Class: Date
| Relationships & Source Files | |
| Namespace Children | |
| Classes: | |
| Exceptions: | |
| Extension / Inclusion / Inheritance Descendants | |
| Subclasses: | |
| Super Chains via Extension / Inclusion / Inheritance | |
| Instance Chain: 
          self,
          Comparable
         | |
| Inherits: | Object | 
| Defined in: | ext/date/date_core.c, ext/date/lib/date.rb | 
Overview
Class Date provides methods for storing and manipulating calendar dates.
Consider using class Time instead of class Date if:
- 
You need both dates and times; Date handles only dates. 
- 
You need only Gregorian dates (and not Julian dates); see Julian and Gregorian Calendars. 
A Date object, once created, is immutable, and cannot be modified.
Creating a Date
You can create a date for the current date, using .today:
Date.today # => #<Date: 1999-12-31>You can create a specific date from various combinations of arguments:
- 
.new takes integer year, month, and day-of-month: Date.new(1999, 12, 31) # => #<Date: 1999-12-31>
- 
.ordinal takes integer year and day-of-year: Date.ordinal(1999, 365) # => #<Date: 1999-12-31>
- 
.jd takes integer Julian day: Date.jd(2451544) # => #<Date: 1999-12-31>
- 
.commercial takes integer commercial data (year, week, day-of-week): Date.commercial(1999, 52, 5) # => #<Date: 1999-12-31>
- 
.parse takes a string, which it parses heuristically: Date.parse('1999-12-31') # => #<Date: 1999-12-31> Date.parse('31-12-1999') # => #<Date: 1999-12-31> Date.parse('1999-365') # => #<Date: 1999-12-31> Date.parse('1999-W52-5') # => #<Date: 1999-12-31>
- 
.strptime takes a date string and a format string, then parses the date string according to the format string: Date.strptime('1999-12-31', '%Y-%m-%d') # => #<Date: 1999-12-31> Date.strptime('31-12-1999', '%d-%m-%Y') # => #<Date: 1999-12-31> Date.strptime('1999-365', '%Y-%j') # => #<Date: 1999-12-31> Date.strptime('1999-W52-5', '%G-W%V-%u') # => #<Date: 1999-12-31> Date.strptime('1999 52 5', '%Y %U %w') # => #<Date: 1999-12-31> Date.strptime('1999 52 5', '%Y %W %u') # => #<Date: 1999-12-31> Date.strptime('fri31dec99', '%a%d%b%y') # => #<Date: 1999-12-31>
See also the specialized methods in “Specialized Format Strings” in Formats for s and Times
Argument limit
Certain singleton methods in Date that parse string arguments also take optional keyword argument limit, which can limit the length of the string argument.
When limit is:
- 
Non-negative: raises ArgumentError if the string length is greater than limit. 
- 
Other numeric or nil: ignoreslimit.
- 
Other non-numeric: raises TypeError. 
Constant Summary
- 
    ABBR_DAYNAMES =
    # File 'ext/date/date_core.c', line 9625An array of strings of abbreviated day names in English. The first is “Sun”. mk_ary_of_str(7, abbr_daynames) 
- 
    ABBR_MONTHNAMES =
    # File 'ext/date/date_core.c', line 9614An array of strings of abbreviated month names in English. The first element is nil. mk_ary_of_str(13, abbr_monthnames) 
- 
    DAYNAMES =
    # File 'ext/date/date_core.c', line 9620An array of strings of the full names of days of the week in English. The first is “Sunday”. mk_ary_of_str(7, daynames) 
- 
    ENGLAND =
    # File 'ext/date/date_core.c', line 9635The Julian day number of the day of calendar reform for England and her colonies. INT2FIX(ENGLAND) 
- 
    GREGORIAN =
    # File 'ext/date/date_core.c', line 9645The Julian day number of the day of calendar reform for the proleptic Gregorian calendar. DBL2NUM(GREGORIAN) 
- 
    ITALY =
    # File 'ext/date/date_core.c', line 9630The Julian day number of the day of calendar reform for Italy and some catholic countries. INT2FIX(ITALY) 
- 
    JULIAN =
    # File 'ext/date/date_core.c', line 9640The Julian day number of the day of calendar reform for the proleptic Julian calendar. DBL2NUM(JULIAN) 
- 
    MONTHNAMES =
    # File 'ext/date/date_core.c', line 9609An array of strings of full month names in English. The first element is nil. mk_ary_of_str(13, monthnames) 
- 
    VERSION =
    Internal use only
    
 # File 'ext/date/lib/date.rb', line 7"3.4.1"
Class Method Summary
- 
    
      ._httpdate(string, limit: 128)  ⇒ Hash 
    
    Returns a hash of values parsed from string, which should be a valid HTTP date format:
- 
    
      ._iso8601(string, limit: 128)  ⇒ Hash 
    
    Returns a hash of values parsed from string, which should contain an ISO 8601 formatted date:
- 
    
      ._jisx0301(string, limit: 128)  ⇒ Hash 
    
    Returns a hash of values parsed from string, which should be a valid JIS X 0301 date format:
- 
    
      ._parse(string, comp = true, limit: 128)  ⇒ Hash 
    
    Note: This method recognizes many forms in string, but it is not a validator.
- 
    
      ._rfc2822(string, limit: 128)  ⇒ Hash 
    
    Alias for ._rfc822. 
- 
    
      ._rfc3339(string, limit: 128)  ⇒ Hash 
    
    Returns a hash of values parsed from string, which should be a valid RFC 3339 format:
- 
    
      ._rfc822(string, limit: 128)  ⇒ Hash 
      (also: ._rfc2822)
    
    Returns a hash of values parsed from string, which should be a valid RFC 2822 date format:
- 
    
      ._strptime(string, format = '%F')  ⇒ Hash 
    
    Returns a hash of values parsed from stringaccording to the givenformat:
- 
    
      ._xmlschema(string, limit: 128)  ⇒ Hash 
    
    Returns a hash of values parsed from string, which should be a valid XML date format:
- 
    
      .civil(*args)  
    
    Same as .new. 
- 
    
      .commercial(cwyear = -4712, cweek = 1, cwday = 1, start = Date::ITALY)  ⇒ Date 
    
    Returns a new Date object constructed from the arguments. 
- 
    
      .gregorian_leap?(year)  ⇒ Boolean 
    
    Alias for .leap?. 
- 
    
      .httpdate(string = 'Mon, 01 Jan -4712 00:00:00 GMT', start = Date::ITALY, limit: 128)  ⇒ Date 
    
    Returns a new Date object with values parsed from string, which should be a valid HTTP date format:
- 
    
      .iso8601(string = '-4712-01-01', start = Date::ITALY, limit: 128)  ⇒ Date 
    
    Returns a new Date object with values parsed from string, which should contain an ISO 8601 formatted date:
- 
    
      .jd(jd = 0, start = Date::ITALY)  ⇒ Date 
    
    Returns a new Date object formed from the arguments: 
- 
    
      .jisx0301(string = '-4712-01-01', start = Date::ITALY, limit: 128)  ⇒ Date 
    
    Returns a new Date object with values parsed from string, which should be a valid JIS X 0301 format:
- 
    
      .julian_leap?(year)  ⇒ Boolean 
    
    Returns trueif the given year is a leap year in the proleptic Julian calendar,falseotherwise:
- 
    
      .leap?(year)  ⇒ Boolean 
      (also: .gregorian_leap?)
    
    Returns trueif the given year is a leap year in the proleptic Gregorian calendar,falseotherwise:
- 
    
      .new(year = -4712, month = 1, mday = 1, start = Date::ITALY)  ⇒ Date 
    
    constructor
    Returns a new Date object constructed from the given arguments: 
- 
    
      .ordinal(year = -4712, yday = 1, start = Date::ITALY)  ⇒ Date 
    
    Returns a new Date object formed fom the arguments. 
- 
    
      .parse(string = '-4712-01-01', comp = true, start = Date::ITALY, limit: 128)  ⇒ Date 
    
    Note: This method recognizes many forms in string, but it is not a validator.
- 
    
      .rfc2822(string = 'Mon, 1 Jan -4712 00:00:00 +0000', start = Date::ITALY, limit: 128)  ⇒ Date 
    
    Alias for .rfc822. 
- 
    
      .rfc3339(string = '-4712-01-01T00:00:00+00:00', start = Date::ITALY, limit: 128)  ⇒ Date 
    
    Returns a new Date object with values parsed from string, which should be a valid RFC 3339 format:
- 
    
      .rfc822(string = 'Mon, 1 Jan -4712 00:00:00 +0000', start = Date::ITALY, limit: 128)  ⇒ Date 
      (also: .rfc2822)
    
    Returns a new Date object with values parsed from string, which should be a valid RFC 2822 date format:
- 
    
      .strptime(string = '-4712-01-01', format = '%F', start = Date::ITALY)  ⇒ Date 
    
    Returns a new Date object with values parsed from string, according to the givenformat:
- 
    
      .today(start = Date::ITALY)  ⇒ Date 
    
    Returns a new Date object constructed from the present date: 
- 
    
      .valid_civil?(year, month, mday, start = Date::ITALY)  ⇒ Boolean 
    
    Alias for .valid_date?. 
- 
    
      .valid_commercial?(cwyear, cweek, cwday, start = Date::ITALY)  ⇒ Boolean 
    
    Returns trueif the arguments define a valid commercial date,falseotherwise:
- 
    
      .valid_date?(year, month, mday, start = Date::ITALY)  ⇒ Boolean 
      (also: .valid_civil?)
    
    Returns trueif the arguments define a valid ordinal date,falseotherwise:
- 
    
      .valid_jd?(jd, start = Date::ITALY)  ⇒ true 
    
    Implemented for compatibility; returns trueunless .jd is invalid (i.e., not a Numeric).
- 
    
      .valid_ordinal?(year, yday, start = Date::ITALY)  ⇒ Boolean 
    
    Returns trueif the arguments define a valid ordinal date,falseotherwise:
- 
    
      .xmlschema(string = '-4712-01-01', start = Date::ITALY, limit: 128)  ⇒ Date 
    
    Returns a new Date object with values parsed from string, which should be a valid XML date format:
- ._load(s) Internal use only
- .new!(*args) Internal use only
- .nth_kday(*args) Internal use only
- .test_all Internal use only
- .test_civil Internal use only
- .test_commercial Internal use only
- .test_nth_kday Internal use only
- .test_ordinal Internal use only
- .test_unit_conv Internal use only
- .test_weeknum Internal use only
- .weeknum(*args) Internal use only
Instance Attribute Summary
- 
    
      #friday?  ⇒ Boolean 
    
    readonly
    Returns trueifselfis a Friday,falseotherwise.
- 
    
      #gregorian  ⇒ Date 
    
    readonly
    Equivalent to #new_start with argument GREGORIAN. 
- 
    
      #gregorian?  ⇒ Boolean 
    
    readonly
    Returns trueif the date is on or after the date of calendar reform,falseotherwise:
- 
    
      #infinite?  ⇒ Boolean 
    
    readonly
    Returns false
- 
    
      #julian  ⇒ Date 
    
    readonly
    Equivalent to #new_start with argument JULIAN. 
- 
    
      #julian?  ⇒ Boolean 
    
    readonly
    Returns trueif the date is before the date of calendar reform,falseotherwise:
- 
    
      #leap?  ⇒ Boolean 
    
    readonly
    Returns trueif the year is a leap year,falseotherwise:
- 
    
      #monday?  ⇒ Boolean 
    
    readonly
    Returns trueifselfis a Monday,falseotherwise.
- 
    
      #saturday?  ⇒ Boolean 
    
    readonly
    Returns trueifselfis a Saturday,falseotherwise.
- 
    
      #sunday?  ⇒ Boolean 
    
    readonly
    Returns trueifselfis a Sunday,falseotherwise.
- 
    
      #thursday?  ⇒ Boolean 
    
    readonly
    Returns trueifselfis a Thursday,falseotherwise.
- 
    
      #tuesday?  ⇒ Boolean 
    
    readonly
    Returns trueifselfis a Tuesday,falseotherwise.
- 
    
      #wednesday?  ⇒ Boolean 
    
    readonly
    Returns trueifselfis a Wednesday,falseotherwise.
Instance Method Summary
- 
    
      #+(other)  ⇒ Date 
    
    Returns a date object pointing otherdays after self.
- 
    
      #-(other)  ⇒ Date, Rational 
    
    If the other is a date object, returns a Rational whose value is the difference between the two dates in days. 
- 
    
      #<<(n)  ⇒ Date 
    
    Returns a new Date object representing the date nmonths earlier;nshould be a numeric:
- 
    
      #<=>(other)  ⇒ 1, ... 
    
    Compares selfandother, returning:
- 
    
      #===(other)  ⇒ true, ... 
    
