    indexing
    	description: "Absolute temporal values composed of a date and a time"
    	legal: "See notice at end of class."
    	status: "See notice at end of class."
    	date: "$Date: 2006-01-22 18:25:44 -0800 (Sun, 22 Jan 2006) $"
    	revision: "$Revision: 56675 $"
    	access: date, time

    class interface
    	DATE_TIME

    create
    	make (y, mo, d, h, mi, s: INTEGER_32)
    			-- Set year, month day to `y', `mo', `d'.
    			-- Set hour, minute, second to `h', `mi', `s'.
    		require
    			correct_date_time: is_correct_date_time (y, mo, d, h, mi, s, False)
    		ensure
    			year_set: year = y
    			month_set: month = mo
    			day_set: day = d
    			hour_set: hour = h
    			minute_set: minute = mi
    			second_set: second = s

    	make_fine (y, mo, d, h, mi: INTEGER_32; s: REAL_64)
    			-- Set year, month day to `y', `mo', `d'.
    			-- Set hour, minute, second to `h', `m', `s'.
    		require
    			correct_date_time: is_correct_date_time (y, mo, d, h, mi, s, False)
    		ensure
    			year_set: year = y
    			month_set: month = mo
    			day_set: day = d
    			hour_set: hour = h
    			minute_set: minute = mi
    			second_set: fine_second = s

    	make_by_date_time (d: DATE; t: TIME)
    			-- Set date to `d' and time to `t'
    		require
    			d_exists: d /= Void
    			t_exists: t /= Void
    		ensure
    			date_set: date = d
    			time_set: time = t

    	make_by_date (d: DATE)
    			-- Set date to `d' and time to origin of time.
    		require
    			d_exists: d /= Void
    		ensure
    			date_set: date = d
    			time_set: time.is_equal (time.origin)

    	make_now
    			-- Get the date and the time from the system.

    	make_now_utc
    			-- Get the date and the time from the system.

    	make_from_string (s: STRING_8; code: STRING_8)
    			-- Initialize from a "standard" string of form
    			-- `code'.
    			-- (For 2-digit year specifications, the current century is used as
    			-- base century.)
    		require
    			s_exists: s /= Void
    			c_exists: code /= Void
    			date_time_valid: date_time_valid (s, code)

    	make_from_string_with_base (s: STRING_8; code: STRING_8; base: INTEGER_32)
    			-- Initialize from a "standard" string of form
    			-- `code' with base century `base'.
    		require
    			s_exists: s /= Void
    			c_exists: code /= Void
    			base_valid: base > 0 and (base \\ 100 = 0)
    			date_time_valid: date_time_valid_with_base (s, code, base)

    	make_from_string_default (s: STRING_8)
    			-- Initialize from a "standard" string of form
    			-- default_format_string.
    			-- (For 2-digit year specifications, the current century is used as
    			-- base century.)
    		require
    			s_exists: s /= Void
    			date_time_valid: date_time_valid (s, default_format_string)

    	make_from_string_default_with_base (s: STRING_8; base: INTEGER_32)
    			-- Initialize from a "standard" string of form
    			-- default_format_string with base century `base'.
    		require
    			s_exists: s /= Void
    			base_valid: base > 0 and (base \\ 100 = 0)
    			date_time_valid: date_time_valid_with_base (s, default_format_string, base)

    feature -- Access

    	date: DATE
    			-- Date of the current object

    	date_default_format_string: STRING_8
    			-- Default output format for dates
    			-- (from DATE_CONSTANTS)

    	date_duration: DATE_DURATION
    			-- Definite duration between origin of date and current date

    	date_time_tools: DATE_TIME_TOOLS
    			-- Tools for outputting dates and times in different formats
    			-- (from TIME_UTILITY)

    	day: INTEGER_32
    			-- Day of the current object
    			-- (from DATE_TIME_MEASUREMENT)
    		require -- from  DATE_MEASUREMENT
    			True
    		ensure -- from DATE_TIME_MEASUREMENT
    			same_day: Result = date.day

