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