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diff --git a/ruby_1_8_6/lib/date.rb b/ruby_1_8_6/lib/date.rb new file mode 100644 index 0000000000..6da4d6aa8e --- /dev/null +++ b/ruby_1_8_6/lib/date.rb @@ -0,0 +1,1708 @@ +# +# date.rb - date and time library +# +# Author: Tadayoshi Funaba 1998-2006 +# +# Documentation: William Webber <william@williamwebber.com> +# +#-- +# $Id: date.rb,v 2.30 2006-12-30 21:43:41+09 tadf Exp $ +#++ +# +# == Overview +# +# This file provides two classes for working with +# dates and times. +# +# The first class, Date, represents dates. +# It works with years, months, weeks, and days. +# See the Date class documentation for more details. +# +# The second, DateTime, extends Date to include hours, +# minutes, seconds, and fractions of a second. It +# provides basic support for time zones. See the +# DateTime class documentation for more details. +# +# === Ways of calculating the date. +# +# In common usage, the date is reckoned in years since or +# before the Common Era (CE/BCE, also known as AD/BC), then +# as a month and day-of-the-month within the current year. +# This is known as the *Civil* *Date*, and abbreviated +# as +civil+ in the Date class. +# +# Instead of year, month-of-the-year, and day-of-the-month, +# the date can also be reckoned in terms of year and +# day-of-the-year. This is known as the *Ordinal* *Date*, +# and is abbreviated as +ordinal+ in the Date class. (Note +# that referring to this as the Julian date is incorrect.) +# +# The date can also be reckoned in terms of year, week-of-the-year, +# and day-of-the-week. This is known as the *Commercial* +# *Date*, and is abbreviated as +commercial+ in the +# Date class. The commercial week runs Monday (day-of-the-week +# 1) to Sunday (day-of-the-week 7), in contrast to the civil +# week which runs Sunday (day-of-the-week 0) to Saturday +# (day-of-the-week 6). The first week of the commercial year +# starts on the Monday on or before January 1, and the commercial +# year itself starts on this Monday, not January 1. +# +# For scientific purposes, it is convenient to refer to a date +# simply as a day count, counting from an arbitrary initial +# day. The date first chosen for this was January 1, 4713 BCE. +# A count of days from this date is the *Julian* *Day* *Number* +# or *Julian* *Date*, which is abbreviated as +jd+ in the +# Date class. This is in local time, and counts from midnight +# on the initial day. The stricter usage is in UTC, and counts +# from midday on the initial day. This is referred to in the +# Date class as the *Astronomical* *Julian* *Day* *Number*, and +# abbreviated as +ajd+. In the Date class, the Astronomical +# Julian Day Number includes fractional days. +# +# Another absolute day count is the *Modified* *Julian* *Day* +# *Number*, which takes November 17, 1858 as its initial day. +# This is abbreviated as +mjd+ in the Date class. There +# is also an *Astronomical* *Modified* *Julian* *Day* *Number*, +# which is in UTC and includes fractional days. This is +# abbreviated as +amjd+ in the Date class. Like the Modified +# Julian Day Number (and unlike the Astronomical Julian +# Day Number), it counts from midnight. +# +# Alternative calendars such as the Chinese Lunar Calendar, +# the Islamic Calendar, or the French Revolutionary Calendar +# are not supported by the Date class; nor are calendars that +# are based on an Era different from the Common Era, such as +# the Japanese Imperial Calendar or the Republic of China +# Calendar. +# +# === Calendar Reform +# +# The standard civil year is 365 days long. However, the +# solar year is fractionally longer than this. To account +# for this, a *leap* *year* is occasionally inserted. This +# is a year with 366 days, the extra day falling on February 29. +# In the early days of the civil calendar, every fourth +# year without exception was a leap year. This way of +# reckoning leap years is the *Julian* *Calendar*. +# +# However, the solar year is marginally shorter than 365 1/4 +# days, and so the *Julian* *Calendar* gradually ran slow +# over the centuries. To correct this, every 100th year +# (but not every 400th year) was excluded as a leap year. +# This way of reckoning leap years, which we use today, is +# the *Gregorian* *Calendar*. +# +# The Gregorian Calendar was introduced at different times +# in different regions. The day on which it was introduced +# for a particular region is the *Day* *of* *Calendar* +# *Reform* for that region. This is abbreviated as +sg+ +# (for Start of Gregorian calendar) in the Date class. +# +# Two such days are of particular +# significance. The first is October 15, 1582, which was +# the Day of Calendar Reform for Italy and most Catholic +# countries. The second is September 14, 1752, which was +# the Day of Calendar Reform for England and its colonies +# (including what is now the United States). These two +# dates are available as the constants Date::ITALY and +# Date::ENGLAND, respectively. (By comparison, Germany and +# Holland, less Catholic than Italy but less stubborn than +# England, changed over in 1698; Sweden in 1753; Russia not +# till 1918, after the Revolution; and Greece in 1923. Many +# Orthodox churches still use the Julian Calendar. A complete +# list of Days of Calendar Reform can be found at +# http://www.polysyllabic.com/GregConv.html.) +# +# Switching from the Julian to the Gregorian calendar +# involved skipping a number of days to make up for the +# accumulated lag, and the later the switch was (or is) +# done, the more days need to be skipped. So in 1582 in Italy, +# 4th October was followed by 15th October, skipping 10 days; in 1752 +# in England, 2nd September was followed by 14th September, skipping +# 11 days; and if I decided to switch from Julian to Gregorian +# Calendar this midnight, I would go from 27th July 2003 (Julian) +# today to 10th August 2003 (Gregorian) tomorrow, skipping +# 13 days. The Date class is aware of this gap, and a supposed +# date that would fall in the middle of it is regarded as invalid. +# +# The Day of Calendar Reform is relevant to all date representations +# involving years. It is not relevant to the Julian Day Numbers, +# except for converting between them and year-based representations. +# +# In the Date and DateTime classes, the Day of Calendar Reform or +# +sg+ can be specified a number of ways. First, it can be as +# the Julian Day Number of the Day