    	days: INTEGER_32
    			-- Number of days elapsed since Origin

    	days_in_i_th_month (i, y: INTEGER_32): INTEGER_32
    			-- Number of days in the `i' th month at year `y'
    			-- (from DATE_CONSTANTS)
    		require -- from DATE_CONSTANTS
    			i_large_enough: i >= 1
    			i_small_enough: i <= months_in_year

    	days_in_leap_year: INTEGER_32 is 366
    			-- Number of days in a leap year
    			-- (from DATE_CONSTANTS)

    	days_in_non_leap_year: INTEGER_32 is 365
    			-- Number of days in a non-leap year
    			-- (from DATE_CONSTANTS)

    	days_in_week: INTEGER_32 is 7
    			-- Number of days in a week
    			-- (from DATE_CONSTANTS)

    	days_text: ARRAY [STRING_8]
    			-- Short text representation of days
    			-- (from DATE_CONSTANTS)

    	default_format_string: STRING_8
    			-- Default output format string
    			-- (from TIME_UTILITY)

    	fine_second: REAL_64
    			-- Representation of second with decimals
    			-- (from DATE_TIME_MEASUREMENT)
    		require -- from  TIME_MEASUREMENT
    			True
    		ensure -- from DATE_TIME_MEASUREMENT
    			same_fine_second: Result = time.fine_second

    	generating_type: STRING_8
    			-- Name of current object's generating type
    			-- (type of which it is a direct instance)
    			-- (from ANY)

    	generator: STRING_8
    			-- Name of current object's generating class
    			-- (base class of the type of which it is a direct instance)
    			-- (from ANY)

    	hour: INTEGER_32
    			-- Hour of the current object
    			-- (from DATE_TIME_MEASUREMENT)
    		require -- from  TIME_MEASUREMENT
    			True
    		ensure -- from DATE_TIME_MEASUREMENT
    			same_hour: Result = time.hour

    	hours_in_day: INTEGER_32 is 24
    			-- Number of hours in a day
    			-- (from TIME_CONSTANTS)

    	long_days_text: ARRAY [STRING_8]
    			-- Long text representation of days
    			-- (from DATE_CONSTANTS)

    	long_months_text: ARRAY [STRING_8]
    			-- Long text representation of months
    			-- (from DATE_CONSTANTS)

    	max_weeks_in_year: INTEGER_32 is 53
    			-- Maximun number of weeks in a year
    			-- (from DATE_CONSTANTS)

    	minute: INTEGER_32
    			-- Minute of the current object
    			-- (from DATE_TIME_MEASUREMENT)
    		require -- from  TIME_MEASUREMENT
    			True
    		ensure -- from DATE_TIME_MEASUREMENT
    			same_minute: Result = time.minute

    	minutes_in_hour: INTEGER_32 is 60
    			-- Number of minutes in an hour
    			-- (from TIME_CONSTANTS)

    	month: INTEGER_32
    			-- Month of the current object
    			-- (from DATE_TIME_MEASUREMENT)
    		require -- from  DATE_MEASUREMENT
    			True
    		ensure -- from DATE_TIME_MEASUREMENT
    			same_month: Result = date.month

    	months_in_year: INTEGER_32 is 12
    			-- Number of months in year
    			-- (from DATE_CONSTANTS)

    	months_text: ARRAY [STRING_8]
    			-- Short text representation of months
    			-- (from DATE_CONSTANTS)

    	origin: DATE_TIME
    			-- Origin date with origin time
    		ensure -- from ABSOLUTE
    			result_exists: Result /= Void

    	second: INTEGER_32
    			-- Second of the current object
    			-- (from DATE_TIME_MEASUREMENT)
    		require -- from  TIME_MEASUREMENT
    			True
    		ensure -- from DATE_TIME_MEASUREMENT
    			same_second: Result = time.second

