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-- This file is part of 'Finite Field Arithmetic', aka 'FFA'.               --
--                                                                          --
-- (C) 2017 Stanislav Datskovskiy ( www.loper-os.org )                      --
-- http://wot.deedbot.org/17215D118B7239507FAFED98B98228A001ABFFC7.html     --
--                                                                          --
-- You do not have, nor can you ever acquire the right to use, copy or      --
-- distribute this software ; Should you use this software for any purpose, --
-- or copy and distribute it to anyone or in any manner, you are breaking   --
-- the laws of whatever soi-disant jurisdiction, and you promise to         --
-- continue doing so for the indefinite future. In any case, please         --
-- always : read and understand any software ; verify any PGP signatures    --
-- that you use - for any purpose.                                          --
--                                                                          --
-- See also http://trilema.com/2015/a-new-software-licensing-paradigm .     --
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with Word_Ops; use Word_Ops;

-- Elementary Predicates on Words:
package body W_Pred is
   
   -- Return 1 if N is equal to 0; otherwise return 0.
   function W_ZeroP(N : in Word) return WBool is
   begin
      return W_Borrow(N, 1, N - 1);
   end W_ZeroP;
   pragma Inline_Always(W_ZeroP);
   
   
   -- Return 1 if N is unequal to 0; otherwise return 0.
   function W_NZeroP(N : in Word) return WBool is
   begin
      return 1 xor W_ZeroP(N);
   end W_NZeroP;
   pragma Inline_Always(W_NZeroP);
   
   
   -- Return WBool-complement of N.
   function W_Not(N : in WBool) return WBool is
   begin
      return 1 xor N;
   end W_Not;
   pragma Inline_Always(W_Not);
   
   
   -- Return 1 if N is odd; otherwise return 0.
   function W_OddP(N : in Word) return WBool is
   begin
      return 1 and N;
   end W_OddP;
   pragma Inline_Always(W_OddP);
   
   
   -- Return 1 if A is equal to B ; otherwise return 0.
   function W_EqP(A : in Word; B : in Word) return WBool is
   begin
      return W_ZeroP(A xor B);
   end W_EqP;
   pragma Inline_Always(W_EqP);
   
end W_Pred;