p_forward.mod 377 B

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  1. MODULE PFwd;
  2. VAR ExitCode : INTEGER;
  3. PROCEDURE Even(n : INTEGER) : BOOLEAN;
  4. FORWARD;
  5. PROCEDURE Odd(n : INTEGER) : BOOLEAN;
  6. BEGIN
  7. IF n = 0 THEN RETURN FALSE ELSE RETURN Even(n - 1) END
  8. END Odd;
  9. PROCEDURE Even(n : INTEGER) : BOOLEAN;
  10. BEGIN
  11. IF n = 0 THEN RETURN TRUE ELSE RETURN Odd(n - 1) END
  12. END Even;
  13. BEGIN
  14. IF Even(10) THEN ExitCode := 1 ELSE ExitCode := 0 END
  15. END PFwd.