    	seconds: INTEGER_32
    			-- Number of seconds elapsed from midnight of the current date

    	seconds_in_day: INTEGER_32 is 86400
    			-- Number of seconds in an hour
    			-- (from TIME_CONSTANTS)

    	seconds_in_hour: INTEGER_32 is 3600
    			-- Number of seconds in an hour
    			-- (from TIME_CONSTANTS)

    	seconds_in_minute: INTEGER_32 is 60
    			-- Number of seconds in a minute
    			-- (from TIME_CONSTANTS)

    	time: TIME
    			-- Time of the current object

    	time_default_format_string: STRING_8
    			-- Default output format for times
    			-- (from TIME_CONSTANTS)

    	time_duration: TIME_DURATION
    			-- Duration elapsed from midnight of the current date

    	year: INTEGER_32
    			-- Year of the current object
    			-- (from DATE_TIME_MEASUREMENT)
    		require -- from  DATE_MEASUREMENT
    			True
    		ensure -- from DATE_TIME_MEASUREMENT
    			same_year: Result = date.year

    feature -- Comparison

    	frozen deep_equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void
    			-- or attached to isomorphic object structures?
    			-- (from ANY)
    		ensure -- from ANY
    			shallow_implies_deep: standard_equal (some, other) implies Result
    			both_or_none_void: (some = Void) implies (Result = (other = Void))
    			same_type: (Result and (some /= Void)) implies some.same_type (other)
    			symmetric: Result implies deep_equal (other, some)

    	frozen equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void or attached
    			-- to objects considered equal?
    			-- (from ANY)
    		ensure -- from ANY
    			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

    	is_equal (other: like Current): BOOLEAN
    			-- Is the current object equal to `other'?
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			symmetric: Result implies other.is_equal (Current)
    			consistent: standard_is_equal (other) implies Result
    		ensure then -- from COMPARABLE
    			trichotomy: Result = (not (Current < other) and not (other < Current))

    	max (other: like Current): like Current
    			-- The greater of current object and `other'
    			-- (from COMPARABLE)
    		require -- from COMPARABLE
    			other_exists: other /= Void
    		ensure -- from COMPARABLE
    			current_if_not_smaller: Current >= other implies Result = Current
    			other_if_smaller: Current < other implies Result = other

    	min (other: like Current): like Current
    			-- The smaller of current object and `other'
    			-- (from COMPARABLE)
    		require -- from COMPARABLE
    			other_exists: other /= Void
    		ensure -- from COMPARABLE
    			current_if_not_greater: Current <= other implies Result = Current
    			other_if_greater: Current > other implies Result = other

    	frozen standard_equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void or attached to
    			-- field-by-field identical objects of the same type?
    			-- Always uses default object comparison criterion.
    			-- (from ANY)
    		ensure -- from ANY
    			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

    	frozen standard_is_equal (other: like Current): BOOLEAN
    			-- Is `other' attached to an object of the same type
    			-- as current object, and field-by-field identical to it?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			same_type: Result implies same_type (other)
    			symmetric: Result implies other.standard_is_equal (Current)

    	three_way_comparison (other: like Current): INTEGER_32
    			-- If current object equal to `other', 0;
    			-- if smaller, -1; if greater, 1
    			-- (from COMPARABLE)
    		require -- from COMPARABLE
    			other_exists: other /= Void
    		ensure -- from COMPARABLE
    			equal_zero: (Result = 0) = is_equal (other)
    			smaller_negative: (Result = -1) = (Current < other)
    			greater_positive: (Result = 1) = (Current > other)

    	infix "<" (other: like Current): BOOLEAN
    			-- Is the current object before `other'?
    		require -- from PART_COMPARABLE
    			other_exists: other /= Void
    		ensure then -- from COMPARABLE
    			asymmetric: Result implies not (other < Current)