    Returns trueifselfandotherrepresent the same date,falseif not,nilif the two are not comparable.
- 
    
      #>>(n)  ⇒ Date 
    
    Returns a new Date object representing the date nmonths later;nshould be a numeric:
- 
    
      #ajd  ⇒ Rational 
    
    Returns the astronomical Julian day number. 
- 
    
      #amjd  ⇒ Rational 
    
    Returns the astronomical modified Julian day number. 
- 
    
      #asctime  ⇒ String 
    
    Alias for #ctime. 
- 
    
      #ctime  ⇒ String 
      (also: #asctime)
    
    Equivalent to #strftime with argument '%a %b %e %T %Y'(or its shorthand form'%c'):
- 
    
      #cwday  ⇒ Integer 
    
    Returns the commercial-date weekday index for self(see .commercial); 1 is Monday:
- 
    
      #cweek  ⇒ Integer 
    
    Returns commercial-date week index for self(see .commercial):
- 
    
      #cwyear  ⇒ Integer 
    
    Returns commercial-date year for self(see .commercial):
- 
    
      #day  ⇒ Integer 
      (also: #mday)
    
    Returns the day of the month in range (1..31): 
- 
    
      #day_fraction  ⇒ Rational 
    
    Returns the fractional part of the day in range (Rational(0, 1)…Rational(1, 1)): 
- 
    
      #deconstruct_keys(array_of_names_or_nil)  ⇒ Hash 
    
    Returns a hash of the name/value pairs, to use in pattern matching. 
- #downto(min) {|date| ... } ⇒ self
- 
    
      #england  ⇒ Date 
    
    Equivalent to #new_start with argument ENGLAND. 
- 
    
      #httpdate  ⇒ String 
    
    Equivalent to #strftime with argument '%a, %d %b %Y %T GMT'; see Formats for Dates and Times:
- 
    
      #inspect  ⇒ String 
    
    Returns a string representation of self:
- 
    
      #iso8601  ⇒ String 
      (also: #xmlschema)
    
    Equivalent to #strftime with argument '%Y-%m-%d'(or its shorthand form'%F');.
- 
    
      #italy  ⇒ Date 
    
    Equivalent to #new_start with argument ITALY. 
- 
    
      #jd  ⇒ Integer 
    
    Returns the Julian day number. 
- 
    
      #jisx0301  ⇒ String 
    
    Returns a string representation of the date in selfin JIS X 0301 format.
- 
    
      #ld  ⇒ Integer 
    
    Returns the Lilian day number, which is the number of days since the beginning of the Gregorian calendar, October 15, 1582. 
- 
    
      #mday  ⇒ Integer 
    
    Alias for #day. 
- 
    
      #mjd  ⇒ Integer 
    
    Returns the modified Julian day number. 
- 
    
      #mon  ⇒ Integer 
      (also: #month)
    
    Returns the month in range (1..12): 
- 
    
      #month  ⇒ Integer 
    
    Alias for #mon. 
- 
    
      #new_start(start = Date::ITALY])  ⇒ Date 
    
    Returns a copy of selfwith the given #start value:
- 
    
      #next  ⇒ Date 
      (also: #succ)
    
    Returns a new Date object representing the following day: 
- 
    
      #next_day(n = 1)  ⇒ Date 
    
    Equivalent to #+ with argument n.
- 
    
      #next_month(n = 1)  ⇒ Date 
    
    Equivalent to #>> with argument n.
- 
    
      #next_year(n = 1)  ⇒ Date 
    
    Equivalent to #>> with argument n * 12.
- 
    
      #prev_day(n = 1)  ⇒ Date 
    
    Equivalent to #- with argument n.
- 
    
      #prev_month(n = 1)  ⇒ Date 
    
    Equivalent to #<< with argument n.
- 
    
      #prev_year(n = 1)  ⇒ Date 
    
    Equivalent to #<< with argument n * 12.
- 
    
      #rfc2822  ⇒ String 
    
    Alias for #rfc822. 
- 
    
      #rfc3339  ⇒ String 
    
    Equivalent to #strftime with argument '%FT%T%:z'; see Formats for Dates and Times:
- 
    
      #rfc822  ⇒ String 
      (also: #rfc2822)
    
    Equivalent to #strftime with argument '%a, %-d %b %Y %T %z'; see Formats for Dates and Times:
- 
    
      #start  ⇒ Float 
    
    Returns the Julian start date for calendar reform; if not an infinity, the returned value is suitable for passing to #jd: 
- 
    
      #step(limit, step = 1) {|date| ... } ⇒ self 
    
    Calls the block with specified dates; returns self.
- 
    
      #strftime(format = '%F')  ⇒ String 
    
    Returns a string representation of the date in self, formatted according the givenformat:
- 
    
      #succ  ⇒ Date 
    
    Alias for #next. 
- 
    
      #to_date  ⇒ self 
    
    Returns self.
- 
    
      #to_datetime  ⇒ Date 
    
    Returns a ::Timewhose value is the same asself:
- 
    
      #to_s  ⇒ String 
    
    Returns a string representation of the date in selfin ISO 8601 extended date format ('%Y-%m-%d'):
- 
    
      #to_time  ⇒ Time 
    
    Returns a new ::Timeobject with the same value asself; ifselfis a Julian date, derives its Gregorian date for conversion to the Time object:
- 
    
      #upto(max) {|date| ... } ⇒ self 
    
    Equivalent to #step with arguments maxand1.
- 
    
      #wday  ⇒ Integer 
    
    Returns the day of week in range (0..6); Sunday is 0: 
- 
    
      #xmlschema  ⇒ String 
    
    Alias for #iso8601. 
- 
    
      #yday  ⇒ Integer 
    
    Returns the day of the year, in range (1..366): 
- 
    
      #year  ⇒ Integer 
    
    Returns the year: 
- #min (also: #hour, #minute, #sec, #second) private
- 
    
      #minute  
    
    private
    Alias for #min. 
- 
    
      #sec  
    
    private
    Alias for #min. 
- 
    
      #second  
    
    private
    Alias for #min. 
- #eql?(other) ⇒ Boolean Internal use only
- #fill Internal use only
- #hash Internal use only
- #initialize_copy(date) Internal use only
- #inspect_raw Internal use only
- #marshal_dump Internal use only
- #marshal_dump_old Internal use only
- #marshal_load(a) Internal use only
- #nth_kday?(n, k) ⇒ Boolean Internal use only
- 
    
      #hour  
    
    private
    Internal use only
    Alias for #min. 
- #wnum0 private Internal use only
- #wnum1 private Internal use only
Constructor Details
    .new(year = -4712, month = 1, mday = 1, start = Date::ITALY)  ⇒ Date   
Returns a new Date object constructed from the given arguments:
Date.new(2022).to_s        # => "2022-01-01"
Date.new(2022, 2).to_s     # => "2022-02-01"
Date.new(2022, 2, 4).to_s  # => "2022-02-04"Argument #month should be in range (1..12) or range (-12..-1); when the argument is negative, counts backward from the end of the year:
Date.new(2022, -11, 4).to_s # => "2022-02-04"Argument #mday should be in range (1..n) or range (-n..-1) where n is the number of days in the month; when the argument is negative, counts backward from the end of the month.
See argument start.
Related: .jd.
# File 'ext/date/date_core.c', line 3499
static VALUE
date_initialize(int argc, VALUE *argv, VALUE self)
{
    VALUE vy, vm, vd, vsg, y, fr, fr2, ret;
    int m, d;
    double sg;
    struct SimpleDateData *dat = rb_check_typeddata(self, &d_lite_type);
    if (!simple_dat_p(dat)) {
	rb_raise(rb_eTypeError, "Date expected");
    }
    rb_scan_args(argc, argv, "04", &vy, &vm, &vd, &vsg);
    y = INT2FIX(-4712);
    m = 1;
    d = 1;
    fr2 = INT2FIX(0);
    sg = DEFAULT_SG;
    switch (argc) {
      case 4:
	val2sg(vsg, sg);
      case 3:
        check_numeric(vd, "day");
	num2int_with_frac(d, positive_inf);
      case 2:
        check_numeric(vm, "month");
	m = NUM2INT(vm);
      case 1:
        check_numeric(vy, "year");
	y = vy;
    }
    if (guess_style(y, sg) < 0) {
	VALUE nth;
	int ry, rm, rd;
	if (!valid_gregorian_p(y, m, d,
			       &nth, &ry,
			       &rm, &rd))
	    rb_raise(eDateError, "invalid date");
	set_to_simple(self, dat, nth, 0, sg, ry, rm, rd, HAVE_CIVIL);
    }
    else {
	VALUE nth;
	int ry, rm, rd, rjd, ns;
	if (!valid_civil_p(y, m, d, sg,
			   &nth, &ry,
			   &rm, &rd, &rjd,
			   &ns))
	    rb_raise(eDateError, "invalid date");
	set_to_simple(self, dat, nth, rjd, sg, ry, rm, rd, HAVE_JD | HAVE_CIVIL);
    }
    ret = self;
    add_frac();
    return ret;
}
  Class Method Details
    ._httpdate(string, limit: 128)  ⇒ Hash   
Returns a hash of values parsed from string, which should be a valid HTTP date format:
d = Date.new(2001, 2, 3)
s = d.httpdate # => "Sat, 03 Feb 2001 00:00:00 GMT"
Date._httpdate(s)
# => {:wday=>6, :mday=>3, :mon=>2, :year=>2001, :hour=>0, :min=>0, :sec=>0, :zone=>"GMT", :offset=>0}Related: .httpdate (returns a Date object).
# File 'ext/date/date_core.c', line 4893
static VALUE
date_s__httpdate(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, opt;
    rb_scan_args(argc, argv, "1:", &str, &opt);
    check_limit(str, opt);
    return date__httpdate(str);
}
  
    ._iso8601(string, limit: 128)  ⇒ Hash   
Returns a hash of values parsed from string, which should contain an ISO 8601 formatted date:
d = Date.new(2001, 2, 3)
s = d.iso8601    # => "2001-02-03"
Date._iso8601(s) # => {:mday=>3, :year=>2001, :mon=>2}See argument limit.
Related: .iso8601 (returns a Date object).
# File 'ext/date/date_core.c', line 4617
static VALUE
date_s__iso8601(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, opt;
    rb_scan_args(argc, argv, "1:", &str, &opt);
    check_limit(str, opt);
    return date__iso8601(str);
}
  
    ._jisx0301(string, limit: 128)  ⇒ Hash   
Returns a hash of values parsed from string, which should be a valid JIS X 0301 date format:
d = Date.new(2001, 2, 3)
s = d.jisx0301    # => "H13.02.03"
Date._jisx0301(s) # => {:year=>2001, :mon=>2, :mday=>3}See argument limit.
Related: .jisx0301 (returns a Date object).
# File 'ext/date/date_core.c', line 4962
static VALUE
date_s__jisx0301(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, opt;
    rb_scan_args(argc, argv, "1:", &str, &opt);
    check_limit(str, opt);
    return date__jisx0301(str);
}
  ._load(s)
# File 'ext/date/date_core.c', line 7641
static VALUE
date_s__load(VALUE klass, VALUE s)
{
    VALUE a, obj;
    a = rb_marshal_load(s);
    obj = d_lite_s_alloc(klass);
    return d_lite_marshal_load(obj, a);
}
  
    ._parse(string, comp = true, limit: 128)  ⇒ Hash   
Note: This method recognizes many forms in string, but it is not a validator. For formats, see “Specialized Format Strings” in Formats for Dates and Times
If string does not specify a valid date, the result is unpredictable; consider using ._strptime instead.
Returns a hash of values parsed from string:
Date._parse('2001-02-03') # => {:year=>2001, :mon=>2, :mday=>3}If comp is true and the given year is in the range (0..99), the current century is supplied; otherwise, the year is taken as given:
Date._parse('01-02-03', true)  # => {:year=>2001, :mon=>2, :mday=>3}
Date._parse('01-02-03', false) # => {:year=>1, :mon=>2, :mday=>3}See argument limit.
Related: .parse(returns a Date object).
# File 'ext/date/date_core.c', line 4529
static VALUE
date_s__parse(int argc, VALUE *argv, VALUE klass)
{
    return date_s__parse_internal(argc, argv, klass);
}
  
    
      ._rfc822(string, limit: 128)  ⇒ Hash 
      ._rfc2822(string, limit: 128)  ⇒ Hash 
    
  
Hash 
      ._rfc2822(string, limit: 128)  ⇒ Hash 
    Alias for ._rfc822.
    ._rfc3339(string, limit: 128)  ⇒ Hash   
Returns a hash of values parsed from string, which should be a valid RFC 3339 format:
d = Date.new(2001, 2, 3)
s = d.rfc3339     # => "2001-02-03T00:00:00+00:00"
Date._rfc3339(s)
# => {:year=>2001, :mon=>2, :mday=>3, :hour=>0, :min=>0, :sec=>0, :zone=>"+00:00", :offset=>0}See argument limit.
Related: .rfc3339 (returns a Date object).
# File 'ext/date/date_core.c', line 4687
static VALUE
date_s__rfc3339(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, opt;
    rb_scan_args(argc, argv, "1:", &str, &opt);
    check_limit(str, opt);
    return date__rfc3339(str);
}
  
    ._rfc822(string, limit: 128)  ⇒ Hash     Also known as: ._rfc2822
  
Returns a hash of values parsed from string, which should be a valid RFC 2822 date format:
d = Date.new(2001, 2, 3)
s = d.rfc2822 # => "Sat, 3 Feb 2001 00:00:00 +0000"
Date._rfc2822(s)
# => {:wday=>6, :mday=>3, :mon=>2, :year=>2001, :hour=>0, :min=>0, :sec=>0, :zone=>"+0000", :offset=>0}See argument limit.
Related: .rfc2822 (returns a Date object).
# File 'ext/date/date_core.c', line 4825
static VALUE
date_s__rfc2822(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, opt;
    rb_scan_args(argc, argv, "1:", &str, &opt);
    check_limit(str, opt);
    return date__rfc2822(str);
}
  
    ._strptime(string, format = '%F')  ⇒ Hash   
Returns a hash of values parsed from string according to the given format:
Date._strptime('2001-02-03', '%Y-%m-%d') # => {:year=>2001, :mon=>2, :mday=>3}For other formats, see Formats for Dates and Times. (Unlike #strftime, does not support flags and width.)
See also strptime(3).
Related: .strptime (returns a Date object).
# File 'ext/date/date_core.c', line 4393
static VALUE
date_s__strptime(int argc, VALUE *argv, VALUE klass)
{
    return date_s__strptime_internal(argc, argv, klass, "%F");
}
  
