; Right : Natural) return Int
with
  SPARK_Mode,
  Post => System.Exponu'Result = Left ** Right;