of Calendar Reform. Second, +# it can be using the constants Date::ITALY or Date::ENGLAND; these +# are in fact the Julian Day Numbers of the Day of Calendar Reform +# of the respective regions. Third, it can be as the constant +# Date::JULIAN, which means to always use the Julian Calendar. +# Finally, it can be as the constant Date::GREGORIAN, which means +# to always use the Gregorian Calendar. +# +# Note: in the Julian Calendar, New Years Day was March 25. The +# Date class does not follow this convention. +# +# === Time Zones +# +# DateTime objects support a simple representation +# of time zones. Time zones are represented as an offset +# from UTC, as a fraction of a day. This offset is the +# how much local time is later (or earlier) than UTC. +# UTC offset 0 is centred on England (also known as GMT). +# As you travel east, the offset increases until you +# reach the dateline in the middle of the Pacific Ocean; +# as you travel west, the offset decreases. This offset +# is abbreviated as +of+ in the Date class. +# +# This simple representation of time zones does not take +# into account the common practice of Daylight Savings +# Time or Summer Time. +# +# Most DateTime methods return the date and the +# time in local time. The two exceptions are +# #ajd() and #amjd(), which return the date and time +# in UTC time, including fractional days. +# +# The Date class does not support time zone offsets, in that +# there is no way to create a Date object with a time zone. +# However, methods of the Date class when used by a +# DateTime instance will use the time zone offset of this +# instance. +# +# == Examples of use +# +# === Print out the date of every Sunday between two dates. +# +# def print_sundays(d1, d2) +# d1 +=1 while (d1.wday != 0) +# d1.step(d2, 7) do |date| +# puts "#{Date::MONTHNAMES[date.mon]} #{date.day}" +# end +# end +# +# print_sundays(Date::civil(2003, 4, 8), Date::civil(2003, 5, 23)) +# +# === Calculate how many seconds to go till midnight on New Year's Day. +# +# def secs_to_new_year(now = DateTime::now()) +# new_year = DateTime.new(now.year + 1, 1, 1) +# dif = new_year - now +# hours, mins, secs, ignore_fractions = Date::day_fraction_to_time(dif) +# return hours * 60 * 60 + mins * 60 + secs +# end +# +# puts secs_to_new_year() + +require 'rational' +require 'date/format' + +# Class representing a date. +# +# See the documentation to the file date.rb for an overview. +# +# Internally, the date is represented as an Astronomical +# Julian Day Number, +ajd+. The Day of Calendar Reform, +sg+, is +# also stored, for conversions to other date formats. (There +# is also an +of+ field for a time zone offset, but this +# is only for the use of the DateTime subclass.) +# +# A new Date object is created using one of the object creation +# class methods named after the corresponding date format, and the +# arguments appropriate to that date format; for instance, +# Date::civil() (aliased to Date::new()) with year, month, +# and day-of-month, or Date::ordinal() with year and day-of-year. +# All of these object creation class methods also take the +# Day of Calendar Reform as an optional argument. +# +# Date objects are immutable once created. +# +# Once a Date has been created, date values +# can be retrieved for the different date formats supported +# using instance methods. For instance, #mon() gives the +# Civil month, #cwday() gives the Commercial day of the week, +# and #yday() gives the Ordinal day of the year. Date values +# can be retrieved in any format, regardless of what format +# was used to create the Date instance. +# +# The Date class includes the Comparable module, allowing +# date objects to be compared and sorted, ranges of dates +# to be created, and so forth. +class Date + + include Comparable + + # Full month names, in English. Months count from 1 to 12; a + # month's numerical representation indexed into this array + # gives the name of that month (hence the first element is nil). + MONTHNAMES = [nil] + %w(January February March April May June July + August September October November December) + + # Full names of days of the week, in English. Days of the week + # count from 0 to 6 (except in the commercial week); a day's numerical + # representation indexed into this array gives the name of that day. + DAYNAMES = %w(Sunday Monday Tuesday Wednesday Thursday Friday Saturday) + + # Abbreviated month names, in English. + ABBR_MONTHNAMES = [nil] + %w(Jan Feb Mar Apr May Jun + Jul Aug Sep Oct Nov Dec) + + # Abbreviated day names, in English. + ABBR_DAYNAMES = %w(Sun Mon Tue Wed Thu Fri Sat) + + [MONTHNAMES, DAYNAMES, ABBR_MONTHNAMES, ABBR_DAYNAMES].each do |xs| + xs.each{|x| x.freeze}.freeze + end + + class Infinity < Numeric # :nodoc: + + include Comparable + + def initialize(d=1) @d = d <=> 0 end + + def d() @d end + + protected :d + + def zero? () false end + def finite? () false end + def infinite? () d.nonzero? end + def nan? () d.zero? end + + def abs() self.class.new end + + def -@ () self.class.new(-d) end + def +@ () self.class.new(+d) end + + def <=> (other) + case other + when Infinity; d <=> other.d + when Numeric; d + else + begin + l, r = other.coerce(self) + return l <=> r + rescue NoMethodError + end + end + nil + end + + def coerce(other) + case other + when Numeric; return -d, d + else + super + end + end + + end + + # The Julian Day Number of the Day of Calendar Reform for Italy + # and the Catholic countries. + ITALY = 2299161 # 1582-10-15 + + # The Julian Day Number of the Day of Calendar Reform for England + # and her Colonies. + ENGLAND = 2361222 # 1752-09-14 + + # A constant used to indicate that a Date should always use the + # Julian calendar. + JULIAN = Infinity.new + + # A constant used to indicate that a Date should always use the + # Gregorian calendar. + GREGORIAN = -Infinity.new + + UNIXEPOCH = 2440588 # 1970-01-01 :nodoc: + + # Does a given Julian Day Number fall inside the old-style (Julian) + # calendar? + # + # +jd+ is the Julian Day Number in question. +sg+ may be Date::GREGORIAN, + # in which case the answer is false; it may be Date::JULIAN, in which case + # the answer is true; or it may a number representing the Day of + # Calendar Reform. Date::ENGLAND and Date::ITALY are two possible such + # days. + + def self.julian? (jd, sg) + case sg + when Numeric + jd < sg + else + if $VERBOSE + warn("#{caller.shift.sub(/:in .