    ._xmlschema(string, limit: 128)  ⇒ Hash   
Returns a hash of values parsed from string, which should be a valid XML date format:
d = Date.new(2001, 2, 3)
s = d.xmlschema    # => "2001-02-03"
Date._xmlschema(s) # => {:year=>2001, :mon=>2, :mday=>3}See argument limit.
Related: .xmlschema (returns a Date object).
# File 'ext/date/date_core.c', line 4756
static VALUE
date_s__xmlschema(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, opt;
    rb_scan_args(argc, argv, "1:", &str, &opt);
    check_limit(str, opt);
    return date__xmlschema(str);
}
  .civil(*args)
Same as .new.
# File 'ext/date/date_core.c', line 3470
static VALUE
date_s_civil(int argc, VALUE *argv, VALUE klass)
{
    return date_initialize(argc, argv, d_lite_s_alloc_simple(klass));
}
  
    .commercial(cwyear = -4712, cweek = 1, cwday = 1, start = Date::ITALY)  ⇒ Date   
Returns a new Date object constructed from the arguments.
Argument #cwyear gives the year, and should be an integer.
Argument #cweek gives the index of the week within the year, and should be in range (1..53) or (-53..-1); in some years, 53 or -53 will be out-of-range; if negative, counts backward from the end of the year:
Date.commercial(2022, 1, 1).to_s  # => "2022-01-03"
Date.commercial(2022, 52, 1).to_s # => "2022-12-26"Argument #cwday gives the indes of the weekday within the week, and should be in range (1..7) or (-7..-1); 1 or -7 is Monday; if negative, counts backward from the end of the week:
Date.commercial(2022, 1, 1).to_s  # => "2022-01-03"
Date.commercial(2022, 1, -7).to_s # => "2022-01-03"When #cweek is 1:
- 
If January 1 is a Friday, Saturday, or Sunday, the first week begins in the week after: Date::ABBR_DAYNAMES[Date.new(2023, 1, 1).wday] # => "Sun" Date.commercial(2023, 1, 1).to_s # => "2023-01-02" Date.commercial(2023, 1, 7).to_s # => "2023-01-08"
- 
Otherwise, the first week is the week of January 1, which may mean some of the days fall on the year before: Date::ABBR_DAYNAMES[Date.new(2020, 1, 1).wday] # => "Wed" Date.commercial(2020, 1, 1).to_s # => "2019-12-30" Date.commercial(2020, 1, 7).to_s # => "2020-01-05"
See argument start.
# File 'ext/date/date_core.c', line 3605
static VALUE
date_s_commercial(int argc, VALUE *argv, VALUE klass)
{
    VALUE vy, vw, vd, vsg, y, fr, fr2, ret;
    int w, d;
    double sg;
    rb_scan_args(argc, argv, "04", &vy, &vw, &vd, &vsg);
    y = INT2FIX(-4712);
    w = 1;
    d = 1;
    fr2 = INT2FIX(0);
    sg = DEFAULT_SG;
    switch (argc) {
      case 4:
	val2sg(vsg, sg);
      case 3:
        check_numeric(vd, "cwday");
	num2int_with_frac(d, positive_inf);
      case 2:
        check_numeric(vw, "cweek");
	w = NUM2INT(vw);
      case 1:
        check_numeric(vy, "year");
	y = vy;
    }
    {
	VALUE nth;
	int ry, rw, rd, rjd, ns;
	if (!valid_commercial_p(y, w, d, sg,
				&nth, &ry,
				&rw, &rd, &rjd,
				&ns))
	    rb_raise(eDateError, "invalid date");
	ret = d_simple_new_internal(klass,
				    nth, rjd,
				    sg,
				    0, 0, 0,
				    HAVE_JD);
    }
    add_frac();
    return ret;
}
  
    
      .leap?(year)  ⇒ Boolean 
      .gregorian_leap?(year)  ⇒ Boolean 
    
  
Boolean 
      .gregorian_leap?(year)  ⇒ Boolean 
    Alias for .leap?.
    .httpdate(string = 'Mon, 01 Jan -4712 00:00:00 GMT', start = Date::ITALY, limit: 128)  ⇒ Date   
Returns a new Date object with values parsed from string, which should be a valid HTTP date format:
d = Date.new(2001, 2, 3)
  s = d.httpdate   # => "Sat, 03 Feb 2001 00:00:00 GMT"
  Date.httpdate(s) # => #<Date: 2001-02-03>See:
Related: ._httpdate (returns a hash).
# File 'ext/date/date_core.c', line 4923
static VALUE
date_s_httpdate(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, sg, opt;
    argc = rb_scan_args(argc, argv, "02:", &str, &sg, &opt);
    switch (argc) {
      case 0:
	str = rb_str_new2(JULIAN_EPOCH_DATETIME_HTTPDATE);
      case 1:
	sg = INT2FIX(DEFAULT_SG);
    }
    {
        int argc2 = 1;
        VALUE argv2[2], hash;
        argv2[0] = str;
        if (!NIL_P(opt)) argv2[argc2++] = opt;
	hash = date_s__httpdate(argc2, argv2, klass);
	return d_new_by_frags(klass, hash, sg);
    }
}
  
    .iso8601(string = '-4712-01-01', start = Date::ITALY, limit: 128)  ⇒ Date   
Returns a new Date object with values parsed from string, which should contain an ISO 8601 formatted date:
d = Date.new(2001, 2, 3)
s = d.iso8601   # => "2001-02-03"
Date.iso8601(s) # => #<Date: 2001-02-03>See:
Related: ._iso8601 (returns a hash).
# File 'ext/date/date_core.c', line 4647
static VALUE
date_s_iso8601(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, sg, opt;
    argc = rb_scan_args(argc, argv, "02:", &str, &sg, &opt);
    switch (argc) {
      case 0:
	str = rb_str_new2(JULIAN_EPOCH_DATE);
      case 1:
	sg = INT2FIX(DEFAULT_SG);
    }
    {
        int argc2 = 1;
        VALUE argv2[2], hash;
        argv2[0] = str;
        if (!NIL_P(opt)) argv2[argc2++] = opt;
	hash = date_s__iso8601(argc2, argv2, klass);
	return d_new_by_frags(klass, hash, sg);
    }
}
  
    .jd(jd = 0, start = Date::ITALY)  ⇒ Date   
Returns a new Date object formed from the arguments:
Date.jd(2451944).to_s # => "2001-02-03"
Date.jd(2451945).to_s # => "2001-02-04"
Date.jd(0).to_s       # => "-4712-01-01"The returned date is:
- 
Gregorian, if the argument is greater than or equal to #start: Date::ITALY # => 2299161 Date.jd(Date::ITALY).gregorian? # => true Date.jd(Date::ITALY + 1).gregorian? # => true
- 
Julian, otherwise Date.jd(Date::ITALY - 1).julian? # => true
See argument start.
Related: .new.
# File 'ext/date/date_core.c', line 3357
static VALUE
date_s_jd(int argc, VALUE *argv, VALUE klass)
{
    VALUE vjd, vsg, jd, fr, fr2, ret;
    double sg;
    rb_scan_args(argc, argv, "02", &vjd, &vsg);
    jd = INT2FIX(0);
    fr2 = INT2FIX(0);
    sg = DEFAULT_SG;
    switch (argc) {
      case 2:
	val2sg(vsg, sg);
      case 1:
        check_numeric(vjd, "jd");
	num2num_with_frac(jd, positive_inf);
    }
    {
	VALUE nth;
	int rjd;
	decode_jd(jd, &nth, &rjd);
	ret = d_simple_new_internal(klass,
				    nth, rjd,
				    sg,
				    0, 0, 0,
				    HAVE_JD);
    }
    add_frac();
    return ret;
}
  
    .jisx0301(string = '-4712-01-01', start = Date::ITALY, limit: 128)  ⇒ Date   
Returns a new Date object with values parsed from string, which should be a valid JIS X 0301 format:
d = Date.new(2001, 2, 3)
s = d.jisx0301   # => "H13.02.03"
Date.jisx0301(s) # => #<Date: 2001-02-03>For no-era year, legacy format, Heisei is assumed.
Date.jisx0301('13.02.03') # => #<Date: 2001-02-03>See:
Related: ._jisx0301 (returns a hash).
# File 'ext/date/date_core.c', line 4995
static VALUE
date_s_jisx0301(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, sg, opt;
    argc = rb_scan_args(argc, argv, "02:", &str, &sg, &opt);
    switch (argc) {
      case 0:
	str = rb_str_new2(JULIAN_EPOCH_DATE);
      case 1:
	sg = INT2FIX(DEFAULT_SG);
    }
    {
        int argc2 = 1;
        VALUE argv2[2], hash;
        argv2[0] = str;
        if (!NIL_P(opt)) argv2[argc2++] = opt;
	hash = date_s__jisx0301(argc2, argv2, klass);
	return d_new_by_frags(klass, hash, sg);
    }
}
  
    .julian_leap?(year)  ⇒ Boolean   
Returns true if the given year is a leap year in the proleptic Julian calendar, false otherwise:
Date.julian_leap?(1900) # => true
Date.julian_leap?(1901) # => falseRelated: .gregorian_leap?.
# File 'ext/date/date_core.c', line 2971
static VALUE
date_s_julian_leap_p(VALUE klass, VALUE y)
{
    VALUE nth;
    int ry;
    check_numeric(y, "year");
    decode_year(y, +1, &nth, &ry);
    return f_boolcast(c_julian_leap_p(ry));
}
  
    .leap?(year)  ⇒ Boolean     Also known as: .gregorian_leap?
  
Returns true if the given year is a leap year in the proleptic Gregorian calendar, false otherwise:
Date.gregorian_leap?(2000) # => true
Date.gregorian_leap?(2001) # => falseRelated: .julian_leap?.
# File 'ext/date/date_core.c', line 2994
static VALUE
date_s_gregorian_leap_p(VALUE klass, VALUE y)
{
    VALUE nth;
    int ry;
    check_numeric(y, "year");
    decode_year(y, -1, &nth, &ry);
    return f_boolcast(c_gregorian_leap_p(ry));
}
  .new!(*args)
# File 'ext/date/date_core.c', line 3146
static VALUE
date_s_new_bang(int argc, VALUE *argv, VALUE klass)
{
    VALUE ajd, of, sg, nth, sf;
    int jd, df, rof;
    double rsg;
    rb_scan_args(argc, argv, "03", &ajd, &of, &sg);
    switch (argc) {
      case 0:
	ajd = INT2FIX(0);
      case 1:
	of = INT2FIX(0);
      case 2:
	sg = INT2FIX(DEFAULT_SG);
    }
    old_to_new(ajd, of, sg,
	       &nth, &jd, &df, &sf, &rof, &rsg);
    if (!df && f_zero_p(sf) && !rof)
	return d_simple_new_internal(klass,
				     nth, jd,
				     rsg,
				     0, 0, 0,
				     HAVE_JD);
    else
	return d_complex_new_internal(klass,
				      nth, jd,
				      df, sf,
				      rof, rsg,
				      0, 0, 0,
				      0, 0, 0,
				      HAVE_JD | HAVE_DF);
}
  .nth_kday(*args)
# File 'ext/date/date_core.c', line 3706
static VALUE
date_s_nth_kday(int argc, VALUE *argv, VALUE klass)
{
    VALUE vy, vm, vn, vk, vsg, y, fr, fr2, ret;
    int m, n, k;
    double sg;
    rb_scan_args(argc, argv, "05", &vy, &vm, &vn, &vk, &vsg);
    y = INT2FIX(-4712);
    m = 1;
    n = 1;
    k = 1;
    fr2 = INT2FIX(0);
    sg = DEFAULT_SG;
    switch (argc) {
      case 5:
	val2sg(vsg, sg);
      case 4:
	num2int_with_frac(k, positive_inf);
      case 3:
	n = NUM2INT(vn);
      case 2:
	m = NUM2INT(vm);
      case 1:
	y = vy;
    }
    {
	VALUE nth;
	int ry, rm, rn, rk, rjd, ns;
	if (!valid_nth_kday_p(y, m, n, k, sg,
			      &nth, &ry,
			      &rm, &rn, &rk, &rjd,
			      &ns))
	    rb_raise(eDateError, "invalid date");
	ret = d_simple_new_internal(klass,
				    nth, rjd,
				    sg,
				    0, 0, 0,
				    HAVE_JD);
    }
    add_frac();
    return ret;
}
  
    .ordinal(year = -4712, yday = 1, start = Date::ITALY)  ⇒ Date   
Returns a new Date object formed fom the arguments.
With no arguments, returns the date for January 1, -4712:
Date.ordinal.to_s # => "-4712-01-01"With argument #year, returns the date for January 1 of that year:
Date.ordinal(2001).to_s  # => "2001-01-01"
Date.ordinal(-2001).to_s # => "-2001-01-01"With positive argument #yday == n, returns the date for the nth day of the given year:
Date.ordinal(2001, 14).to_s # => "2001-01-14"With negative argument #yday, counts backward from the end of the year:
Date.ordinal(2001, -14).to_s # => "2001-12-18"Raises an exception if #yday is zero or out of range.
See argument start.
# File 'ext/date/date_core.c', line 3422
static VALUE
date_s_ordinal(int argc, VALUE *argv, VALUE klass)
{
    VALUE vy, vd, vsg, y, fr, fr2, ret;
    int d;
    double sg;
    rb_scan_args(argc, argv, "03", &vy, &vd, &vsg);
    y = INT2FIX(-4712);
    d = 1;
    fr2 = INT2FIX(0);
    sg = DEFAULT_SG;
    switch (argc) {
      case 3:
	val2sg(vsg, sg);
      case 2:
        check_numeric(vd, "yday");
	num2int_with_frac(d, positive_inf);
      case 1:
        check_numeric(vy, "year");
	y = vy;
    }
    {
	VALUE nth;
	int ry, rd, rjd, ns;
	if (!valid_ordinal_p(y, d, sg,
			     &nth, &ry,
			     &rd, &rjd,
			     &ns))
	    rb_raise(eDateError, "invalid date");
	ret = d_simple_new_internal(klass,
				     nth, rjd,
				     sg,
				     0, 0, 0,
				     HAVE_JD);
    }
    add_frac();
    return ret;
}
  
