Class: Date

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.

Methods

+ - << <=> === >> _dump _load _parse _strptime ajd ajd_to_amjd ajd_to_jd amjd amjd_to_ajd asctime civil civil_to_jd commercial commercial_to_jd ctime cwday cweek cwyear day day_fraction day_fraction_to_time downto england eql? gregorian gregorian_leap? hash inspect italy jd jd jd_to_ajd jd_to_civil jd_to_commercial jd_to_ld jd_to_mjd jd_to_ordinal jd_to_wday julian julian_leap? ld ld_to_jd leap? leap? mday mjd mjd_to_jd mon month new new new_start next ns? ns? ordinal ordinal_to_jd os? os? parse start step strftime strptime succ time_to_day_fraction to_s today upto valid_civil? valid_commercial? valid_date? valid_jd? valid_ordinal? wday yday year zone_to_diff

Constants

 [nil] + %w(January February March April May June July
                           August September October November December)
 %w(Sunday Monday Tuesday Wednesday Thursday Friday Saturday)
 [nil] + %w(Jan Feb Mar Apr May Jun
                                Jul Aug Sep Oct Nov Dec)
 %w(Sun Mon Tue Wed Thu Fri Sat)
 2299161
 2361222
 false
 true
 {
     'january'  => 1, 'february' => 2, 'march'    => 3, 'april'    => 4,
     'may'      => 5, 'june'     => 6, 'july'     => 7, 'august'   => 8,
     'september'=> 9, 'october'  =>10, 'november' =>11, 'december' =>12
 {
     'sunday'   => 0, 'monday'   => 1, 'tuesday'  => 2, 'wednesday'=> 3,
     'thursday' => 4, 'friday'   => 5, 'saturday' => 6
 {
     'jan'      => 1, 'feb'      => 2, 'mar'      => 3, 'apr'      => 4,
     'may'      => 5, 'jun'      => 6, 'jul'      => 7, 'aug'      => 8,
     'sep'      => 9, 'oct'      =>10, 'nov'      =>11, 'dec'      =>12
 {
     'sun'      => 0, 'mon'      => 1, 'tue'      => 2, 'wed'      => 3,
     'thu'      => 4, 'fri'      => 5, 'sat'      => 6
 {
     'ut'  =>  0*3600, 'gmt' =>  0*3600, 'est' => -5*3600, 'edt' => -4*3600,
     'cst' => -6*3600, 'cdt' => -5*3600, 'mst' => -7*3600, 'mdt' => -6*3600,
     'pst' => -8*3600, 'pdt' => -7*3600,
     'a'   =>  1*3600, 'b'   =>  2*3600, 'c'   =>  3*3600, 'd'   =>  4*3600,
     'e'   =>  5*3600, 'f'   =>  6*3600, 'g'   =>  7*3600, 'h'   =>  8*3600,
     'i'   =>  9*3600, 'k'   => 10*3600, 'l'   => 11*3600, 'm'   => 12*3600,
     'n'   => -1*3600, 'o'   => -2*3600, 'p'   => -3*3600, 'q'   => -4*3600,
     'r'   => -5*3600, 's'   => -6*3600, 't'   => -7*3600, 'u'   => -8*3600,
     'v'   => -9*3600, 'w'   =>-10*3600, 'x'   =>-11*3600, 'y'   =>-12*3600,
     'z'   =>  0*3600,
     'utc' =>  0*3600, 'wet' =>  0*3600, 'bst' =>  1*3600, 'wat' => -1*3600,
     'at'  => -2*3600, 'ast' => -4*3600, 'adt' => -3*3600, 'yst' => -9*3600,
     'ydt' => -8*3600, 'hst' =>-10*3600, 'hdt' => -9*3600, 'cat' =>-10*3600,
     'ahst'=>-10*3600, 'nt'  =>-11*3600, 'idlw'=>-12*3600, 'cet' =>  1*3600,
     'met' =>  1*3600, 'mewt'=>  1*3600, 'mest'=>  2*3600, 'mesz'=>  2*3600,
     'swt' =>  1*3600, 'sst' =>  2*3600, 'fwt' =>  1*3600, 'fst' =>  2*3600,
     'eet' =>  2*3600, 'bt'  =>  3*3600, 'zp4' =>  4*3600, 'zp5' =>  5*3600,
     'zp6' =>  6*3600, 'wast'=>  7*3600, 'wadt'=>  8*3600, 'cct' =>  8*3600,
     'jst' =>  9*3600, 'east'=> 10*3600, 'eadt'=> 11*3600, 'gst' => 10*3600,
     'nzt' => 12*3600, 'nzst'=> 12*3600, 'nzdt'=> 13*3600, 'idle'=> 12*3600
 ABBR_MONTHS.keys.join('|')
 ABBR_DAYS.  keys.join('|')

External Aliases

new -> new0

Included Modules

Comparable

Public Class methods

_load(str)

Load from Marshall format.

Date (Class)

Methods

Constants

External Aliases

Included Modules

Public Class methods

Public Instance methods

Date ^(Class)