*/, '')}: " \ +"warning: do not use non-numerical object as julian day number anymore") + end + not sg + end + end + + # Does a given Julian Day Number fall inside the new-style (Gregorian) + # calendar? + # + # The reverse of self.os? See the documentation for that method for + # more details. + def self.gregorian? (jd, sg) !julian?(jd, sg) end + + def self.fix_style(jd, sg) # :nodoc: + if julian?(jd, sg) + then JULIAN + else GREGORIAN end + end + + private_class_method :fix_style + + # Convert an Ordinal Date to a Julian Day Number. + # + # +y+ and +d+ are the year and day-of-year to convert. + # +sg+ specifies the Day of Calendar Reform. + # + # Returns the corresponding Julian Day Number. + def self.ordinal_to_jd(y, d, sg=GREGORIAN) + civil_to_jd(y, 1, d, sg) + end + + # Convert a Julian Day Number to an Ordinal Date. + # + # +jd+ is the Julian Day Number to convert. + # +sg+ specifies the Day of Calendar Reform. + # + # Returns the corresponding Ordinal Date as + # [year, day_of_year] + def self.jd_to_ordinal(jd, sg=GREGORIAN) + y = jd_to_civil(jd, sg)[0] + doy = jd - civil_to_jd(y - 1, 12, 31, fix_style(jd, sg)) + return y, doy + end + + # Convert a Civil Date to a Julian Day Number. + # +y+, +m+, and +d+ are the year, month, and day of the + # month. +sg+ specifies the Day of Calendar Reform. + # + # Returns the corresponding Julian Day Number. + def self.civil_to_jd(y, m, d, sg=GREGORIAN) + if m <= 2 + y -= 1 + m += 12 + end + a = (y / 100.0).floor + b = 2 - a + (a / 4.0).floor + jd = (365.25 * (y + 4716)).floor + + (30.6001 * (m + 1)).floor + + d + b - 1524 + if julian?(jd, sg) + jd -= b + end + jd + end + + # Convert a Julian Day Number to a Civil Date. +jd+ is + # the Julian Day Number. +sg+ specifies the Day of + # Calendar Reform. + # + # Returns the corresponding [year, month, day_of_month] + # as a three-element array. + def self.jd_to_civil(jd, sg=GREGORIAN) + if julian?(jd, sg) + a = jd + else + x = ((jd - 1867216.25) / 36524.25).floor + a = jd + 1 + x - (x / 4.0).floor + end + b = a + 1524 + c = ((b - 122.1) / 365.25).floor + d = (365.25 * c).floor + e = ((b - d) / 30.6001).floor + dom = b - d - (30.6001 * e).floor + if e <= 13 + m = e - 1 + y = c - 4716 + else + m = e - 13 + y = c - 4715 + end + return y, m, dom + end + + # Convert a Commercial Date to a Julian Day Number. + # + # +y+, +w+, and +d+ are the (commercial) year, week of the year, + # and day of the week of the Commercial Date to convert. + # +sg+ specifies the Day of Calendar Reform. + def self.commercial_to_jd(y, w, d, ns=GREGORIAN) + jd = civil_to_jd(y, 1, 4, ns) + (jd - (((jd - 1) + 1) % 7)) + + 7 * (w - 1) + + (d - 1) + end + + # Convert a Julian Day Number to a Commercial Date + # + # +jd+ is the Julian Day Number to convert. + # +sg+ specifies the Day of Calendar Reform. + # + # Returns the corresponding Commercial Date as + # [commercial_year, week_of_year, day_of_week] + def self.jd_to_commercial(jd, sg=GREGORIAN) + ns = fix_style(jd, sg) + a = jd_to_civil(jd - 3, ns)[0] + y = if jd >= commercial_to_jd(a + 1, 1, 1, ns) then a + 1 else a end + w = 1 + ((jd - commercial_to_jd(y, 1, 1, ns)) / 7).floor + d = (jd + 1) % 7 + d = 7 if d == 0 + return y, w, d + end + + def self.weeknum_to_jd(y, w, d, f=0, ns=GREGORIAN) # :nodoc: + a = civil_to_jd(y, 1, 1, ns) + 6 + (a - ((a - f) + 1) % 7 - 7) + 7 * w + d + end + + def self.jd_to_weeknum(jd, f=0, sg=GREGORIAN) # :nodoc: + ns = fix_style(jd, sg) + y, m, d = jd_to_civil(jd, ns) + a = civil_to_jd(y, 1, 1, ns) + 6 + w, d = (jd - (a - ((a - f) + 1) % 7) + 7).divmod(7) + return y, w, d + end + + private_class_method :weeknum_to_jd, :jd_to_weeknum + + # Convert an Astronomical Julian Day Number to a (civil) Julian + # Day Number. + # + # +ajd+ is the Astronomical Julian Day Number to convert. + # +of+ is the offset from UTC as a fraction of a day (defaults to 0). + # + # Returns the (civil) Julian Day Number as [day_number, + # fraction] where +fraction+ is always 1/2. + def self.ajd_to_jd(ajd, of=0) (ajd + of + 1.to_r/2).divmod(1) end + + # Convert a (civil) Julian Day Number to an Astronomical Julian + # Day Number. + # + # +jd+ is the Julian Day Number to convert, and +fr+ is a + # fractional day. + # +of+ is the offset from UTC as a fraction of a day (defaults to 0). + # + # Returns the Astronomical Julian Day Number as a single + # numeric value. + def self.jd_to_ajd(jd, fr, of=0) jd + fr - of - 1.to_r/2 end + + # Convert a fractional day +fr+ to [hours, minutes, seconds, + # fraction_of_a_second] + def self.day_fraction_to_time(fr) + h, fr = fr.divmod(1.to_r/24) + min, fr = fr.divmod(1.to_r/1440) + s, fr = fr.divmod(1.to_r/86400) + return h, min, s, fr + end + + # Convert an +h+ hour, +min+ minutes, +s+ seconds period + # to a fractional day. + def self.time_to_day_fraction(h, min, s) + h.to_r/24 + min.to_r/1440 + s.to_r/86400 + end + + # Convert an Astronomical Modified Julian Day Number to an + # Astronomical Julian Day Number. + def self.amjd_to_ajd(amjd) amjd + 4800001.to_r/2 end + + # Convert an Astronomical Julian Day Number to an + # Astronomical Modified Julian Day Number. + def self.ajd_to_amjd(ajd) ajd - 4800001.to_r/2 end + + # Convert a Modified Julian Day Number to a Julian + # Day Number. + def self.mjd_to_jd(mjd) mjd + 2400001 end + + # Convert a Julian Day Number to a Modified Julian Day + # Number. + def self.jd_to_mjd(jd) jd - 2400001 end + + # Convert a count of the number of days since the adoption + # of the Gregorian Calendar (in Italy) to a Julian Day Number. + def self.ld_to_jd(ld) ld + 2299160 end + + # Convert a Julian Day Number to the number of days since + # the adoption of the Gregorian Calendar (in Italy). + def self.jd_to_ld(jd) jd - 2299160 end + + # Convert a Julian Day Number to the day of the week. + # + # Sunday is day-of-week 0; Saturday is day-of-week 6. + def self.jd_to_wday(jd) (jd + 1) % 7 end + + # Is a year a leap year in the Julian calendar? + # + # All years divisible by 4 are leap years in the Julian calendar. + def self.julian_leap? (y) y % 4 == 0 end + + # Is a year a leap year in the Gregorian calendar? + # + # All years divisible by 4 are leap years in the Gregorian calendar, + # except for years divisible by 100 and not by 400. + def self.gregorian_leap? (y) y % 4 == 0 && y % 100 != 0 || y % 400 == 0 end + + class << self; alias_method :leap?, :gregorian_leap? end + class << self; alias_method :new!, :new end + + # Is +jd+ a valid Julian Day Number? + # + # If it is, returns it. In fact, any value is treated as a valid + # Julian Day Number. + def self.valid_jd? (jd, sg=ITALY) jd end + + # Do the year +y+ and day-of-year +d+ make a valid Ordinal Date? + # Returns the corresponding Julian Day Number if they do, or + # nil if they don't. + # + # +d+ can be a negative number, in which case it counts backwards + # from the end of the year (-1 being the last day of the year). + # No year wraparound is performed, however, so valid values of + # +d+ are -365 .. -1, 1 .. 