    .parse(string = '-4712-01-01', comp = true, start = Date::ITALY, limit: 128)  ⇒ Date   
Note: This method recognizes many forms in string, but it is not a validator. For formats, see “Specialized Format Strings” in Formats for Dates and Times If string does not specify a valid date, the result is unpredictable; consider using ._strptime instead.
Returns a new Date object with values parsed from string:
Date.parse('2001-02-03')   # => #<Date: 2001-02-03>
Date.parse('20010203')     # => #<Date: 2001-02-03>
Date.parse('3rd Feb 2001') # => #<Date: 2001-02-03>If comp is true and the given year is in the range (0..99), the current century is supplied; otherwise, the year is taken as given:
Date.parse('01-02-03', true)  # => #<Date: 2001-02-03>
Date.parse('01-02-03', false) # => #<Date: 0001-02-03>See:
Related: ._parse (returns a hash).
# File 'ext/date/date_core.c', line 4568
static VALUE
date_s_parse(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, comp, sg, opt;
    argc = rb_scan_args(argc, argv, "03:", &str, &comp, &sg, &opt);
    switch (argc) {
      case 0:
	str = rb_str_new2(JULIAN_EPOCH_DATE);
      case 1:
	comp = Qtrue;
      case 2:
	sg = INT2FIX(DEFAULT_SG);
    }
    {
        int argc2 = 2;
	VALUE argv2[3], hash;
        argv2[0] = str;
        argv2[1] = comp;
        if (!NIL_P(opt)) argv2[argc2++] = opt;
	hash = date_s__parse(argc2, argv2, klass);
	return d_new_by_frags(klass, hash, sg);
    }
}
  
    
      .rfc822(string = 'Mon, 1 Jan -4712 00:00:00 +0000', start = Date::ITALY, limit: 128)  ⇒ Date 
      .rfc2822(string = 'Mon, 1 Jan -4712 00:00:00 +0000', start = Date::ITALY, limit: 128)  ⇒ Date 
    
  
Date 
      .rfc2822(string = 'Mon, 1 Jan -4712 00:00:00 +0000', start = Date::ITALY, limit: 128)  ⇒ Date 
    Alias for .rfc822.
    .rfc3339(string = '-4712-01-01T00:00:00+00:00', start = Date::ITALY, limit: 128)  ⇒ Date   
Returns a new Date object with values parsed from string, which should be a valid RFC 3339 format:
d = Date.new(2001, 2, 3)
s = d.rfc3339   # => "2001-02-03T00:00:00+00:00"
Date.rfc3339(s) # => #<Date: 2001-02-03>See:
Related: ._rfc3339 (returns a hash).
# File 'ext/date/date_core.c', line 4717
static VALUE
date_s_rfc3339(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, sg, opt;
    argc = rb_scan_args(argc, argv, "02:", &str, &sg, &opt);
    switch (argc) {
      case 0:
	str = rb_str_new2(JULIAN_EPOCH_DATETIME);
      case 1:
	sg = INT2FIX(DEFAULT_SG);
    }
    {
        int argc2 = 1;
        VALUE argv2[2], hash;
        argv2[0] = str;
        if (!NIL_P(opt)) argv2[argc2++] = opt;
	hash = date_s__rfc3339(argc2, argv2, klass);
	return d_new_by_frags(klass, hash, sg);
    }
}
  
    .rfc822(string = 'Mon, 1 Jan -4712 00:00:00 +0000', start = Date::ITALY, limit: 128)  ⇒ Date     Also known as: .rfc2822
  
# File 'ext/date/date_core.c', line 4855
static VALUE
date_s_rfc2822(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, sg, opt;
    argc = rb_scan_args(argc, argv, "02:", &str, &sg, &opt);
    switch (argc) {
      case 0:
	str = rb_str_new2(JULIAN_EPOCH_DATETIME_RFC3339);
      case 1:
	sg = INT2FIX(DEFAULT_SG);
    }
    {
        int argc2 = 1;
        VALUE argv2[2], hash;
        argv2[0] = str;
        if (!NIL_P(opt)) argv2[argc2++] = opt;
	hash = date_s__rfc2822(argc2, argv2, klass);
	return d_new_by_frags(klass, hash, sg);
    }
}
  
    .strptime(string = '-4712-01-01', format = '%F', start = Date::ITALY)  ⇒ Date   
Returns a new Date object with values parsed from string, according to the given format:
Date.strptime('2001-02-03', '%Y-%m-%d')  # => #<Date: 2001-02-03>
Date.strptime('03-02-2001', '%d-%m-%Y')  # => #<Date: 2001-02-03>
Date.strptime('2001-034', '%Y-%j')       # => #<Date: 2001-02-03>
Date.strptime('2001-W05-6', '%G-W%V-%u') # => #<Date: 2001-02-03>
Date.strptime('2001 04 6', '%Y %U %w')   # => #<Date: 2001-02-03>
Date.strptime('2001 05 6', '%Y %W %u')   # => #<Date: 2001-02-03>
Date.strptime('sat3feb01', '%a%d%b%y')   # => #<Date: 2001-02-03>For other formats, see Formats for Dates and Times. (Unlike #strftime, does not support flags and width.)
See argument start.
See also strptime(3).
Related: ._strptime (returns a hash).
# File 'ext/date/date_core.c', line 4424
static VALUE
date_s_strptime(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, fmt, sg;
    rb_scan_args(argc, argv, "03", &str, &fmt, &sg);
    switch (argc) {
      case 0:
	str = rb_str_new2(JULIAN_EPOCH_DATE);
      case 1:
	fmt = rb_str_new2("%F");
      case 2:
	sg = INT2FIX(DEFAULT_SG);
    }
    {
	VALUE argv2[2], hash;
	argv2[0] = str;
	argv2[1] = fmt;
	hash = date_s__strptime(2, argv2, klass);
	return d_new_by_frags(klass, hash, sg);
    }
}
  .test_all
# File 'ext/date/date_core.c', line 9412
static VALUE
date_s_test_all(VALUE klass)
{
    if (date_s_test_civil(klass) == Qfalse)
	return Qfalse;
    if (date_s_test_ordinal(klass) == Qfalse)
	return Qfalse;
    if (date_s_test_commercial(klass) == Qfalse)
	return Qfalse;
    if (date_s_test_weeknum(klass) == Qfalse)
	return Qfalse;
    if (date_s_test_nth_kday(klass) == Qfalse)
	return Qfalse;
    if (date_s_test_unit_conv(klass) == Qfalse)
	return Qfalse;
    return Qtrue;
}
  .test_civil
# File 'ext/date/date_core.c', line 9148
static VALUE
date_s_test_civil(VALUE klass)
{
    if (!test_civil(MIN_JD, MIN_JD + 366, GREGORIAN))
	return Qfalse;
    if (!test_civil(2305814, 2598007, GREGORIAN))
	return Qfalse;
    if (!test_civil(MAX_JD - 366, MAX_JD, GREGORIAN))
	return Qfalse;
    if (!test_civil(MIN_JD, MIN_JD + 366, ITALY))
	return Qfalse;
    if (!test_civil(2305814, 2598007, ITALY))
	return Qfalse;
    if (!test_civil(MAX_JD - 366, MAX_JD, ITALY))
	return Qfalse;
    return Qtrue;
}
  .test_commercial
# File 'ext/date/date_core.c', line 9232
static VALUE
date_s_test_commercial(VALUE klass)
{
    if (!test_commercial(MIN_JD, MIN_JD + 366, GREGORIAN))
	return Qfalse;
    if (!test_commercial(2305814, 2598007, GREGORIAN))
	return Qfalse;
    if (!test_commercial(MAX_JD - 366, MAX_JD, GREGORIAN))
	return Qfalse;
    if (!test_commercial(MIN_JD, MIN_JD + 366, ITALY))
	return Qfalse;
    if (!test_commercial(2305814, 2598007, ITALY))
	return Qfalse;
    if (!test_commercial(MAX_JD - 366, MAX_JD, ITALY))
	return Qfalse;
    return Qtrue;
}
  .test_nth_kday
# File 'ext/date/date_core.c', line 9320
static VALUE
date_s_test_nth_kday(VALUE klass)
{
    if (!test_nth_kday(MIN_JD, MIN_JD + 366, GREGORIAN))
	return Qfalse;
    if (!test_nth_kday(2305814, 2598007, GREGORIAN))
	return Qfalse;
    if (!test_nth_kday(MAX_JD - 366, MAX_JD, GREGORIAN))
	return Qfalse;
    if (!test_nth_kday(MIN_JD, MIN_JD + 366, ITALY))
	return Qfalse;
    if (!test_nth_kday(2305814, 2598007, ITALY))
	return Qfalse;
    if (!test_nth_kday(MAX_JD - 366, MAX_JD, ITALY))
	return Qfalse;
    return Qtrue;
}
  .test_ordinal
# File 'ext/date/date_core.c', line 9190
static VALUE
date_s_test_ordinal(VALUE klass)
{
    if (!test_ordinal(MIN_JD, MIN_JD + 366, GREGORIAN))
	return Qfalse;
    if (!test_ordinal(2305814, 2598007, GREGORIAN))
	return Qfalse;
    if (!test_ordinal(MAX_JD - 366, MAX_JD, GREGORIAN))
	return Qfalse;
    if (!test_ordinal(MIN_JD, MIN_JD + 366, ITALY))
	return Qfalse;
    if (!test_ordinal(2305814, 2598007, ITALY))
	return Qfalse;
    if (!test_ordinal(MAX_JD - 366, MAX_JD, ITALY))
	return Qfalse;
    return Qtrue;
}
  .test_unit_conv
# File 'ext/date/date_core.c', line 9397
static VALUE
date_s_test_unit_conv(VALUE klass)
{
    if (!test_unit_v2v_iter(sec_to_day, day_to_sec))
	return Qfalse;
    if (!test_unit_v2v_iter(ms_to_sec, sec_to_ms))
	return Qfalse;
    if (!test_unit_v2v_iter(ns_to_day, day_to_ns))
	return Qfalse;
    if (!test_unit_v2v_iter(ns_to_sec, sec_to_ns))
	return Qfalse;
    return Qtrue;
}
  .test_weeknum
# File 'ext/date/date_core.c', line 9274
static VALUE
date_s_test_weeknum(VALUE klass)
{
    int f;
    for (f = 0; f <= 1; f++) {
	if (!test_weeknum(MIN_JD, MIN_JD + 366, f, GREGORIAN))
	    return Qfalse;
	if (!test_weeknum(2305814, 2598007, f, GREGORIAN))
	    return Qfalse;
	if (!test_weeknum(MAX_JD - 366, MAX_JD, f, GREGORIAN))
	    return Qfalse;
	if (!test_weeknum(MIN_JD, MIN_JD + 366, f, ITALY))
	    return Qfalse;
	if (!test_weeknum(2305814, 2598007, f, ITALY))
	    return Qfalse;
	if (!test_weeknum(MAX_JD - 366, MAX_JD, f, ITALY))
	    return Qfalse;
    }
    return Qtrue;
}
  
    .today(start = Date::ITALY)  ⇒ Date   
# File 'ext/date/date_core.c', line 3789
static VALUE
date_s_today(int argc, VALUE *argv, VALUE klass)
{
    VALUE vsg, nth, ret;
    double sg;
    time_t t;
    struct tm tm;
    int y, ry, m, d;
    rb_scan_args(argc, argv, "01", &vsg);
    if (argc < 1)
	sg = DEFAULT_SG;
    else
	val2sg(vsg, sg);
    if (time(&t) == -1)
	rb_sys_fail("time");
    tzset();
    if (!localtime_r(&t, &tm))
	rb_sys_fail("localtime");
    y = tm.tm_year + 1900;
    m = tm.tm_mon + 1;
    d = tm.tm_mday;
    decode_year(INT2FIX(y), -1, &nth, &ry);
    ret = d_simple_new_internal(klass,
				nth, 0,
				GREGORIAN,
				ry, m, d,
				HAVE_CIVIL);
    {
	get_d1(ret);
	set_sg(dat, sg);
    }
    return ret;
}
  
    
      .valid_date?(year, month, mday, start = Date::ITALY)  ⇒ Boolean 
      .valid_civil?(year, month, mday, start = Date::ITALY)  ⇒ Boolean 
    
  
Boolean 
      .valid_civil?(year, month, mday, start = Date::ITALY)  ⇒ Boolean 
    Alias for .valid_date?.
    .valid_commercial?(cwyear, cweek, cwday, start = Date::ITALY)  ⇒ Boolean   
Returns true if the arguments define a valid commercial date, false otherwise:
Date.valid_commercial?(2001, 5, 6) # => true
Date.valid_commercial?(2001, 5, 8) # => falseSee .commercial.
See argument start.
Related: .jd, .commercial.
# File 'ext/date/date_core.c', line 2777
static VALUE
date_s_valid_commercial_p(int argc, VALUE *argv, VALUE klass)
{
    VALUE vy, vw, vd, vsg;
    VALUE argv2[4];
    rb_scan_args(argc, argv, "31", &vy, &vw, &vd, &vsg);
    RETURN_FALSE_UNLESS_NUMERIC(vy);
    RETURN_FALSE_UNLESS_NUMERIC(vw);
    RETURN_FALSE_UNLESS_NUMERIC(vd);
    argv2[0] = vy;
    argv2[1] = vw;
    argv2[2] = vd;
    if (argc < 4)
	argv2[3] = INT2FIX(DEFAULT_SG);
    else
	argv2[3] = vsg;
    if (NIL_P(valid_commercial_sub(4, argv2, klass, 0)))
	return Qfalse;
    return Qtrue;
}
  
    .valid_date?(year, month, mday, start = Date::ITALY)  ⇒ Boolean     Also known as: .valid_civil?
  
