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natools-static_maps-s_expressions-conditionals-strings-p.adb at [90bba135f9]
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File generated/natools-static_maps-s_expressions-conditionals-strings-p.adb artifact 4afcbe25fa part of check-in 90bba135f9


with Interfaces; use Interfaces;

package body Natools.Static_Maps.S_Expressions.Conditionals.Strings.P is

   P : constant array (0 .. 2) of Natural :=
     (2, 11, 13);

   T1 : constant array (0 .. 2) of Unsigned_8 :=
     (9, 9, 0);

   T2 : constant array (0 .. 2) of Unsigned_8 :=
     (6, 4, 5);

   G : constant array (0 .. 16) of Unsigned_8 :=
     (0, 5, 0, 1, 0, 6, 0, 0, 7, 0, 0, 0, 0, 1, 1, 0, 3);

   function Hash (S : String) return Natural is
      F : constant Natural := S'First - 1;
      L : constant Natural := S'Length;
      F1, F2 : Natural := 0;
      J : Natural;
   begin
      for K in P'Range loop
         exit when L < P (K);
         J  := Character'Pos (S (P (K) + F));
         F1 := (F1 + Natural (T1 (K)) * J) mod 17;
         F2 := (F2 + Natural (T2 (K)) * J) mod 17;
      end loop;
      return (Natural (G (F1)) + Natural (G (F2))) mod 8;
   end Hash;

end Natools.Static_Maps.S_Expressions.Conditionals.Strings.P;