365 on a non-leap-year, + # -366 .. -1, 1 .. 366 on a leap year. + # A date falling in the period skipped in the Day of Calendar Reform + # adjustment is not valid. + # + # +sg+ specifies the Day of Calendar Reform. + def self.valid_ordinal? (y, d, sg=ITALY) + if d < 0 + ny, = (y + 1).divmod(1) + jd = ordinal_to_jd(ny, d + 1, sg) + ns = fix_style(jd, sg) + return unless [y] == jd_to_ordinal(jd, sg)[0..0] + return unless [ny, 1] == jd_to_ordinal(jd - d, ns) + else + jd = ordinal_to_jd(y, d, sg) + return unless [y, d] == jd_to_ordinal(jd, sg) + end + jd + end + + # Do year +y+, month +m+, and day-of-month +d+ make a + # valid Civil Date? Returns the corresponding Julian + # Day Number if they do, nil if they don't. + # + # +m+ and +d+ can be negative, in which case they count + # backwards from the end of the year and the end of the + # month respectively. No wraparound is performed, however, + # and invalid values cause an ArgumentError to be raised. + # A date falling in the period skipped in the Day of Calendar + # Reform adjustment is not valid. + # + # +sg+ specifies the Day of Calendar Reform. + def self.valid_civil? (y, m, d, sg=ITALY) + if m < 0 + m += 13 + end + if d < 0 + ny, nm = (y * 12 + m).divmod(12) + nm, = (nm + 1).divmod(1) + jd = civil_to_jd(ny, nm, d + 1, sg) + ns = fix_style(jd, sg) + return unless [y, m] == jd_to_civil(jd, sg)[0..1] + return unless [ny, nm, 1] == jd_to_civil(jd - d, ns) + else + jd = civil_to_jd(y, m, d, sg) + return unless [y, m, d] == jd_to_civil(jd, sg) + end + jd + end + + class << self; alias_method :valid_date?, :valid_civil? end + + # Do year +y+, week-of-year +w+, and day-of-week +d+ make a + # valid Commercial Date? Returns the corresponding Julian + # Day Number if they do, nil if they don't. + # + # Monday is day-of-week 1; Sunday is day-of-week 7. + # + # +w+ and +d+ can be negative, in which case they count + # backwards from the end of the year and the end of the + # week respectively. No wraparound is performed, however, + # and invalid values cause an ArgumentError to be raised. + # A date falling in the period skipped in the Day of Calendar + # Reform adjustment is not valid. + # + # +sg+ specifies the Day of Calendar Reform. + def self.valid_commercial? (y, w, d, sg=ITALY) + if d < 0 + d += 8 + end + if w < 0 + ny, nw, nd = + jd_to_commercial(commercial_to_jd(y + 1, 1, 1) + w * 7) + return unless ny == y + w = nw + end + jd = commercial_to_jd(y, w, d) + return unless gregorian?(jd, sg) + return unless [y, w, d] == jd_to_commercial(jd) + jd + end + + def self.valid_weeknum? (y, w, d, f, sg=ITALY) # :nodoc: + if d < 0 + d += 7 + end + if w < 0 + ny, nw, nd, nf = + jd_to_weeknum(weeknum_to_jd(y + 1, 1, f, f) + w * 7, f) + return unless ny == y + w = nw + end + jd = weeknum_to_jd(y, w, d, f) + return unless gregorian?(jd, sg) + return unless [y, w, d] == jd_to_weeknum(jd, f) + jd + end + + private_class_method :valid_weeknum? + + # Do hour +h+, minute +min+, and second +s+ constitute a valid time? + # + # If they do, returns their value as a fraction of a day. If not, + # returns nil. + # + # The 24-hour clock is used. Negative values of +h+, +min+, and + # +sec+ are treating as counting backwards from the end of the + # next larger unit (e.g. a +min+ of -2 is treated as 58). No + # wraparound is performed. + def self.valid_time? (h, min, s) + h += 24 if h < 0 + min += 60 if min < 0 + s += 60 if s < 0 + return unless ((0..23) === h && + (0..59) === min && + (0..59) === s) || + (24 == h && + 0 == min && + 0 == s) + time_to_day_fraction(h, min, s) + end + + # Create a new Date object from a Julian Day Number. + # + # +jd+ is the Julian Day Number; if not specified, it defaults to + # 0. + # +sg+ specifies the Day of Calendar Reform. + def self.jd(jd=0, sg=ITALY) + jd = valid_jd?(jd, sg) + new!(jd_to_ajd(jd, 0, 0), 0, sg) + end + + # Create a new Date object from an Ordinal Date, specified + # by year +y+ and day-of-year +d+. +d+ can be negative, + # in which it counts backwards from the end of the year. + # No year wraparound is performed, however. An invalid + # value for +d+ results in an ArgumentError being raised. + # + # +y+ defaults to -4712, and +d+ to 1; this is Julian Day + # Number day 0. + # + # +sg+ specifies the Day of Calendar Reform. + def self.ordinal(y=-4712, d=1, sg=ITALY) + unless jd = valid_ordinal?(y, d, sg) + raise ArgumentError, 'invalid date' + end + new!(jd_to_ajd(jd, 0, 0), 0, sg) + end + + # Create a new Date object for the Civil Date specified by + # year +y+, month +m+, and day-of-month +d+. + # + # +m+ and +d+ can be negative, in which case they count + # backwards from the end of the year and the end of the + # month respectively. No wraparound is performed, however, + # and invalid values cause an ArgumentError to be raised. + # can be negative + # + # +y+ defaults to -4712, +m+ to 1, and +d+ to 1; this is + # Julian Day Number day 0. + # + # +sg+ specifies the Day of Calendar Reform. + def self.civil(y=-4712, m=1, d=1, sg=ITALY) + unless jd = valid_civil?(y, m, d, sg) + raise ArgumentError, 'invalid date' + end + new!(jd_to_ajd(jd, 0, 0), 0, sg) + end + + class << self; alias_method :new, :civil end + + # Create a new Date object for the Commercial Date specified by + # year +y+, week-of-year +w+, and day-of-week +d+. + # + # Monday is day-of-week 1; Sunday is day-of-week 7. + # + # +w+ and +d+ can be negative, in which case they count + # backwards from the end of the year and the end of the + # week respectively. No wraparound is performed, however, + # and invalid values cause an ArgumentError to be raised. + # + # +y+ defaults to 1582, +w+ to 41, and +d+ to 5, the Day of + # Calendar Reform for Italy and the Catholic countries. + # + # +sg+ specifies the Day of Calendar Reform. + def self.commercial(y=1582, w=41, d=5, sg=ITALY) + unless jd = valid_commercial?(y, w, d, sg) + raise ArgumentError, 'invalid date' + end + new!