# File 'ext/date/date_core.c', line 2599
static VALUE
date_s_valid_civil_p(int argc, VALUE *argv, VALUE klass)
{
    VALUE vy, vm, vd, vsg;
    VALUE argv2[4];
    rb_scan_args(argc, argv, "31", &vy, &vm, &vd, &vsg);
    RETURN_FALSE_UNLESS_NUMERIC(vy);
    RETURN_FALSE_UNLESS_NUMERIC(vm);
    RETURN_FALSE_UNLESS_NUMERIC(vd);
    argv2[0] = vy;
    argv2[1] = vm;
    argv2[2] = vd;
    if (argc < 4)
	argv2[3] = INT2FIX(DEFAULT_SG);
    else
	argv2[3] = vsg;
    if (NIL_P(valid_civil_sub(4, argv2, klass, 0)))
	return Qfalse;
    return Qtrue;
}
  
    .valid_jd?(jd, start = Date::ITALY)  ⇒ true   
# File 'ext/date/date_core.c', line 2505
static VALUE
date_s_valid_jd_p(int argc, VALUE *argv, VALUE klass)
{
    VALUE vjd, vsg;
    VALUE argv2[2];
    rb_scan_args(argc, argv, "11", &vjd, &vsg);
    RETURN_FALSE_UNLESS_NUMERIC(vjd);
    argv2[0] = vjd;
    if (argc < 2)
	argv2[1] = INT2FIX(DEFAULT_SG);
    else
	argv2[1] = vsg;
    if (NIL_P(valid_jd_sub(2, argv2, klass, 0)))
	return Qfalse;
    return Qtrue;
}
  
    .valid_ordinal?(year, yday, start = Date::ITALY)  ⇒ Boolean   
# File 'ext/date/date_core.c', line 2687
static VALUE
date_s_valid_ordinal_p(int argc, VALUE *argv, VALUE klass)
{
    VALUE vy, vd, vsg;
    VALUE argv2[3];
    rb_scan_args(argc, argv, "21", &vy, &vd, &vsg);
    RETURN_FALSE_UNLESS_NUMERIC(vy);
    RETURN_FALSE_UNLESS_NUMERIC(vd);
    argv2[0] = vy;
    argv2[1] = vd;
    if (argc < 3)
	argv2[2] = INT2FIX(DEFAULT_SG);
    else
	argv2[2] = vsg;
    if (NIL_P(valid_ordinal_sub(3, argv2, klass, 0)))
	return Qfalse;
    return Qtrue;
}
  .weeknum(*args)
# File 'ext/date/date_core.c', line 3656
static VALUE
date_s_weeknum(int argc, VALUE *argv, VALUE klass)
{
    VALUE vy, vw, vd, vf, vsg, y, fr, fr2, ret;
    int w, d, f;
    double sg;
    rb_scan_args(argc, argv, "05", &vy, &vw, &vd, &vf, &vsg);
    y = INT2FIX(-4712);
    w = 0;
    d = 1;
    f = 0;
    fr2 = INT2FIX(0);
    sg = DEFAULT_SG;
    switch (argc) {
      case 5:
	val2sg(vsg, sg);
      case 4:
	f = NUM2INT(vf);
      case 3:
	num2int_with_frac(d, positive_inf);
      case 2:
	w = NUM2INT(vw);
      case 1:
	y = vy;
    }
    {
	VALUE nth;
	int ry, rw, rd, rjd, ns;
	if (!valid_weeknum_p(y, w, d, f, sg,
			     &nth, &ry,
			     &rw, &rd, &rjd,
			     &ns))
	    rb_raise(eDateError, "invalid date");
	ret = d_simple_new_internal(klass,
				    nth, rjd,
				    sg,
				    0, 0, 0,
				    HAVE_JD);
    }
    add_frac();
    return ret;
}
  
    .xmlschema(string = '-4712-01-01', start = Date::ITALY, limit: 128)  ⇒ Date   
Returns a new Date object with values parsed from string, which should be a valid XML date format:
d = Date.new(2001, 2, 3)
s = d.xmlschema   # => "2001-02-03"
Date.xmlschema(s) # => #<Date: 2001-02-03>See:
Related: ._xmlschema (returns a hash).
# File 'ext/date/date_core.c', line 4785
static VALUE
date_s_xmlschema(int argc, VALUE *argv, VALUE klass)
{
    VALUE str, sg, opt;
    argc = rb_scan_args(argc, argv, "02:", &str, &sg, &opt);
    switch (argc) {
      case 0:
	str = rb_str_new2(JULIAN_EPOCH_DATE);
      case 1:
	sg = INT2FIX(DEFAULT_SG);
    }
    {
        int argc2 = 1;
        VALUE argv2[2], hash;
        argv2[0] = str;
        if (!NIL_P(opt)) argv2[argc2++] = opt;
	hash = date_s__xmlschema(argc2, argv2, klass);
	return d_new_by_frags(klass, hash, sg);
    }
}
  Instance Attribute Details
    #friday?  ⇒ Boolean  (readonly)  
Returns true if self is a Friday, false otherwise.
# File 'ext/date/date_core.c', line 5532
static VALUE
d_lite_friday_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_wday(dat) == 5);
}
  
    #gregorian  ⇒ Date  (readonly)  
Equivalent to #new_start with argument GREGORIAN.
# File 'ext/date/date_core.c', line 5884
static VALUE
d_lite_gregorian(VALUE self)
{
    return dup_obj_with_new_start(self, GREGORIAN);
}
  
    #gregorian?  ⇒ Boolean  (readonly)  
# File 'ext/date/date_core.c', line 5697
static VALUE
d_lite_gregorian_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_gregorian_p(dat));
}
  
    #infinite?  ⇒ Boolean  (readonly)  
Returns false
# File 'ext/date/lib/date.rb', line 13
def infinite? false end
    #julian  ⇒ Date  (readonly)  
Equivalent to #new_start with argument JULIAN.
# File 'ext/date/date_core.c', line 5872
static VALUE
d_lite_julian(VALUE self)
{
    return dup_obj_with_new_start(self, JULIAN);
}
  
    #julian?  ⇒ Boolean  (readonly)  
# File 'ext/date/date_core.c', line 5679
static VALUE
d_lite_julian_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_julian_p(dat));
}
  
    #leap?  ⇒ Boolean  (readonly)  
# File 'ext/date/date_core.c', line 5714
static VALUE
d_lite_leap_p(VALUE self)
{
    int rjd, ns, ry, rm, rd;
    get_d1(self);
    if (m_gregorian_p(dat))
	return f_boolcast(c_gregorian_leap_p(m_year(dat)));
    c_civil_to_jd(m_year(dat), 3, 1, m_virtual_sg(dat),
		  &rjd, &ns);
    c_jd_to_civil(rjd - 1, m_virtual_sg(dat), &ry, &rm, &rd);
    return f_boolcast(rd == 29);
}
  
    #monday?  ⇒ Boolean  (readonly)  
Returns true if self is a Monday, false otherwise.
# File 'ext/date/date_core.c', line 5480
static VALUE
d_lite_monday_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_wday(dat) == 1);
}
  
    #saturday?  ⇒ Boolean  (readonly)  
Returns true if self is a Saturday, false otherwise.
# File 'ext/date/date_core.c', line 5545
static VALUE
d_lite_saturday_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_wday(dat) == 6);
}
  
    #sunday?  ⇒ Boolean  (readonly)  
Returns true if self is a Sunday, false otherwise.
# File 'ext/date/date_core.c', line 5467
static VALUE
d_lite_sunday_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_wday(dat) == 0);
}
  
    #thursday?  ⇒ Boolean  (readonly)  
Returns true if self is a Thursday, false otherwise.
# File 'ext/date/date_core.c', line 5519
static VALUE
d_lite_thursday_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_wday(dat) == 4);
}
  
    #tuesday?  ⇒ Boolean  (readonly)  
Returns true if self is a Tuesday, false otherwise.
# File 'ext/date/date_core.c', line 5493
static VALUE
d_lite_tuesday_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_wday(dat) == 2);
}
  