    	infix "<=" (other: like Current): BOOLEAN
    			-- Is current object less than or equal to `other'?
    			-- (from COMPARABLE)
    		require -- from PART_COMPARABLE
    			other_exists: other /= Void
    		ensure then -- from COMPARABLE
    			definition: Result = ((Current < other) or is_equal (other))

    	infix ">" (other: like Current): BOOLEAN
    			-- Is current object greater than `other'?
    			-- (from COMPARABLE)
    		require -- from PART_COMPARABLE
    			other_exists: other /= Void
    		ensure then -- from COMPARABLE
    			definition: Result = (other < Current)

    	infix ">=" (other: like Current): BOOLEAN
    			-- Is current object greater than or equal to `other'?
    			-- (from COMPARABLE)
    		require -- from PART_COMPARABLE
    			other_exists: other /= Void
    		ensure then -- from COMPARABLE
    			definition: Result = (other <= Current)

    feature -- Status report

    	conforms_to (other: ANY): BOOLEAN
    			-- Does type of current object conform to type
    			-- of `other' (as per Eiffel: The Language, chapter 13)?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void

    	is_leap_year (y: INTEGER_32): BOOLEAN
    			-- Is year `y' a leap year?
    			-- (from DATE_CONSTANTS)

    	same_type (other: ANY): BOOLEAN
    			-- Is type of current object identical to type of `other'?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			definition: Result = (conforms_to (other) and other.conforms_to (Current))

    feature -- Duplication

    	frozen deep_copy (other: like Current)
    			-- Effect equivalent to that of:
    			--		copy (`other' . deep_twin)
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, other)

    	frozen deep_twin: like Current
    			-- New object structure recursively duplicated from Current.
    			-- (from ANY)
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, Result)

    	frozen standard_copy (other: like Current)
    			-- Copy every field of `other' onto corresponding field
    			-- of current object.
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    			type_identity: same_type (other)
    		ensure -- from ANY
    			is_standard_equal: standard_is_equal (other)

    	frozen standard_twin: like Current
    			-- New object field-by-field identical to `other'.
    			-- Always uses default copying semantics.
    			-- (from ANY)
    		ensure -- from ANY
    			standard_twin_not_void: Result /= Void
    			equal: standard_equal (Result, Current)

    	frozen twin: like Current
    			-- New object equal to `Current'
    			-- twin calls copy; to change copying/twining semantics, redefine copy.
    			-- (from ANY)
    		ensure -- from ANY
    			twin_not_void: Result /= Void
    			is_equal: Result.is_equal (Current)

    feature -- Basic operations

    	add (dtd: DATE_TIME_DURATION)
    			-- Adds `dtd' to current duration

    	day_add (d: INTEGER_32)
    			-- Add `d' days to the current date.
    		ensure
    			days_set: days = old days + d

    	frozen default: like Current
    			-- Default value of object's type
    			-- (from ANY)

    	frozen default_pointer: POINTER
    			-- Default value of type `POINTER'
    			-- (Avoid the need to write `p'.default for
    			-- some `p' of type `POINTER'.)
    			-- (from ANY)

    	default_rescue
    			-- Process exception for routines with no Rescue clause.
    			-- (Default: do nothing.)
    			-- (from ANY)

    	definite_duration (other: like Current): DATE_TIME_DURATION
    			-- Duration from `other' to the current date, converted to a
    			-- definite duration
    		require
    			other_exists: other /= Void
    		ensure
    			definite_result: Result.definite

    	frozen do_nothing
    			-- Execute a null action.
    			-- (from ANY)

    	fine_second_add (s: REAL_64)
    			-- Add `s' seconds to the current object.
    			-- if `s' has decimals, fractional_second from time is modified.

    	hour_add (h: INTEGER_32)
    			-- Add `h' hours to the current time.

    	minute_add (m: INTEGER_32)
    			-- Add `m' minutes to the current time.