(jd_to_ajd(jd, 0, 0), 0, sg) + end + + def self.weeknum(y=1582, w=41, d=5, f=0, sg=ITALY) # :nodoc: + unless jd = valid_weeknum?(y, w, d, f, sg) + raise ArgumentError, 'invalid date' + end + new!(jd_to_ajd(jd, 0, 0), 0, sg) + end + + private_class_method :weeknum + + def self.rewrite_frags(elem) # :nodoc: + elem ||= {} + if seconds = elem[:seconds] + d, fr = seconds.divmod(86400) + h, fr = fr.divmod(3600) + min, fr = fr.divmod(60) + s, fr = fr.divmod(1) + elem[:jd] = UNIXEPOCH + d + elem[:hour] = h + elem[:min] = min + elem[:sec] = s + elem[:sec_fraction] = fr + elem.delete(:seconds) + elem.delete(:offset) + end + elem + end + + private_class_method :rewrite_frags + + def self.complete_frags(elem) # :nodoc: + i = 0 + g = [[:time, [:hour, :min, :sec]], + [nil, [:jd]], + [:ordinal, [:year, :yday, :hour, :min, :sec]], + [:civil, [:year, :mon, :mday, :hour, :min, :sec]], + [:commercial, [:cwyear, :cweek, :cwday, :hour, :min, :sec]], + [:wday, [:wday, :hour, :min, :sec]], + [:wnum0, [:year, :wnum0, :wday, :hour, :min, :sec]], + [:wnum1, [:year, :wnum1, :wday, :hour, :min, :sec]], + [nil, [:cwyear, :cweek, :wday, :hour, :min, :sec]], + [nil, [:year, :wnum0, :cwday, :hour, :min, :sec]], + [nil, [:year, :wnum1, :cwday, :hour, :min, :sec]]]. + collect{|k, a| e = elem.values_at(*a).compact; [k, a, e]}. + select{|k, a, e| e.size > 0}. + sort_by{|k, a, e| [e.size, i -= 1]}.last + + d = nil + + if g && g[0] && (g[1].size - g[2].size) != 0 + d ||= Date.today + + case g[0] + when :ordinal + elem[:year] ||= d.year + elem[:yday] ||= 1 + when :civil + g[1].each do |e| + break if elem[e] + elem[e] = d.__send__(e) + end + elem[:mon] ||= 1 + elem[:mday] ||= 1 + when :commercial + g[1].each do |e| + break if elem[e] + elem[e] = d.__send__(e) + end + elem[:cweek] ||= 1 + elem[:cwday] ||= 1 + when :wday + elem[:jd] ||= (d - d.wday + elem[:wday]).jd + when :wnum0 + g[1].each do |e| + break if elem[e] + elem[e] = d.__send__(e) + end + elem[:wnum0] ||= 0 + elem[:wday] ||= 0 + when :wnum1 + g[1].each do |e| + break if elem[e] + elem[e] = d.__send__(e) + end + elem[:wnum1] ||= 0 + elem[:wday] ||= 0 + end + end + + if g && g[0] == :time + if self <= DateTime + d ||= Date.today + elem[:jd] ||= d.jd + end + end + + elem[:hour] ||= 0 + elem[:min] ||= 0 + elem[:sec] ||= 0 + elem[:sec] = [elem[:sec], 59].min + + elem + end + + private_class_method :complete_frags + + def self.valid_date_frags?(elem, sg) # :nodoc: + catch :jd do + a = elem.values_at(:jd) + if a.all? + if jd = valid_jd?(*(a << sg)) + throw :jd, jd + end + end + + a = elem.values_at(:year, :yday) + if a.all? + if jd = valid_ordinal?(*(a << sg)) + throw :jd, jd + end + end + + a = elem.values_at(:year, :mon, :mday) + if a.all? + if jd = valid_civil?(*(a << sg)) + throw :jd, jd + end + end + + a = elem.values_at(:cwyear, :cweek, :cwday) + if a[2].nil? && elem[:wday] + a[2] = elem[:wday].nonzero? || 7 + end + if a.all? + if jd = valid_commercial?(*(a << sg)) + throw :jd, jd + end + end + + a = elem.values_at(:year, :wnum0, :wday) + if a[2].nil? && elem[:cwday] + a[2] = elem[:cwday] % 7 + end + if a.all? + if jd = valid_weeknum?(*(a << 0 << sg)) + throw :jd, jd + end + end + + a = elem.values_at(:year, :wnum1, :wday) + if a[2] + a[2] = (a[2] - 1) % 7 + end + if a[2].nil? && elem[:cwday] + a[2] = (elem[:cwday] - 1) % 7 + end + if a.all? + if jd = valid_weeknum?(*(a << 1 << sg)) + throw :jd, jd + end + end + end + end + + private_class_method :valid_date_frags? + + def self.valid_time_frags? (elem) # :nodoc: + h, min, s = elem.values_at(:hour, :min, :sec) + valid_time?(h, min, s) + end + + private_class_method :valid_time_frags? + + def self.new_by_frags(elem, sg) # :nodoc: + elem = rewrite_frags(elem) + elem = complete_frags(elem) + unless jd = valid_date_frags?(elem, sg) + raise ArgumentError, 'invalid date' + end + new!(jd_to_ajd(jd, 0, 0), 0, sg) + end + + private_class_method :new_by_frags + + # Create a new Date object by parsing from a String + # according to a specified format. + # + # +str+ is a String holding a date representation. + # +fmt+ is the format that the date is in. See + # date/format.rb for details on supported formats. + # + # The default +str+ is '-4712-01-01', and the default + # +fmt+ is '%F', which means Year-Month-Day_of_Month. + # This gives Julian Day Number day 0. + # + # +sg+ specifies the Day of Calendar Reform. + # + # An ArgumentError will be raised if +str+ cannot be + # parsed. + def self.strptime(str='-4712-01-01', fmt='%F', sg=ITALY) + elem = _strptime(str, fmt) + new_by_frags(elem, sg) + end + + # Create a new Date object by parsing from a String, + # without specifying the format. + # + # +str+ is a String holding a date representation. + # +comp+ specifies whether to interpret 2-digit years + # as 19XX (>= 69) or 20XX (< 69); the default is not to. + # The method will attempt to parse a date from the String + # using various heuristics; see #_parse in date/format.rb + # for more details. If parsing fails, an ArgumentError + # will be raised. + # + # The default +str+ is '-4712-01-01'; this is Julian + # Day Number day 0. + # + # +sg+ specifies the Day of Calendar Reform. + def self.parse(str='-4712-01-01', comp=false, sg=ITALY) + elem = _parse(str, comp) + new_by_frags(elem, sg) + end + + class << self + + def once(*ids) # :nodoc: + for id in ids + module_eval <<-"end;" + alias_method :__#{id.to_i}__, :#{id.to_s} + private :__#{id.to_i}__ + def #{id.to_s}(*args, &block) + (@__#{id.to_i}__ ||= [__#{id.to_i}__(*args, &block)])[0] + end + end; + end + end + + private :once + + end + + # *NOTE* this is the documentation for the method new!