    #wednesday?  ⇒ Boolean  (readonly)  
Returns true if self is a Wednesday, false otherwise.
# File 'ext/date/date_core.c', line 5506
static VALUE
d_lite_wednesday_p(VALUE self)
{
    get_d1(self);
    return f_boolcast(m_wday(dat) == 3);
}
  Instance Method Details
    #+(other)  ⇒ Date   
Returns a date object pointing other days after self.  The other should be a numeric value.  If the other is a fractional number, assumes its precision is at most nanosecond.
Date.new(2001,2,3) + 1    #=> #<Date: 2001-02-04 ...>
DateTime.new(2001,2,3) + Rational(1,2)
                          #=> #<DateTime: 2001-02-03T12:00:00+00:00 ...>
DateTime.new(2001,2,3) + Rational(-1,2)
                          #=> #<DateTime: 2001-02-02T12:00:00+00:00 ...>
DateTime.jd(0,12) + DateTime.new(2001,2,3).ajd
                          #=> #<DateTime: 2001-02-03T00:00:00+00:00 ...># File 'ext/date/date_core.c', line 5952
static VALUE
d_lite_plus(VALUE self, VALUE other)
{
    int try_rational = 1;
    get_d1(self);
  again:
    switch (TYPE(other)) {
      case T_FIXNUM:
	{
	    VALUE nth;
	    long t;
	    int jd;
	    nth = m_nth(dat);
	    t = FIX2LONG(other);
	    if (DIV(t, CM_PERIOD)) {
		nth = f_add(nth, INT2FIX(DIV(t, CM_PERIOD)));
		t = MOD(t, CM_PERIOD);
	    }
	    if (!t)
		jd = m_jd(dat);
	    else {
		jd = m_jd(dat) + (int)t;
		canonicalize_jd(nth, jd);
	    }
	    if (simple_dat_p(dat))
		return d_simple_new_internal(rb_obj_class(self),
					     nth, jd,
					     dat->s.sg,
					     0, 0, 0,
					     (dat->s.flags | HAVE_JD) &
					     ~HAVE_CIVIL);
	    else
		return d_complex_new_internal(rb_obj_class(self),
					      nth, jd,
					      dat->c.df, dat->c.sf,
					      dat->c.of, dat->c.sg,
					      0, 0, 0,
#ifndef USE_PACK
					      dat->c.hour,
					      dat->c.min,
					      dat->c.sec,
#else
					      EX_HOUR(dat->c.pc),
					      EX_MIN(dat->c.pc),
					      EX_SEC(dat->c.pc),
#endif
					      (dat->c.flags | HAVE_JD) &
					      ~HAVE_CIVIL);
	}
	break;
      case T_BIGNUM:
	{
	    VALUE nth;
	    int jd, s;
	    if (f_positive_p(other))
		s = +1;
	    else {
		s = -1;
		other = f_negate(other);
	    }
	    nth = f_idiv(other, INT2FIX(CM_PERIOD));
	    jd = FIX2INT(f_mod(other, INT2FIX(CM_PERIOD)));
	    if (s < 0) {
		nth = f_negate(nth);
		jd = -jd;
	    }
	    if (!jd)
		jd = m_jd(dat);
	    else {
		jd = m_jd(dat) + jd;
		canonicalize_jd(nth, jd);
	    }
	    if (f_zero_p(nth))
		nth = m_nth(dat);
	    else
		nth = f_add(m_nth(dat), nth);
	    if (simple_dat_p(dat))
		return d_simple_new_internal(rb_obj_class(self),
					     nth, jd,
					     dat->s.sg,
					     0, 0, 0,
					     (dat->s.flags | HAVE_JD) &
					     ~HAVE_CIVIL);
	    else
		return d_complex_new_internal(rb_obj_class(self),
					      nth, jd,
					      dat->c.df, dat->c.sf,
					      dat->c.of, dat->c.sg,
					      0, 0, 0,
#ifndef USE_PACK
					      dat->c.hour,
					      dat->c.min,
					      dat->c.sec,
#else
					      EX_HOUR(dat->c.pc),
					      EX_MIN(dat->c.pc),
					      EX_SEC(dat->c.pc),
#endif
					      (dat->c.flags | HAVE_JD) &
					      ~HAVE_CIVIL);
	}
	break;
      case T_FLOAT:
	{
	    double jd, o, tmp;
	    int s, df;
	    VALUE nth, sf;
	    o = RFLOAT_VALUE(other);
	    if (o > 0)
		s = +1;
	    else {
		s = -1;
		o = -o;
	    }
	    o = modf(o, &tmp);
	    if (!floor(tmp / CM_PERIOD)) {
		nth = INT2FIX(0);
		jd = (int)tmp;
	    }
	    else {
		double i, f;
		f = modf(tmp / CM_PERIOD, &i);
		nth = f_floor(DBL2NUM(i));
		jd = (int)(f * CM_PERIOD);
	    }
	    o *= DAY_IN_SECONDS;
	    o = modf(o, &tmp);
	    df = (int)tmp;
	    o *= SECOND_IN_NANOSECONDS;
	    sf = INT2FIX((int)round(o));
	    if (s < 0) {
		jd = -jd;
		df = -df;
		sf = f_negate(sf);
	    }
	    if (f_zero_p(sf))
		sf = m_sf(dat);
	    else {
		sf = f_add(m_sf(dat), sf);
		if (f_lt_p(sf, INT2FIX(0))) {
		    df -= 1;
		    sf = f_add(sf, INT2FIX(SECOND_IN_NANOSECONDS));
		}
		else if (f_ge_p(sf, INT2FIX(SECOND_IN_NANOSECONDS))) {
		    df += 1;
		    sf = f_sub(sf, INT2FIX(SECOND_IN_NANOSECONDS));
		}
	    }
	    if (!df)
		df = m_df(dat);
	    else {
		df = m_df(dat) + df;
		if (df < 0) {
		    jd -= 1;
		    df += DAY_IN_SECONDS;
		}
		else if (df >= DAY_IN_SECONDS) {
		    jd += 1;
		    df -= DAY_IN_SECONDS;
		}
	    }
	    if (!jd)
		jd = m_jd(dat);
	    else {
		jd = m_jd(dat) + jd;
		canonicalize_jd(nth, jd);
	    }
	    if (f_zero_p(nth))
		nth = m_nth(dat);
	    else
		nth = f_add(m_nth(dat), nth);
	    if (!df && f_zero_p(sf) && !m_of(dat))
		return d_simple_new_internal(rb_obj_class(self),
					     nth, (int)jd,
					     m_sg(dat),
					     0, 0, 0,
					     (dat->s.flags | HAVE_JD) &
					     ~(HAVE_CIVIL | HAVE_TIME |
					       COMPLEX_DAT));
	    else
		return d_complex_new_internal(rb_obj_class(self),
					      nth, (int)jd,
					      df, sf,
					      m_of(dat), m_sg(dat),
					      0, 0, 0,
					      0, 0, 0,
					      (dat->c.flags |
					       HAVE_JD | HAVE_DF) &
					      ~(HAVE_CIVIL | HAVE_TIME));
	}
	break;
      default:
	expect_numeric(other);
	other = f_to_r(other);
	if (!k_rational_p(other)) {
	    if (!try_rational) Check_Type(other, T_RATIONAL);
	    try_rational = 0;
	    goto again;
	}
	/* fall through */
      case T_RATIONAL:
	{
	    VALUE nth, sf, t;
	    int jd, df, s;
	    if (wholenum_p(other)) {
		other = rb_rational_num(other);
		goto again;
	    }
	    if (f_positive_p(other))
		s = +1;
	    else {
		s = -1;
		other = f_negate(other);
	    }
	    nth = f_idiv(other, INT2FIX(CM_PERIOD));
	    t = f_mod(other, INT2FIX(CM_PERIOD));
	    jd = FIX2INT(f_idiv(t, INT2FIX(1)));
	    t = f_mod(t, INT2FIX(1));
	    t = f_mul(t, INT2FIX(DAY_IN_SECONDS));
	    df = FIX2INT(f_idiv(t, INT2FIX(1)));
	    t = f_mod(t, INT2FIX(1));
	    sf = f_mul(t, INT2FIX(SECOND_IN_NANOSECONDS));
	    if (s < 0) {
		nth = f_negate(nth);
		jd = -jd;
		df = -df;
		sf = f_negate(sf);
	    }
	    if (f_zero_p(sf))
		sf = m_sf(dat);
	    else {
		sf = f_add(m_sf(dat), sf);
		if (f_lt_p(sf, INT2FIX(0))) {
		    df -= 1;
		    sf = f_add(sf, INT2FIX(SECOND_IN_NANOSECONDS));
		}
		else if (f_ge_p(sf, INT2FIX(SECOND_IN_NANOSECONDS))) {
		    df += 1;
		    sf = f_sub(sf, INT2FIX(SECOND_IN_NANOSECONDS));
		}
	    }
	    if (!df)
		df = m_df(dat);
	    else {
		df = m_df(dat) + df;
		if (df < 0) {
		    jd -= 1;
		    df += DAY_IN_SECONDS;
		}
		else if (df >= DAY_IN_SECONDS) {
		    jd += 1;
		    df -= DAY_IN_SECONDS;
		}
	    }
	    if (!jd)
		jd = m_jd(dat);
	    else {
		jd = m_jd(dat) + jd;
		canonicalize_jd(nth, jd);
	    }
	    if (f_zero_p(nth))
		nth = m_nth(dat);
	    else
		nth = f_add(m_nth(dat), nth);
	    if (!df && f_zero_p(sf) && !m_of(dat))
		return d_simple_new_internal(rb_obj_class(self),
					     nth, jd,
					     m_sg(dat),
					     0, 0, 0,
					     (dat->s.flags | HAVE_JD) &
					     ~(HAVE_CIVIL | HAVE_TIME |
					       COMPLEX_DAT));
	    else
		return d_complex_new_internal(rb_obj_class(self),
					      nth, jd,
					      df, sf,
					      m_of(dat), m_sg(dat),
					      0, 0, 0,
					      0, 0, 0,
					      (dat->c.flags |
					       HAVE_JD | HAVE_DF) &
					      ~(HAVE_CIVIL | HAVE_TIME));
	}
	break;
    }
}
  
    #-(other)  ⇒ Date, Rational   
If the other is a date object, returns a Rational whose value is the difference between the two dates in days. If the other is a numeric value, returns a date object pointing other days before self. If the other is a fractional number, assumes its precision is at most nanosecond.
Date.new(2001,2,3) - 1   #=> #<Date: 2001-02-02 ...>
DateTime.new(2001,2,3) - Rational(1,2)
                         #=> #<DateTime: 2001-02-02T12:00:00+00:00 ...>
Date.new(2001,2,3) - Date.new(2001)
                         #=> (33/1)
DateTime.new(2001,2,3) - DateTime.new(2001,2,2,12)
                         #=> (1/2)# File 'ext/date/date_core.c', line 6343
static VALUE
d_lite_minus(VALUE self, VALUE other)
{
    if (k_date_p(other))
	return minus_dd(self, other);
    switch (TYPE(other)) {
      case T_FIXNUM:
	return d_lite_plus(self, LONG2NUM(-FIX2LONG(other)));
      case T_FLOAT:
	return d_lite_plus(self, DBL2NUM(-RFLOAT_VALUE(other)));
      default:
	expect_numeric(other);
	/* fall through */
      case T_BIGNUM:
      case T_RATIONAL:
	return d_lite_plus(self, f_negate(other));
    }
}
  
    #<<(n)  ⇒ Date   
Returns a new Date object representing the date n months earlier; n should be a numeric:
(Date.new(2001, 2, 3) << 1).to_s  # => "2001-01-03"
(Date.new(2001, 2, 3) << -2).to_s # => "2001-04-03"When the same day does not exist for the new month, the last day of that month is used instead:
(Date.new(2001, 3, 31) << 1).to_s  # => "2001-02-28"
(Date.new(2001, 3, 31) << -6).to_s # => "2001-09-30"This results in the following, possibly unexpected, behaviors:
d0 = Date.new(2001, 3, 31)
d0 << 2      # => #<Date: 2001-01-31>
d0 << 1 << 1 # => #<Date: 2001-01-28>
d0 = Date.new(2001, 3, 31)
d1 = d0 << 1  # => #<Date: 2001-02-28>
d2 = d1 << -1 # => #<Date: 2001-03-28># File 'ext/date/date_core.c', line 6507
static VALUE
d_lite_lshift(VALUE self, VALUE other)
{
    expect_numeric(other);
    return d_lite_rshift(self, f_negate(other));
}
  
    #<=>(other)  ⇒ 1, ...   
Compares self and other, returning:
- 
-1ifotheris larger.
- 
0if the two are equal.
- 
1ifotheris smaller.
- 
nilif the two are incomparable.
Argument other may be:
- 
Another Date object: d = Date.new(2022, 7, 27) # => #<Date: 2022-07-27 ((2459788j,0s,0n),+0s,2299161j)> prev_date = d.prev_day # => #<Date: 2022-07-26 ((2459787j,0s,0n),+0s,2299161j)> next_date = d.next_day # => #<Date: 2022-07-28 ((2459789j,0s,0n),+0s,2299161j)> d <=> next_date # => -1 d <=> d # => 0 d <=> prev_date # => 1
- 
A DateTime object: d <=> DateTime.new(2022, 7, 26) # => 1 d <=> DateTime.new(2022, 7, 27) # => 0 d <=> DateTime.new(2022, 7, 28) # => -1
- 
A numeric (compares self.ajdtoother):d <=> 2459788 # => -1 d <=> 2459787 # => 1 d <=> 2459786 # => 1 d <=> d.ajd # => 0
- 
Any other object: d <=> Object.new # => nil
# File 'ext/date/date_core.c', line 6804
static VALUE
d_lite_cmp(VALUE self, VALUE other)
{
    if (!k_date_p(other))
	return cmp_gen(self, other);
    {
	get_d2(self, other);
	if (!(simple_dat_p(adat) && simple_dat_p(bdat) &&
	      m_gregorian_p(adat) == m_gregorian_p(bdat)))
	    return cmp_dd(self, other);
	{
	    VALUE a_nth, b_nth;
	    int a_jd, b_jd;
	    m_canonicalize_jd(self, adat);
	    m_canonicalize_jd(other, bdat);
	    a_nth = m_nth(adat);
	    b_nth = m_nth(bdat);
	    if (f_eqeq_p(a_nth, b_nth)) {
		a_jd = m_jd(adat);
		b_jd = m_jd(bdat);
		if (a_jd == b_jd) {
		    return INT2FIX(0);
		}
		else if (a_jd < b_jd) {
		    return INT2FIX(-1);
		}
		else {
		    return INT2FIX(1);
		}
	    }
	    else if (f_lt_p(a_nth, b_nth)) {
		return INT2FIX(-1);
	    }
	    else {
		return INT2FIX(1);
	    }
	}
    }
}
  
    #===(other)  ⇒ true, ...   
Returns true if self and other represent the same date, false if not, nil if the two are not comparable.
Argument other may be:
- 
Another Date object: d = Date.new(2022, 7, 27) # => #<Date: 2022-07-27 ((2459788j,0s,0n),+0s,2299161j)> prev_date = d.prev_day # => #<Date: 2022-07-26 ((2459787j,0s,0n),+0s,2299161j)> next_date = d.next_day # => #<Date: 2022-07-28 ((2459789j,0s,0n),+0s,2299161j)> d === prev_date # => false d === d # => true d === next_date # => false
- 
A DateTime object: d === DateTime.new(2022, 7, 26) # => false d === DateTime.new(2022, 7, 27) # => true d === DateTime.new(2022, 7, 28) # => false
- 
A numeric (compares self.jdtoother):d === 2459788 # => true d === 2459787 # => false d === 2459786 # => false d === d.jd # => true
- 
An object not comparable: d === Object.new # => nil
# File 'ext/date/date_core.c', line 6896
static VALUE
d_lite_equal(VALUE self, VALUE other)
{
    if (!k_date_p(other))
	return equal_gen(self, other);
    {
	get_d2(self, other);
	if (!(m_gregorian_p(adat) == m_gregorian_p(bdat)))
	    return equal_gen(self, other);
	{
	    VALUE a_nth, b_nth;
	    int a_jd, b_jd;
	    m_canonicalize_jd(self, adat);
	    m_canonicalize_jd(other, bdat);
	    a_nth = m_nth(adat);
	    b_nth = m_nth(bdat);
	    a_jd = m_local_jd(adat);
	    b_jd = m_local_jd(bdat);
	    if (f_eqeq_p(a_nth, b_nth) &&
		a_jd == b_jd)
		return Qtrue;
	    return Qfalse;
	}
    }
}
  
    #>>(n)  ⇒ Date   
Returns a new Date object representing the date n months later; n should be a numeric:
(Date.new(2001, 2, 3) >> 1).to_s  # => "2001-03-03"
(Date.new(2001, 2, 3) >> -2).to_s # => "2000-12-03"When the same day does not exist for the new month, the last day of that month is used instead:
(Date.new(2001, 1, 31) >> 1).to_s  # => "2001-02-28"
(Date.new(2001, 1, 31) >> -4).to_s # => "2000-09-30"This results in the following, possibly unexpected, behaviors:
d0 = Date.new(2001, 1, 31)
d1 = d0 >> 1 # => #<Date: 2001-02-28>
d2 = d1 >> 1 # => #<Date: 2001-03-28>
d0 = Date.new(2001, 1, 31)
d1 = d0 >> 1  # => #<Date: 2001-02-28>
d2 = d1 >> -1 # => #<Date: 2001-01-28># File 'ext/date/date_core.c', line 6441
static VALUE
d_lite_rshift(VALUE self, VALUE other)
{
    VALUE t, y, nth, rjd2;
    int m, d, rjd;
    double sg;
    get_d1(self);
    t = f_add3(f_mul(m_real_year(dat), INT2FIX(12)),
	       INT2FIX(m_mon(dat) - 1),
	       other);
    if (FIXNUM_P(t)) {
	long it = FIX2LONG(t);
	y = LONG2NUM(DIV(it, 12));
	it = MOD(it, 12);
	m = (int)it + 1;
    }
    else {
	y = f_idiv(t, INT2FIX(12));
	t = f_mod(t, INT2FIX(12));
	m = FIX2INT(t) + 1;
    }
    d = m_mday(dat);
    sg = m_sg(dat);
    while (1) {
	int ry, rm, rd, ns;
	if (valid_civil_p(y, m, d, sg,
			  &nth, &ry,
			  &rm, &rd, &rjd, &ns))
	    break;
	if (--d < 1)
	    rb_raise(eDateError, "invalid date");
    }
    encode_jd(nth, rjd, &rjd2);
    return d_lite_plus(self, f_sub(rjd2, m_real_local_jd(dat)));
}
  