    	relative_duration (other: like Current): DATE_TIME_DURATION
    			-- Duration from `other' to current date
    		require -- from ABSOLUTE
    			other_exists: other /= Void
    		ensure -- from ABSOLUTE
    			result_exists: Result /= Void
    		ensure then
    			origin_set: equal (other, Result.origin_date_time)

    	second_add (s: INTEGER_32)
    			-- Add `s' seconds to the current time.

    	infix "+" (d: DATE_TIME_DURATION): like Current
    			-- Sum the current object with `d'
    		ensure
    			result_exists: Result /= Void

    	infix "-" (other: like Current): INTERVAL [DATE_TIME]
    			-- Interval between current object and `other'
    			-- (from ABSOLUTE)
    		require -- from ABSOLUTE
    			other_exists: other /= Void
    			other_smaller_than_current: other <= Current
    		ensure -- from ABSOLUTE
    			result_exists: Result /= Void
    			result_set: Result.start_bound.is_equal (other) and then Result.end_bound.is_equal (Current)

    feature -- Access

    	fractional_second: REAL_64
    			-- Fractional part of fine_second
    			-- (from TIME_VALUE)

    feature -- Element Change

    	copy (other: like Current)
    			-- set date and time with the `other' attributes.
    		require -- from ANY
    			other_not_void: other /= Void
    			type_identity: same_type (other)
    		ensure -- from ANY
    			is_equal: is_equal (other)

    	set_date (d: DATE)
    			-- Set date to `d'.
    		require
    			d_exists: d /= Void
    		ensure
    			date_set: date = d

    	set_time (t: TIME)
    			-- Set time to `t'.
    		require
    			t_exists: t /= Void
    		ensure
    			time_set: time = t

    feature -- Initialization

    	make (y, mo, d, h, mi, s: INTEGER_32)
    			-- Set year, month day to `y', `mo', `d'.
    			-- Set hour, minute, second to `h', `mi', `s'.
    		require
    			correct_date_time: is_correct_date_time (y, mo, d, h, mi, s, False)
    		ensure
    			year_set: year = y
    			month_set: month = mo
    			day_set: day = d
    			hour_set: hour = h
    			minute_set: minute = mi
    			second_set: second = s

    	make_by_date (d: DATE)
    			-- Set date to `d' and time to origin of time.
    		require
    			d_exists: d /= Void
    		ensure
    			date_set: date = d
    			time_set: time.is_equal (time.origin)

    	make_by_date_time (d: DATE; t: TIME)
    			-- Set date to `d' and time to `t'
    		require
    			d_exists: d /= Void
    			t_exists: t /= Void
    		ensure
    			date_set: date = d
    			time_set: time = t

    	make_fine (y, mo, d, h, mi: INTEGER_32; s: REAL_64)
    			-- Set year, month day to `y', `mo', `d'.
    			-- Set hour, minute, second to `h', `m', `s'.
    		require
    			correct_date_time: is_correct_date_time (y, mo, d, h, mi, s, False)
    		ensure
    			year_set: year = y
    			month_set: month = mo
    			day_set: day = d
    			hour_set: hour = h
    			minute_set: minute = mi
    			second_set: fine_second = s

    	make_from_string (s: STRING_8; code: STRING_8)
    			-- Initialize from a "standard" string of form
    			-- `code'.
    			-- (For 2-digit year specifications, the current century is used as
    			-- base century.)
    		require
    			s_exists: s /= Void
    			c_exists: code /= Void
    			date_time_valid: date_time_valid (s, code)

    	make_from_string_default (s: STRING_8)
    			-- Initialize from a "standard" string of form
    			-- default_format_string.
    			-- (For 2-digit year specifications, the current century is used as
    			-- base century.)
    		require
    			s_exists: s /= Void
    			date_time_valid: date_time_valid (s, default_format_string)

    	make_from_string_default_with_base (s: STRING_8; base: INTEGER_32)
    			-- Initialize from a "standard" string of form
    			-- default_format_string with base century `base'.
    		require
    			s_exists: s /= Void
    			base_valid: base > 0 and (base \\ 100 = 0)
    			date_time_valid: date_time_valid_with_base (s, default_format_string, base)