(). If + # you are reading this as the documentation for new(), that is + # because rdoc doesn't fully support the aliasing of the + # initialize() method. + # new() is in + # fact an alias for #civil(): read the documentation for that + # method instead. + # + # Create a new Date object. + # + # +ajd+ is the Astronomical Julian Day Number. + # +of+ is the offset from UTC as a fraction of a day. + # Both default to 0. + # + # +sg+ specifies the Day of Calendar Reform to use for this + # Date object. + # + # Using one of the factory methods such as Date::civil is + # generally easier and safer. + def initialize(ajd=0, of=0, sg=ITALY) @ajd, @of, @sg = ajd, of, sg end + + # Get the date as an Astronomical Julian Day Number. + def ajd() @ajd end + + # Get the date as an Astronomical Modified Julian Day Number. + def amjd() self.class.ajd_to_amjd(@ajd) end + + once :amjd + + # Get the date as a Julian Day Number. + def jd() self.class.ajd_to_jd(@ajd, @of)[0] end + + # Get any fractional day part of the date. + def day_fraction() self.class.ajd_to_jd(@ajd, @of)[1] end + + # Get the date as a Modified Julian Day Number. + def mjd() self.class.jd_to_mjd(jd) end + + # Get the date as the number of days since the Day of Calendar + # Reform (in Italy and the Catholic countries). + def ld() self.class.jd_to_ld(jd) end + + once :jd, :day_fraction, :mjd, :ld + + # Get the date as a Civil Date, [year, month, day_of_month] + def civil() self.class.jd_to_civil(jd, @sg) end # :nodoc: + + # Get the date as an Ordinal Date, [year, day_of_year] + def ordinal() self.class.jd_to_ordinal(jd, @sg) end # :nodoc: + + # Get the date as a Commercial Date, [year, week_of_year, day_of_week] + def commercial() self.class.jd_to_commercial(jd, @sg) end # :nodoc: + + def weeknum0() self.class.__send__(:jd_to_weeknum, jd, 0, @sg) end # :nodoc: + def weeknum1() self.class.__send__(:jd_to_weeknum, jd, 1, @sg) end # :nodoc: + + once :civil, :ordinal, :commercial, :weeknum0, :weeknum1 + private :civil, :ordinal, :commercial, :weeknum0, :weeknum1 + + # Get the year of this date. + def year() civil[0] end + + # Get the day-of-the-year of this date. + # + # January 1 is day-of-the-year 1 + def yday() ordinal[1] end + + # Get the month of this date. + # + # January is month 1. + def mon() civil[1] end + + # Get the day-of-the-month of this date. + def mday() civil[2] end + + alias_method :month, :mon + alias_method :day, :mday + + def wnum0() weeknum0[1] end # :nodoc: + def wnum1() weeknum1[1] end # :nodoc: + + private :wnum0, :wnum1 + + # Get the time of this date as [hours, minutes, seconds, + # fraction_of_a_second] + def time() self.class.day_fraction_to_time(day_fraction) end # :nodoc: + + once :time + private :time + + # Get the hour of this date. + def hour() time[0] end + + # Get the minute of this date. + def min() time[1] end + + # Get the second of this date. + def sec() time[2] end + + # Get the fraction-of-a-second of this date. The unit is in days. + # I do NOT recommend you to use this method. + def sec_fraction() time[3] end + + private :hour, :min, :sec, :sec_fraction + + def zone() strftime('%:z') end + + private :zone + + # Get the commercial year of this date. See *Commercial* *Date* + # in the introduction for how this differs from the normal year. + def cwyear() commercial[0] end + + # Get the commercial week of the year of this date. + def cweek() commercial[1] end + + # Get the commercial day of the week of this date. Monday is + # commercial day-of-week 1; Sunday is commercial day-of-week 7. + def cwday() commercial[2] end + + # Get the week day of this date. Sunday is day-of-week 0; + # Saturday is day-of-week 6. + def wday() self.class.jd_to_wday(jd) end + + once :wday + +=begin + MONTHNAMES.each_with_index do |n, i| + if n + define_method(n.downcase + '?'){mon == i} + end + end + + DAYNAMES.each_with_index do |n, i| + define_method(n.downcase + '?'){wday == i} + end +=end + + # Is the current date old-style (Julian Calendar)? + def julian? () self.class.julian?(jd, @sg) end + + # Is the current date new-style (Gregorian Calendar)? + def gregorian? () self.class.gregorian?(jd, @sg) end + + once :julian?, :gregorian? + + def fix_style # :nodoc: + if julian? + then self.class::JULIAN + else self.class::GREGORIAN end + end + + private :fix_style + + # Is this a leap year? + def leap? + self.class.jd_to_civil(self.class.civil_to_jd(year, 3, 1, fix_style) - 1, + fix_style)[-1] == 29 + end + + once :leap? + + # When is the Day of Calendar Reform for this Date object? + def start() @sg end + + # Create a copy of this Date object using a new Day of Calendar Reform. + def new_start(sg=self.class::ITALY) self.class.new!(@ajd, @of, sg) end + + # Create a copy of this Date object that uses the Italian/Catholic + # Day of Calendar Reform. + def italy() new_start(self.class::ITALY) end + + # Create a copy of this Date object that uses the English/Colonial + # Day of Calendar Reform. + def england() new_start(self.class::ENGLAND) end + + # Create a copy of this Date object that always uses the Julian + # Calendar. + def julian() new_start(self.class::JULIAN) end + + # Create a copy of this Date object that always uses the Gregorian + # Calendar. + def gregorian() new_start(self.class::GREGORIAN) end + + def offset() @of end + + def new_offset(of=0) + if String === of + of = (self.class.zone_to_diff(of) || 0).to_r/86400 + end + self.class.new!(@ajd, of, @sg) + end + + private :offset, :new_offset + + # Return a new Date object that is +n+ days later than the + # current one. + # + # +n+ may be a negative value, in which case the new Date + # is earlier than the current one; however, #-() might be + # more intuitive. + # + # If +n+ is not a Numeric, a TypeError will be thrown. In + # particular, two Dates cannot be added to each other. + def + (n) + case n + when Numeric; return self.class.new!(@ajd + n, @of, @sg) + end + raise TypeError, 'expected numeric' + end + + # If +x+ is a Numeric value, create a new Date object that is + # +x+ days earlier than the current one. + # + # If +x+ is a Date, return the number of days between the + # two dates; or, more precisely, how many days later the current + # date is than +x+. + # + # If +x+ is neither Numeric nor a Date, a TypeError is raised. + def - (x) + case x + when Numeric; return self.class.new!(@ajd - x, @of, @sg) + when Date; return @ajd - x.ajd + end + raise TypeError, 'expected numeric or date' + end + + # Compare this date with another date. + # + # +other+ can also be a Numeric value, in which case it is + # interpreted as an Astronomical Julian Day Number. + # + # Comparison is by Astronomical Julian Day Number, including + # fractional days. This means that both the time and the + # timezone offset are taken into account when comparing + # two DateTime instances. When comparing a DateTime instance + # with a Date instance, the time of the latter will be + # considered as falling on midnight UTC. + def <=> (other) + case other + when Numeric; return @ajd <=> other + when Date; return @ajd <=> other.ajd + end + nil + end + + # The relationship operator for Date. + # + # Compares dates by Julian Day Number. When comparing + # two DateTime instances, or a DateTime with a Date, + # the instances will be regarded as equivalent if they + # fall on the same date in local time. + def === (other) + case other + when Numeric; return jd == other + when Date; return jd == other.jd + end + false + end + + def next_day(n=1) self + n end +# def prev_day(n=1) self - n end + + private :next_day + + # Return a new Date one day after this one. + def next() next_day end + + alias_method :succ, :next + + # Return a new Date object that is +n+ months later than + # the current one. + # + # If the day-of-the-month of the current Date is greater + # than the last day of the target month, the day-of-the-month + # of the returned Date will be the last day of the target month. + def >> (n) + y, m = (year * 12 + (mon - 1) + n).divmod(12) + m, = (m + 1) .divmod(1) + d = mday + d -= 1 until jd2 = self.class.valid_civil?