    #ajd  ⇒ Rational   
# File 'ext/date/date_core.c', line 5214
static VALUE
d_lite_ajd(VALUE self)
{
    get_d1(self);
    return m_ajd(dat);
}
  
    #amjd  ⇒ Rational   
# File 'ext/date/date_core.c', line 5231
static VALUE
d_lite_amjd(VALUE self)
{
    get_d1(self);
    return m_amjd(dat);
}
  
    
      #ctime  ⇒ String 
      #asctime  ⇒ String 
    
  
String 
      #asctime  ⇒ String 
    Alias for #ctime.
    #ctime  ⇒ String     Also known as: #asctime
  
Equivalent to #strftime with argument '%a %b %e %T %Y' (or its shorthand form '%c'):
Date.new(2001, 2, 3).asctime # => "Sat Feb  3 00:00:00 2001"See asctime.
# File 'ext/date/date_core.c', line 7292
static VALUE
d_lite_asctime(VALUE self)
{
    return strftimev("%a %b %e %H:%M:%S %Y", self, set_tmx);
}
  
    #cwday  ⇒ Integer   
Returns the commercial-date weekday index for self (see .commercial); 1 is Monday:
Date.new(2001, 2, 3).cwday # => 6# File 'ext/date/date_core.c', line 5420
static VALUE
d_lite_cwday(VALUE self)
{
    get_d1(self);
    return INT2FIX(m_cwday(dat));
}
  
    #cweek  ⇒ Integer   
Returns commercial-date week index for self (see .commercial):
Date.new(2001, 2, 3).cweek # => 5# File 'ext/date/date_core.c', line 5402
static VALUE
d_lite_cweek(VALUE self)
{
    get_d1(self);
    return INT2FIX(m_cweek(dat));
}
  
    #cwyear  ⇒ Integer   
Returns commercial-date year for self (see .commercial):
Date.new(2001, 2, 3).cwyear # => 2001
Date.new(2000, 1, 1).cwyear # => 1999# File 'ext/date/date_core.c', line 5385
static VALUE
d_lite_cwyear(VALUE self)
{
    get_d1(self);
    return m_real_cwyear(dat);
}
  
    #day  ⇒ Integer     Also known as: #mday
  
  [ GitHub ]
# File 'ext/date/date_core.c', line 5349
static VALUE
d_lite_mday(VALUE self)
{
    get_d1(self);
    return INT2FIX(m_mday(dat));
}
  
    #day_fraction  ⇒ Rational   
# File 'ext/date/date_core.c', line 5365
static VALUE
d_lite_day_fraction(VALUE self)
{
    get_d1(self);
    if (simple_dat_p(dat))
	return INT2FIX(0);
    return m_fr(dat);
}
  
    #deconstruct_keys(array_of_names_or_nil)  ⇒ Hash   
Returns a hash of the name/value pairs, to use in pattern matching. Possible keys are: :year, :month, :day, :wday, :yday.
Possible usages:
d = Date.new(2022, 10, 5)
if d in wday: 3, day: ..7  # uses deconstruct_keys underneath
  puts "first Wednesday of the month"
end
#=> prints "first Wednesday of the month"
case d
in year: ...2022
  puts "too old"
in month: ..9
  puts "quarter 1-3"
in wday: 1..5, month:
  puts "working day in month #{month}"
end
#=> prints "working day in month 10"Note that deconstruction by pattern can also be combined with class check:
if d in Date(wday: 3, day: ..7)
  puts "first Wednesday of the month"
end# File 'ext/date/date_core.c', line 7511
static VALUE
d_lite_deconstruct_keys(VALUE self, VALUE keys)
{
    return deconstruct_keys(self, keys, /* is_datetime=false */ 0);
}
  
    #downto(min) {|date| ... } ⇒ self   
  [ GitHub ]
# File 'ext/date/date_core.c', line 6680
static VALUE
d_lite_downto(VALUE self, VALUE min)
{
    VALUE date;
    RETURN_ENUMERATOR(self, 1, &min);
    date = self;
    while (FIX2INT(d_lite_cmp(date, min)) >= 0) {
	rb_yield(date);
	date = d_lite_plus(date, INT2FIX(-1));
    }
    return self;
}
  
    #england  ⇒ Date   
Equivalent to #new_start with argument ENGLAND.
# File 'ext/date/date_core.c', line 5860
static VALUE
d_lite_england(VALUE self)
{
    return dup_obj_with_new_start(self, ENGLAND);
}
  
    #eql?(other)  ⇒ Boolean 
  
  # File 'ext/date/date_core.c', line 6927
static VALUE
d_lite_eql_p(VALUE self, VALUE other)
{
    if (!k_date_p(other))
	return Qfalse;
    return f_zero_p(d_lite_cmp(self, other));
}
  #fill
# File 'ext/date/date_core.c', line 5185
static VALUE
d_lite_fill(VALUE self)
{
    get_d1(self);
    if (simple_dat_p(dat)) {
	get_s_jd(dat);
	get_s_civil(dat);
    }
    else {
	get_c_jd(dat);
	get_c_civil(dat);
	get_c_df(dat);
	get_c_time(dat);
    }
    return self;
}
  #hash
# File 'ext/date/date_core.c', line 6936
static VALUE
d_lite_hash(VALUE self)
{
    st_index_t v, h[5];
    VALUE nth;
    get_d1(self);
    nth = m_nth(dat);
    if (FIXNUM_P(nth)) {
        h[0] = 0;
        h[1] = (st_index_t)nth;
    } else {
        h[0] = 1;
        h[1] = (st_index_t)FIX2LONG(rb_hash(nth));
    }
    h[2] = m_jd(dat);
    h[3] = m_df(dat);
    h[4] = m_sf(dat);
    v = rb_memhash(h, sizeof(h));
    return ST2FIX(v);
}
  #hour (private)
Alias for #min.
    #httpdate  ⇒ String   
Equivalent to #strftime with argument '%a, %d %b %Y %T GMT'; see Formats for Dates and Times:
Date.new(2001, 2, 3).httpdate # => "Sat, 03 Feb 2001 00:00:00 GMT"# File 'ext/date/date_core.c', line 7357
static VALUE
d_lite_httpdate(VALUE self)
{
    volatile VALUE dup = dup_obj_with_new_offset(self, 0);
    return strftimev("%a, %d %b %Y %T GMT", dup, set_tmx);
}
  #initialize_copy(date)
# File 'ext/date/date_core.c', line 5139
static VALUE
d_lite_initialize_copy(VALUE copy, VALUE date)
{
    rb_check_frozen(copy);
    if (copy == date)
	return copy;
    {
	get_d2(copy, date);
	if (simple_dat_p(bdat)) {
	    if (simple_dat_p(adat)) {
		adat->s = bdat->s;
	    }
	    else {
		adat->c.flags = bdat->s.flags | COMPLEX_DAT;
		adat->c.nth = bdat->s.nth;
		adat->c.jd = bdat->s.jd;
		adat->c.df = 0;
		adat->c.sf = INT2FIX(0);
		adat->c.of = 0;
		adat->c.sg = bdat->s.sg;
		adat->c.year = bdat->s.year;
#ifndef USE_PACK
		adat->c.mon = bdat->s.mon;
		adat->c.mday = bdat->s.mday;
		adat->c.hour = bdat->s.hour;
		adat->c.min = bdat->s.min;
		adat->c.sec = bdat->s.sec;
#else
		adat->c.pc = bdat->s.pc;
#endif
	    }
	}
	else {
	    if (!complex_dat_p(adat))
		rb_raise(rb_eArgError,
			 "cannot load complex into simple");
	    adat->c = bdat->c;
	}
    }
    return copy;
}
  
    #inspect  ⇒ String   
Returns a string representation of self:
Date.new(2001, 2, 3).inspect
# => "#<Date: 2001-02-03 ((2451944j,0s,0n),+0s,2299161j)>"# File 'ext/date/date_core.c', line 7064
static VALUE
d_lite_inspect(VALUE self)
{
    get_d1(self);
    return mk_inspect(dat, rb_obj_class(self), self);
}
  #inspect_raw
# File 'ext/date/date_core.c', line 7035
static VALUE
d_lite_inspect_raw(VALUE self)
{
    get_d1(self);
    return mk_inspect_raw(dat, rb_obj_class(self));
}
  
    #iso8601  ⇒ String     Also known as: #xmlschema
  
Equivalent to #strftime with argument '%Y-%m-%d' (or its shorthand form '%F');
Date.new(2001, 2, 3).iso8601 # => "2001-02-03"# File 'ext/date/date_core.c', line 7309
static VALUE
d_lite_iso8601(VALUE self)
{
    return strftimev("%Y-%m-%d", self, set_tmx);
}
  
    #italy  ⇒ Date   
Equivalent to #new_start with argument ITALY.
# File 'ext/date/date_core.c', line 5848
static VALUE
d_lite_italy(VALUE self)
{
    return dup_obj_with_new_start(self, ITALY);
}
  
    #jd  ⇒ Integer   
# File 'ext/date/date_core.c', line 5248
static VALUE
d_lite_jd(VALUE self)
{
    get_d1(self);
    return m_real_local_jd(dat);
}
  
    #jisx0301  ⇒ String   
# File 'ext/date/date_core.c', line 7414
static VALUE
d_lite_jisx0301(VALUE self)
{
    char fmtbuf[JISX0301_DATE_SIZE];
    const char *fmt;
    get_d1(self);
    fmt = jisx0301_date_format(fmtbuf, sizeof(fmtbuf),
			       m_real_local_jd(dat),
			       m_real_year(dat));
    return strftimev(fmt, self, set_tmx);
}
  
    #ld  ⇒ Integer   
Returns the Lilian day number, which is the number of days since the beginning of the Gregorian calendar, October 15, 1582.
Date.new(2001, 2, 3).ld # => 152784# File 'ext/date/date_core.c', line 5284
static VALUE
d_lite_ld(VALUE self)
{
    get_d1(self);
    return f_sub(m_real_local_jd(dat), INT2FIX(2299160));
}
  #marshal_dump
# File 'ext/date/date_core.c', line 7541
static VALUE
d_lite_marshal_dump(VALUE self)
{
    VALUE a;
    get_d1(self);
    a = rb_ary_new3(6,
		    m_nth(dat),
		    INT2FIX(m_jd(dat)),
		    INT2FIX(m_df(dat)),
		    m_sf(dat),
		    INT2FIX(m_of(dat)),
		    DBL2NUM(m_sg(dat)));
    if (FL_TEST(self, FL_EXIVAR)) {
	rb_copy_generic_ivar(a, self);
	FL_SET(a, FL_EXIVAR);
    }
    return a;
}
  #marshal_dump_old
# File 'ext/date/date_core.c', line 7519
static VALUE
d_lite_marshal_dump_old(VALUE self)
{
    VALUE a;
    get_d1(self);
    a = rb_ary_new3(3,
		    m_ajd(dat),
		    m_of_in_day(dat),
		    DBL2NUM(m_sg(dat)));
    if (FL_TEST(self, FL_EXIVAR)) {
	rb_copy_generic_ivar(a, self);
	FL_SET(a, FL_EXIVAR);
    }
    return a;
}
  #marshal_load(a)
# File 'ext/date/date_core.c', line 7565
static VALUE
d_lite_marshal_load(VALUE self, VALUE a)
{
    VALUE nth, sf;
    int jd, df, of;
    double sg;
    get_d1(self);
    rb_check_frozen(self);
    if (!RB_TYPE_P(a, T_ARRAY))
	rb_raise(rb_eTypeError, "expected an array");
    switch (RARRAY_LEN(a)) {
      case 2: /* 1.6.x */
      case 3: /* 1.8.x, 1.9.2 */
	{
	    VALUE ajd, vof, vsg;
	    if  (RARRAY_LEN(a) == 2) {
		ajd = f_sub(RARRAY_AREF(a, 0), half_days_in_day);
		vof = INT2FIX(0);
		vsg = RARRAY_AREF(a, 1);
		if (!k_numeric_p(vsg))
		    vsg = DBL2NUM(RTEST(vsg) ? GREGORIAN : JULIAN);
	    }
	    else {
		ajd = RARRAY_AREF(a, 0);
		vof = RARRAY_AREF(a, 1);
		vsg = RARRAY_AREF(a, 2);
	    }
	    old_to_new(ajd, vof, vsg,
		       &nth, &jd, &df, &sf, &of, &sg);
	}
	break;
      case 6:
	{
	    nth = RARRAY_AREF(a, 0);
	    jd = NUM2INT(RARRAY_AREF(a, 1));
	    df = NUM2INT(RARRAY_AREF(a, 2));
	    sf = RARRAY_AREF(a, 3);
	    of = NUM2INT(RARRAY_AREF(a, 4));
	    sg = NUM2DBL(RARRAY_AREF(a, 5));
	}
	break;
      default:
	rb_raise(rb_eTypeError, "invalid size");
	break;
    }
    if (simple_dat_p(dat)) {
	if (df || !f_zero_p(sf) || of) {
	    /* loading a fractional date; promote to complex */
	    dat = ruby_xrealloc(dat, sizeof(struct ComplexDateData));
	    RTYPEDDATA(self)->data = dat;
	    goto complex_data;
	}
	set_to_simple(self, &dat->s, nth, jd, sg, 0, 0, 0, HAVE_JD);
    } else {
      complex_data:
	set_to_complex(self, &dat->c, nth, jd, df, sf, of, sg,
		       0, 0, 0, 0, 0, 0,
		       HAVE_JD | HAVE_DF);
    }
    if (FL_TEST(a, FL_EXIVAR)) {
	rb_copy_generic_ivar(self, a);
	FL_SET(self, FL_EXIVAR);
    }
    return self;
}
  