    	make_from_string_with_base (s: STRING_8; code: STRING_8; base: INTEGER_32)
    			-- Initialize from a "standard" string of form
    			-- `code' with base century `base'.
    		require
    			s_exists: s /= Void
    			c_exists: code /= Void
    			base_valid: base > 0 and (base \\ 100 = 0)
    			date_time_valid: date_time_valid_with_base (s, code, base)

    	make_now
    			-- Get the date and the time from the system.

    	make_now_utc
    			-- Get the date and the time from the system.

    feature -- Measurement

    	duration: DATE_TIME_DURATION
    			-- Definite duration elapsed from Origin
    		require -- from  ABSOLUTE
    			True
    		ensure then
    			definite_result: Result.definite

    feature -- Output

    	formatted_out (s: STRING_8): STRING_8
    			-- Printable representation of the current object
    			-- With "standard" form: `s'
    		require
    			s_exists: s /= Void

    	io: STD_FILES
    			-- Handle to standard file setup
    			-- (from ANY)

    	out: STRING_8
    			-- Printable representation of the current object
    			-- With "standard" form: default_format_string

    	print (some: ANY)
    			-- Write terse external representation of `some'
    			-- on standard output.
    			-- (from ANY)

    	frozen tagged_out: STRING_8
    			-- New string containing terse printable representation
    			-- of current object
    			-- Was declared in ANY as synonym of out.
    			-- (from ANY)

    feature -- Platform

    	operating_environment: OPERATING_ENVIRONMENT
    			-- Objects available from the operating system
    			-- (from ANY)

    feature -- Preconditions

    	date_time_valid (s: STRING_8; code_string: STRING_8): BOOLEAN
    			-- Is the code_string enough precise
    			-- To create an instance of type DATE_TIME
    			-- And does the string `s' correspond to `code_string'?
    			-- (from DATE_TIME_VALIDITY_CHECKER)
    		require -- from DATE_TIME_VALIDITY_CHECKER
    			s_exists: s /= Void
    			code_exists: code_string /= Void

    	date_time_valid_with_base (s: STRING_8; code_string: STRING_8; base: INTEGER_32): BOOLEAN
    			-- Is the code_string enough precise
    			-- To create an instance of type DATE_TIME
    			-- And does the string `s' correspond to `code_string'?
    			-- Use base century `base'.
    			-- (from DATE_TIME_VALIDITY_CHECKER)
    		require -- from DATE_TIME_VALIDITY_CHECKER
    			s_exists: s /= Void
    			code_exists: code_string /= Void
    			base_valid: base > 0 and (base \\ 100 = 0)

    	is_correct_date_time (y, mo, d, h, mi: INTEGER_32; s: REAL_64; twelve_hour_scale: BOOLEAN): BOOLEAN
    			-- Is date-time specified by `y', `mo', `d', `h', `mi', `s'
    			-- correct?
    			-- `twelve_hour_scale' specifies if the hour range is 1 - 12
    			-- (if True) or 0 - 23 (if False).
    			-- (from DATE_TIME_VALIDITY_CHECKER)

    invariant
    		-- from COMPARABLE
    	irreflexive_comparison: not (Current < Current)

    		-- from ANY
    	reflexive_equality: standard_is_equal (Current)
    	reflexive_conformance: conforms_to (Current)

    		-- from DATE_TIME_MEASUREMENT
    	date_exists: date /= Void
    	time_exists: time /= Void

    indexing
    	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
    	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
    	source: "[
    		Eiffel Software
    		356 Storke Road, Goleta, CA 93117 USA
    		Telephone 805-685-1006, Fax 805-685-6869
    		Website http://www.eiffel.com
    		Customer support http://support.eiffel.com
    	]"

    end -- class DATE_TIME