(y, m, d, fix_style) + self + (jd2 - jd) + end + + # Return a new Date object that is +n+ months earlier than + # the current one. + # + # If the day-of-the-month of the current Date is greater + # than the last day of the target month, the day-of-the-month + # of the returned Date will be the last day of the target month. + def << (n) self >> -n end + +=begin + def next_month(n=1) self >> n end + def prev_month(n=1) self << n end + + def next_year(n=1) self >> n * 12 end + def prev_year(n=1) self << n * 12 end +=end + +# require 'enumerator' + + # Step the current date forward +step+ days at a + # time (or backward, if +step+ is negative) until + # we reach +limit+ (inclusive), yielding the resultant + # date at each step. + def step(limit, step=1) # :yield: date +=begin + unless block_given? + return to_enum(:step, limit, step) + end +=end + da = self + op = %w(- <= >=)[step <=> 0] + while da.__send__(op, limit) + yield da + da += step + end + self + end + + # Step forward one day at a time until we reach +max+ + # (inclusive), yielding each date as we go. + def upto(max, &block) # :yield: date + step(max, +1, &block) + end + + # Step backward one day at a time until we reach +min+ + # (inclusive), yielding each date as we go. + def downto(min, &block) # :yield: date + step(min, -1, &block) + end + + # Is this Date equal to +other+? + # + # +other+ must both be a Date object, and represent the same date. + def eql? (other) Date === other && self == other end + + # Calculate a hash value for this date. + def hash() @ajd.hash end + + # Return internal object state as a programmer-readable string. + def inspect() format('#<%s: %s,%s,%s>', self.class, @ajd, @of, @sg) end + + # Return the date as a human-readable string. + # + # The format used is YYYY-MM-DD. + def to_s() strftime end + + # Dump to Marshal format. + def _dump(limit) Marshal.dump([@ajd, @of, @sg], -1) end + +# def self._load(str) new!(*Marshal.load(str)) end + + # Load from Marshall format. + def self._load(str) + a = Marshal.load(str) + if a.size == 2 + ajd, sg = a + of = 0 + ajd -= 1.to_r/2 + else + ajd, of, sg = a + end + new!(ajd, of, sg) + end + +end + +# Class representing a date and time. +# +# See the documentation to the file date.rb for an overview. +# +# DateTime objects are immutable once created. +# +# == Other methods. +# +# The following methods are defined in Date, but declared private +# there. They are made public in DateTime. They are documented +# here. +# +# === hour() +# +# Get the hour-of-the-day of the time. This is given +# using the 24-hour clock, counting from midnight. The first +# hour after midnight is hour 0; the last hour of the day is +# hour 23. +# +# === min() +# +# Get the minute-of-the-hour of the time. +# +# === sec() +# +# Get the second-of-the-minute of the time. +# +# === sec_fraction() +# +# Get the fraction of a second of the time. This is returned as +# a +Rational+. The unit is in days. +# I do NOT recommend you to use this method. +# +# === zone() +# +# Get the time zone as a String. This is representation of the +# time offset such as "+1000", not the true time-zone name. +# +# === offset() +# +# Get the time zone offset as a fraction of a day. This is returned +# as a +Rational+. +# +# === new_offset(of=0) +# +# Create a new DateTime object, identical to the current one, except +# with a new time zone offset of +of+. +of+ is the new offset from +# UTC as a fraction of a day. +# +class DateTime < Date + + # Create a new DateTime object corresponding to the specified + # Julian Day Number +jd+ and hour +h+, minute +min+, second +s+. + # + # The 24-hour clock is used. Negative values of +h+, +min+, and + # +sec+ are treating as counting backwards from the end of the + # next larger unit (e.g. a +min+ of -2 is treated as 58). No + # wraparound is performed. If an invalid time portion is specified, + # an ArgumentError is raised. + # + # +of+ is the offset from UTC as a fraction of a day (defaults to 0). + # +sg+ specifies the Day of Calendar Reform. + # + # All day/time values default to 0. + def self.jd(jd=0, h=0, min=0, s=0, of=0, sg=ITALY) + unless (jd = valid_jd?(jd, sg)) && + (fr = valid_time?(h, min, s)) + raise ArgumentError, 'invalid date' + end + if String === of + of = (zone_to_diff(of) || 0).to_r/86400 + end + new!(jd_to_ajd(jd, fr, of), of, sg) + end + + # Create a new DateTime object corresponding to the specified + # Ordinal Date and hour +h+, minute +min+, second +s+. + # + # The 24-hour clock is used. Negative values of +h+, +min+, and + # +sec+ are treating as counting backwards from the end of the + # next larger unit (e.g. a +min+ of -2 is treated as 58). No + # wraparound is performed. If an invalid time portion is specified, + # an ArgumentError is raised. + # + # +of+ is the offset from UTC as a fraction of a day (defaults to 0). + # +sg+ specifies the Day of Calendar Reform. + # + # +y+ defaults to -4712, and +d+ to 1; this is Julian Day Number + # day 0. The time values default to 0. + def self.ordinal(y=-4712, d=1, h=0, min=0, s=0, of=0, sg=ITALY) + unless (jd = valid_ordinal?(y, d, sg)) && + (fr = valid_time?(h, min, s)) + raise ArgumentError, 'invalid date' + end + if String === of + of = (zone_to_diff(of) || 0).to_r/86400 + end + new!(jd_to_ajd(jd, fr, of), of, sg) + end + + # Create a new DateTime object corresponding to the specified + # Civil Date and hour +h+, minute +min+, second +s+. + # + # The 24-hour clock is used. Negative values of +h+, +min+, and + # +sec+ are treating as counting backwards from the end of the + # next larger unit (e.g. a +min+ of -2 is treated as 58). No + # wraparound is performed. If an invalid time portion is specified, + # an ArgumentError is raised. + # + # +of+ is the offset from UTC as a fraction of a day (defaults to 0). + # +sg+ specifies the Day of Calendar Reform. + # + # +y+ defaults to -4712, +m+ to 1, and +d+ to 1; this is Julian Day + # Number day 0. The time values default to 0. + def self.civil(y=-4712, m=1, d=1, h=0, min=0, s=0, of=0, sg=ITALY) + unless (jd = valid_civil?