    
      #day  ⇒ Integer 
      #mday  ⇒ Integer 
    
  
Integer 
      #mday  ⇒ Integer 
    Alias for #day.
#min (private) Also known as: #hour, #minute, #sec, #second
[ GitHub ]# File 'ext/date/date_core.c', line 9479
static VALUE
d_lite_zero(VALUE x)
{
    return INT2FIX(0);
}
  #minute (private)
Alias for #min.
    #mjd  ⇒ Integer   
# File 'ext/date/date_core.c', line 5265
static VALUE
d_lite_mjd(VALUE self)
{
    get_d1(self);
    return f_sub(m_real_local_jd(dat), INT2FIX(2400001));
}
  
    #mon  ⇒ Integer     Also known as: #month
  
Returns the month in range (1..12):
Date.new(2001, 2, 3).mon # => 2# File 'ext/date/date_core.c', line 5333
static VALUE
d_lite_mon(VALUE self)
{
    get_d1(self);
    return INT2FIX(m_mon(dat));
}
  
    
      #mon  ⇒ Integer 
      #month  ⇒ Integer 
    
  
Integer 
      #month  ⇒ Integer 
    Alias for #mon.
    #new_start(start = Date::ITALY])  ⇒ Date   
# File 'ext/date/date_core.c', line 5826
static VALUE
d_lite_new_start(int argc, VALUE *argv, VALUE self)
{
    VALUE vsg;
    double sg;
    rb_scan_args(argc, argv, "01", &vsg);
    sg = DEFAULT_SG;
    if (argc >= 1)
	val2sg(vsg, sg);
    return dup_obj_with_new_start(self, sg);
}
  
    #next  ⇒ Date     Also known as: #succ
  
# File 'ext/date/date_core.c', line 6408
static VALUE
d_lite_next(VALUE self)
{
    return d_lite_next_day(0, (VALUE *)NULL, self);
}
  
    #next_day(n = 1)  ⇒ Date   
Equivalent to #+ with argument n.
# File 'ext/date/date_core.c', line 6369
static VALUE
d_lite_next_day(int argc, VALUE *argv, VALUE self)
{
    VALUE n;
    rb_scan_args(argc, argv, "01", &n);
    if (argc < 1)
	n = INT2FIX(1);
    return d_lite_plus(self, n);
}
  
    #next_month(n = 1)  ⇒ Date   
Equivalent to #>> with argument n.
# File 'ext/date/date_core.c', line 6520
static VALUE
d_lite_next_month(int argc, VALUE *argv, VALUE self)
{
    VALUE n;
    rb_scan_args(argc, argv, "01", &n);
    if (argc < 1)
	n = INT2FIX(1);
    return d_lite_rshift(self, n);
}
  
    #next_year(n = 1)  ⇒ Date   
Equivalent to #>> with argument n * 12.
# File 'ext/date/date_core.c', line 6554
static VALUE
d_lite_next_year(int argc, VALUE *argv, VALUE self)
{
    VALUE n;
    rb_scan_args(argc, argv, "01", &n);
    if (argc < 1)
	n = INT2FIX(1);
    return d_lite_rshift(self, f_mul(n, INT2FIX(12)));
}
  
    #nth_kday?(n, k)  ⇒ Boolean 
  
  # File 'ext/date/date_core.c', line 5554
static VALUE
d_lite_nth_kday_p(VALUE self, VALUE n, VALUE k)
{
    int rjd, ns;
    get_d1(self);
    if (NUM2INT(k) != m_wday(dat))
	return Qfalse;
    c_nth_kday_to_jd(m_year(dat), m_mon(dat),
		     NUM2INT(n), NUM2INT(k), m_virtual_sg(dat), /* !=m_sg() */
		     &rjd, &ns);
    if (m_local_jd(dat) != rjd)
	return Qfalse;
    return Qtrue;
}
  
    #prev_day(n = 1)  ⇒ Date   
Equivalent to #- with argument n.
# File 'ext/date/date_core.c', line 6386
static VALUE
d_lite_prev_day(int argc, VALUE *argv, VALUE self)
{
    VALUE n;
    rb_scan_args(argc, argv, "01", &n);
    if (argc < 1)
	n = INT2FIX(1);
    return d_lite_minus(self, n);
}
  
    #prev_month(n = 1)  ⇒ Date   
Equivalent to #<< with argument n.
# File 'ext/date/date_core.c', line 6537
static VALUE
d_lite_prev_month(int argc, VALUE *argv, VALUE self)
{
    VALUE n;
    rb_scan_args(argc, argv, "01", &n);
    if (argc < 1)
	n = INT2FIX(1);
    return d_lite_lshift(self, n);
}
  
    #prev_year(n = 1)  ⇒ Date   
Equivalent to #<< with argument n * 12.
# File 'ext/date/date_core.c', line 6571
static VALUE
d_lite_prev_year(int argc, VALUE *argv, VALUE self)
{
    VALUE n;
    rb_scan_args(argc, argv, "01", &n);
    if (argc < 1)
	n = INT2FIX(1);
    return d_lite_lshift(self, f_mul(n, INT2FIX(12)));
}
  
    
      #rfc822  ⇒ String 
      #rfc2822  ⇒ String 
    
  
String 
      #rfc2822  ⇒ String 
    Alias for #rfc822.
    #rfc3339  ⇒ String   
Equivalent to #strftime with argument '%FT%T%:z'; see Formats for Dates and Times:
Date.new(2001, 2, 3).rfc3339 # => "2001-02-03T00:00:00+00:00"# File 'ext/date/date_core.c', line 7325
static VALUE
d_lite_rfc3339(VALUE self)
{
    return strftimev("%Y-%m-%dT%H:%M:%S%:z", self, set_tmx);
}
  
    #rfc822  ⇒ String     Also known as: #rfc2822
  
Equivalent to #strftime with argument '%a, %-d %b %Y %T %z'; see Formats for Dates and Times:
Date.new(2001, 2, 3).rfc2822 # => "Sat, 3 Feb 2001 00:00:00 +0000"# File 'ext/date/date_core.c', line 7341
static VALUE
d_lite_rfc2822(VALUE self)
{
    return strftimev("%a, %-d %b %Y %T %z", self, set_tmx);
}
  #sec (private)
Alias for #min.
#second (private)
Alias for #min.
    #start  ⇒ Float   
Returns the Julian start date for calendar reform; if not an infinity, the returned value is suitable for passing to #jd:
d = Date.new(2001, 2, 3, Date::ITALY)
s = d.start     # => 2299161.0
Date.jd(s).to_s # => "1582-10-15"
d = Date.new(2001, 2, 3, Date::ENGLAND)
s = d.start     # => 2361222.0
Date.jd(s).to_s # => "1752-09-14"
Date.new(2001, 2, 3, Date::GREGORIAN).start # => -Infinity
Date.new(2001, 2, 3, Date::JULIAN).start    # => InfinitySee argument start.
# File 'ext/date/date_core.c', line 5751
static VALUE
d_lite_start(VALUE self)
{
    get_d1(self);
    return DBL2NUM(m_sg(dat));
}
  
    #step(limit, step = 1) {|date| ... } ⇒ self   
Calls the block with specified dates; returns self.
- 
The first dateisself.
- 
Each successive dateisdate + step, wherestepis the numeric step size in days.
- 
The last date is the last one that is before or equal to limit, which should be a Date object.
Example:
limit = Date.new(2001, 12, 31)
Date.new(2001).step(limit){|date| p date.to_s if date.mday == 31 }Output:
"2001-01-31"
"2001-03-31"
"2001-05-31"
"2001-07-31"
"2001-08-31"
"2001-10-31"
"2001-12-31"Returns an Enumerator if no block is given.
# File 'ext/date/date_core.c', line 6614
static VALUE
d_lite_step(int argc, VALUE *argv, VALUE self)
{
    VALUE limit, step, date;
    int c;
    rb_scan_args(argc, argv, "11", &limit, &step);
    if (argc < 2)
	step = INT2FIX(1);
#if 0
    if (f_zero_p(step))
	rb_raise(rb_eArgError, "step can't be 0");
#endif
    RETURN_ENUMERATOR(self, argc, argv);
    date = self;
    c = f_cmp(step, INT2FIX(0));
    if (c < 0) {
	while (FIX2INT(d_lite_cmp(date, limit)) >= 0) {
	    rb_yield(date);
	    date = d_lite_plus(date, step);
	}
    }
    else if (c == 0) {
	while (1)
	    rb_yield(date);
    }
    else /* if (c > 0) */ {
	while (FIX2INT(d_lite_cmp(date, limit)) <= 0) {
	    rb_yield(date);
	    date = d_lite_plus(date, step);
	}
    }
    return self;
}
  
    #strftime(format = '%F')  ⇒ String   
Returns a string representation of the date in self, formatted according the given format:
Date.new(2001, 2, 3).strftime # => "2001-02-03"For other formats, see Formats for Dates and Times.
# File 'ext/date/date_core.c', line 7255
static VALUE
d_lite_strftime(int argc, VALUE *argv, VALUE self)
{
    return date_strftime_internal(argc, argv, self,
				  "%Y-%m-%d", set_tmx);
}
  
    
      #next  ⇒ Date 
      #succ  ⇒ Date 
    
  
Date 
      #succ  ⇒ Date 
    Alias for #next.
    #to_date  ⇒ self   
Returns self.
# File 'ext/date/date_core.c', line 8988
static VALUE
date_to_date(VALUE self)
{
    return self;
}
  
    #to_datetime  ⇒ Date   
# File 'ext/date/date_core.c', line 9003
static VALUE
date_to_datetime(VALUE self)
{
    get_d1a(self);
    if (simple_dat_p(adat)) {
	VALUE new = d_lite_s_alloc_simple(cDateTime);
	{
	    get_d1b(new);
	    bdat->s = adat->s;
	    return new;
	}
    }
    else {
	VALUE new = d_lite_s_alloc_complex(cDateTime);
	{
	    get_d1b(new);
	    bdat->c = adat->c;
	    bdat->c.df = 0;
	    RB_OBJ_WRITE(new, &bdat->c.sf, INT2FIX(0));
#ifndef USE_PACK
	    bdat->c.hour = 0;
	    bdat->c.min = 0;
	    bdat->c.sec = 0;
#else
	    bdat->c.pc = PACK5(EX_MON(adat->c.pc), EX_MDAY(adat->c.pc),
			       0, 0, 0);
	    bdat->c.flags |= HAVE_DF | HAVE_TIME;
#endif
	    return new;
	}
    }
}
  
    #to_s  ⇒ String   
Returns a string representation of the date in self in ISO 8601 extended date format ('%Y-%m-%d'):
Date.new(2001, 2, 3).to_s # => "2001-02-03"# File 'ext/date/date_core.c', line 6977
static VALUE
d_lite_to_s(VALUE self)
{
    return strftimev("%Y-%m-%d", self, set_tmx);
}
  #to_time ⇒ Time
# File 'ext/date/date_core.c', line 8960
static VALUE
date_to_time(VALUE self)
{
    VALUE t;
    get_d1a(self);
    if (m_julian_p(adat)) {
        VALUE g = d_lite_gregorian(self);
        get_d1b(g);
        adat = bdat;
        self = g;
    }
    t = f_local3(rb_cTime,
        m_real_year(adat),
        INT2FIX(m_mon(adat)),
        INT2FIX(m_mday(adat)));
    RB_GC_GUARD(self); /* may be the converted gregorian */
    return t;
}
  
    #upto(max) {|date| ... } ⇒ self   
Equivalent to #step with arguments max and 1.
# File 'ext/date/date_core.c', line 6659
static VALUE
d_lite_upto(VALUE self, VALUE max)
{
    VALUE date;
    RETURN_ENUMERATOR(self, 1, &max);
    date = self;
    while (FIX2INT(d_lite_cmp(date, max)) <= 0) {
	rb_yield(date);
	date = d_lite_plus(date, INT2FIX(1));
    }
    return self;
}
  
    #wday  ⇒ Integer   
Returns the day of week in range (0..6); Sunday is 0:
Date.new(2001, 2, 3).wday # => 6# File 'ext/date/date_core.c', line 5454
static VALUE
d_lite_wday(VALUE self)
{
    get_d1(self);
    return INT2FIX(m_wday(dat));
}
  #wnum0 (private)
# File 'ext/date/date_core.c', line 5429
static VALUE
d_lite_wnum0(VALUE self)
{
    get_d1(self);
    return INT2FIX(m_wnum0(dat));
}
  #wnum1 (private)
# File 'ext/date/date_core.c', line 5437
static VALUE
d_lite_wnum1(VALUE self)
{
    get_d1(self);
    return INT2FIX(m_wnum1(dat));
}
  
    
      #iso8601  ⇒ String 
      #xmlschema  ⇒ String 
    
  
String 
      #xmlschema  ⇒ String 
    Alias for #iso8601.
    #yday  ⇒ Integer   
Returns the day of the year, in range (1..366):
Date.new(2001, 2, 3).yday # => 34# File 'ext/date/date_core.c', line 5317
static VALUE
d_lite_yday(VALUE self)
{
    get_d1(self);
    return INT2FIX(m_yday(dat));
}
  
    #year  ⇒ Integer   
  [ GitHub ]
# File 'ext/date/date_core.c', line 5301
static VALUE
d_lite_year(VALUE self)
{
    get_d1(self);
    return m_real_year(dat);
}