Appendix E: Specification of the Package Ada.Calendar

This appendix, adapted from the Ada 95 Reference Manual, Section 9.6, gives the specifications for the package Ada.Calendar.

PACKAGE Ada.Calendar IS

  TYPE Time IS PRIVATE;

  SUBTYPE Year_Number  IS Integer  RANGE 1901..2099;
  SUBTYPE Month_Number IS Integer  RANGE 1..12;
  SUBTYPE Day_Number   IS Integer  RANGE 1..31;
  SUBTYPE Day_Duration IS Duration RANGE 0.0..86_400;

  FUNCTION Time_Of ( Year : Year_Number;
                     Month : Month_Number;
                     Day : Day_Number;
                     Seconds  : Day_Duration:=0.0) RETURN Time;

  FUNCTION Year  ( Date : Time)  RETURN Year_Number;
  FUNCTION Month ( Date : Time)  RETURN Month_Number;
  FUNCTION Day  ( Date : Time)   RETURN Day_Number;
  FUNCTION Seconds ( Date : Time) RETURN Day_Duration;

  PROCEDURE Split ( Date    : IN  Time;
                    Year     : OUT Year_Number;
                    Month    : OUT Month_Number;
                    Day      : OUT Day_Number;
                    Seconds  : OUT Day_Duration);

  FUNCTION Clock RETURN Time;

  FUNCTION "<"  ( Left, Right : Time)      RETURN Boolean;
  FUNCTION "<=" ( Left, Right : Time)      RETURN Boolean;
  FUNCTION ">"  ( Left, Right : Time)      RETURN Boolean;
  FUNCTION ">=" ( Left, Right : Time)      RETURN Boolean;

  FUNCTION "+" ( Left : Time;     Right : Duration)  RETURN Time;
  FUNCTION "+" ( Left : Duration; Right : Time)      RETURN Time;
  FUNCTION "-" ( Left : Time;     Right : Duration)  RETURN Time;
  FUNCTION "-" ( Left : Time;     Right : Time)      RETURN Duration;
  Time_Error : EXCEPTION;

PRIVATE

  -- not specified by the language 

END Ada.Calendar;