(y, m, d, sg)) && + (fr = valid_time?(h, min, s)) + raise ArgumentError, 'invalid date' + end + if String === of + of = (zone_to_diff(of) || 0).to_r/86400 + end + new!(jd_to_ajd(jd, fr, of), of, sg) + end + + class << self; alias_method :new, :civil end + + # Create a new DateTime object corresponding to the specified + # Commercial Date and hour +h+, minute +min+, second +s+. + # + # The 24-hour clock is used. Negative values of +h+, +min+, and + # +sec+ are treating as counting backwards from the end of the + # next larger unit (e.g. a +min+ of -2 is treated as 58). No + # wraparound is performed. If an invalid time portion is specified, + # an ArgumentError is raised. + # + # +of+ is the offset from UTC as a fraction of a day (defaults to 0). + # +sg+ specifies the Day of Calendar Reform. + # + # +y+ defaults to 1582, +w+ to 41, and +d+ to 5; this is the Day of + # Calendar Reform for Italy and the Catholic countries. + # The time values default to 0. + def self.commercial(y=1582, w=41, d=5, h=0, min=0, s=0, of=0, sg=ITALY) + unless (jd = valid_commercial?(y, w, d, sg)) && + (fr = valid_time?(h, min, s)) + raise ArgumentError, 'invalid date' + end + if String === of + of = (zone_to_diff(of) || 0).to_r/86400 + end + new!(jd_to_ajd(jd, fr, of), of, sg) + end + + def self.weeknum(y=1582, w=41, d=5, f=0, h=0, min=0, s=0, of=0, sg=ITALY) # :nodoc: + unless (jd = valid_weeknum?(y, w, d, f, sg)) && + (fr = valid_time?(h, min, s)) + raise ArgumentError, 'invalid date' + end + if String === of + of = (zone_to_diff(of) || 0).to_r/86400 + end + new!(jd_to_ajd(jd, fr, of), of, sg) + end + + private_class_method :weeknum + + def self.new_by_frags(elem, sg) # :nodoc: + elem = rewrite_frags(elem) + elem = complete_frags(elem) + unless (jd = valid_date_frags?(elem, sg)) && + (fr = valid_time_frags?(elem)) + raise ArgumentError, 'invalid date' + end + sf = (elem[:sec_fraction] || 0) + fr += sf/86400 + of = (elem[:offset] || 0) + of = of.to_r/86400 + new!(jd_to_ajd(jd, fr, of), of, sg) + end + + private_class_method :new_by_frags + + # Create a new DateTime object by parsing from a String + # according to a specified format. + # + # +str+ is a String holding a date-time representation. + # +fmt+ is the format that the date-time is in. See + # date/format.rb for details on supported formats. + # + # The default +str+ is '-4712-01-01T00:00:00+00:00', and the default + # +fmt+ is '%FT%T%z'. This gives midnight on Julian Day Number day 0. + # + # +sg+ specifies the Day of Calendar Reform. + # + # An ArgumentError will be raised if +str+ cannot be + # parsed. + def self.strptime(str='-4712-01-01T00:00:00+00:00', fmt='%FT%T%z', sg=ITALY) + elem = _strptime(str, fmt) + new_by_frags(elem, sg) + end + + # Create a new DateTime object by parsing from a String, + # without specifying the format. + # + # +str+ is a String holding a date-time representation. + # +comp+ specifies whether to interpret 2-digit years + # as 19XX (>= 69) or 20XX (< 69); the default is not to. + # The method will attempt to parse a date-time from the String + # using various heuristics; see #_parse in date/format.rb + # for more details. If parsing fails, an ArgumentError + # will be raised. + # + # The default +str+ is '-4712-01-01T00:00:00+00:00'; this is Julian + # Day Number day 0. + # + # +sg+ specifies the Day of Calendar Reform. + def self.parse(str='-4712-01-01T00:00:00+00:00', comp=false, sg=ITALY) + elem = _parse(str, comp) + new_by_frags(elem, sg) + end + + public :hour, :min, :sec, :sec_fraction, :zone, :offset, :new_offset + +end + +class Time + +# def to_time() getlocal end + + def to_date + jd = Date.civil_to_jd(year, mon, mday, Date::ITALY) + Date.new!(Date.jd_to_ajd(jd, 0, 0), 0, Date::ITALY) + end + + def to_datetime + jd = DateTime.civil_to_jd(year, mon, mday, DateTime::ITALY) + fr = DateTime.time_to_day_fraction(hour, min, [sec, 59].min) + + usec.to_r/86400000000 + of = utc_offset.to_r/86400 + DateTime.new!(DateTime.jd_to_ajd(jd, fr, of), of, DateTime::ITALY) + end + + private :to_date, :to_datetime + +end + +class Date + +=begin + def to_time() Time.local(year, mon, mday) end + def to_date() self end + def to_datetime() DateTime.new!(self.class.jd_to_ajd(jd, 0, 0), @of, @sg) end +=end + + # Create a new Date object representing today. + # + # +sg+ specifies the Day of Calendar Reform. + def self.today(sg=ITALY) Time.now.__send__(:to_date) .new_start(sg) end + + # Create a new DateTime object representing the current time. + # + # +sg+ specifies the Day of Calendar Reform. + def self.now (sg=ITALY) Time.now.__send__(:to_datetime).new_start(sg) end + + private_class_method :now + +end + +class DateTime < Date + +=begin + def to_time + d = new_offset(0) + d.instance_eval do + Time.utc(year, mon, mday, hour, min, sec, + (sec_fraction * 86400000000).to_i) + end. + getlocal + end + + def to_date() Date.new!(self.class.jd_to_ajd(jd, 0, 0), 0, @sg) end + def to_datetime() self end +=end + + private_class_method :today + public_class_method :now + +end + +class Date + + [ %w(os? julian?), + %w(ns? gregorian?), + %w(exist1? valid_jd?), + %w(exist2? valid_ordinal?), + %w(exist3? valid_date?), + %w(exist? valid_date?), + %w(existw? valid_commercial?), + %w(new0 new!), + %w(new1 jd), + %w(new2 ordinal), + %w(new3 new), + %w(neww commercial) + ].each do |old, new| + module_eval <<-"end;" + def self.#{old}(*args, &block) + if $VERBOSE + warn("\#{caller.shift.sub(/:in .*/, '')}: " \ + "warning: \#{self}::#{old} is deprecated; " \ + "use \#{self}::#{new}") + end + #{new}(*args, &block) + end + end; + end + + [ %w(os? julian?), + %w(ns? gregorian?), + %w(sg start), + %w(newsg new_start), + %w(of offset), + %w(newof new_offset) + ].each do |old, new| + module_eval <<-"end;" + def #{old}(*args, &block) + if $VERBOSE + warn("\#{caller.shift.sub(/:in .*/, '')}: " \ + "warning: \#{self.class}\##{old} is deprecated; " \ + "use \#{self.class}\##{new}") + end + #{new}(*args, &block) + end + end; + end + + private :of, :newof + +end + +class DateTime < Date + + public :of, :newof + +end |