Class Time
In: time.c
lib/date.rb
lib/rss/rss.rb
lib/time.rb
lib/yaml/rubytypes.rb
Parent: Object

Implements the extensions to the Time class that are described in the documentation for the time.rb library.

Methods

+   -   <=>   _dump   _load   asctime   at   ctime   day   dst?   eql?   friday?   getgm   getlocal   getutc   gm   gmt?   gmt_offset   gmtime   gmtoff   hash   hour   httpdate   httpdate   inspect   isdst   iso8601   local   localtime   marshal_dump   marshal_load   mday   min   mktime   mon   monday?   month   new   now   nsec   parse   rfc2822   rfc2822   rfc822   saturday?   sec   strftime   strptime   succ   sunday?   thursday?   to_a   to_date   to_datetime   to_f   to_i   to_s   to_time   to_yaml   tuesday?   tv_nsec   tv_sec   tv_usec   usec   utc   utc   utc?   utc_offset   w3cdtf   w3cdtf   wday   wednesday?   xmlschema   xmlschema   yaml_new   yday   year   zone   zone_offset  

Included Modules

Comparable

Constants

ZoneOffset = { 'UTC' => 0, # ISO 8601 'Z' => 0, # RFC 822 'UT' => 0, 'GMT' => 0, 'EST' => -5, 'EDT' => -4, 'CST' => -6, 'CDT' => -5, 'MST' => -7, 'MDT' => -6, 'PST' => -8, 'PDT' => -7, # Following definition of military zones is original one. # See RFC 1123 and RFC 2822 for the error in RFC 822. 'A' => +1, 'B' => +2, 'C' => +3, 'D' => +4, 'E' => +5, 'F' => +6, 'G' => +7, 'H' => +8, 'I' => +9, 'K' => +10, 'L' => +11, 'M' => +12, 'N' => -1, 'O' => -2, 'P' => -3, 'Q' => -4, 'R' => -5, 'S' => -6, 'T' => -7, 'U' => -8, 'V' => -9, 'W' => -10, 'X' => -11, 'Y' => -12, }
LeapYearMonthDays = [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
CommonYearMonthDays = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
MonthValue = { 'JAN' => 1, 'FEB' => 2, 'MAR' => 3, 'APR' => 4, 'MAY' => 5, 'JUN' => 6, 'JUL' => 7, 'AUG' => 8, 'SEP' => 9, 'OCT' =>10, 'NOV' =>11, 'DEC' =>12
RFC2822_DAY_NAME = [ 'Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'
RFC2822_MONTH_NAME = [ 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'

External Aliases

rfc2822 -> rfc822
xmlschema -> iso8601

Public Class methods

Unmarshal a dumped Time object.

Creates a new time object with the value given by time, the given number of seconds_with_frac, or seconds and microseconds_with_frac from the Epoch. seconds_with_frac and microseconds_with_frac can be Integer, Float, Rational, or other Numeric. non-portable feature allows the offset to be negative on some systems.

   Time.at(0)            #=> 1969-12-31 18:00:00 -0600
   Time.at(Time.at(0))   #=> 1969-12-31 18:00:00 -0600
   Time.at(946702800)    #=> 1999-12-31 23:00:00 -0600
   Time.at(-284061600)   #=> 1960-12-31 00:00:00 -0600
   Time.at(946684800.2).usec #=> 200000
   Time.at(946684800, 123456.789).nsec #=> 123456789

Creates a time based on given values, interpreted as UTC (GMT). The year must be specified. Other values default to the minimum value for that field (and may be nil or omitted). Months may be specified by numbers from 1 to 12, or by the three-letter English month names. Hours are specified on a 24-hour clock (0..23). Raises an ArgumentError if any values are out of range. Will also accept ten arguments in the order output by Time#to_a. sec_with_frac and usec_with_frac can have a fractional part.

   Time.utc(2000,"jan",1,20,15,1)  #=> 2000-01-01 20:15:01 UTC
   Time.gm(2000,"jan",1,20,15,1)   #=> 2000-01-01 20:15:01 UTC

Parses date as HTTP-date defined by RFC 2616 and converts it to a Time object.

ArgumentError is raised if date is not compliant with RFC 2616 or Time class cannot represent specified date.

See httpdate for more information on this format.

Returns a Time object initialized to the current system time. Note: The object created will be created using the resolution available on your system clock, and so may include fractional seconds.

   a = Time.new      #=> 2007-11-19 07:50:02 -0600
   b = Time.new      #=> 2007-11-19 07:50:02 -0600
   a == b            #=> false
   "%.6f" % a.to_f   #=> "1195480202.282373"
   "%.6f" % b.to_f   #=> "1195480202.283415"
now(...)

Synonym for Time.new. Returns a Time object initialized to the current system time.

Parses date using Date._parse and converts it to a Time object.

If a block is given, the year described in date is converted by the block. For example:

    Time.parse(...) {|y| y < 100 ? (y >= 69 ? y + 1900 : y + 2000) : y}

If the upper components of the given time are broken or missing, they are supplied with those of now. For the lower components, the minimum values (1 or 0) are assumed if broken or missing. For example:

    # Suppose it is "Thu Nov 29 14:33:20 GMT 2001" now and
    # your timezone is GMT:
    Time.parse("16:30")     #=> Thu Nov 29 16:30:00 GMT 2001
    Time.parse("7/23")      #=> Mon Jul 23 00:00:00 GMT 2001
    Time.parse("Aug 31")    #=> Fri Aug 31 00:00:00 GMT 2001

Since there are numerous conflicts among locally defined timezone abbreviations all over the world, this method is not made to understand all of them. For example, the abbreviation "CST" is used variously as:

    -06:00 in America/Chicago,
    -05:00 in America/Havana,
    +08:00 in Asia/Harbin,
    +09:30 in Australia/Darwin,
    +10:30 in Australia/Adelaide,
    etc.

Based on the fact, this method only understands the timezone abbreviations described in RFC 822 and the system timezone, in the order named. (i.e. a definition in RFC 822 overrides the system timezone definition.) The system timezone is taken from Time.local(year, 1, 1).zone and Time.local(year, 7, 1).zone. If the extracted timezone abbreviation does not match any of them, it is ignored and the given time is regarded as a local time.

ArgumentError is raised if Date._parse cannot extract information from date or Time class cannot represent specified date.

This method can be used as fail-safe for other parsing methods as:

  Time.rfc2822(date) rescue Time.parse(date)
  Time.httpdate(date) rescue Time.parse(date)
  Time.xmlschema(date) rescue Time.parse(date)

A failure for Time.parse should be checked, though.

Parses date as date-time defined by RFC 2822 and converts it to a Time object. The format is identical to the date format defined by RFC 822 and updated by RFC 1123.

ArgumentError is raised if date is not compliant with RFC 2822 or Time class cannot represent specified date.

See rfc2822 for more information on this format.

Parses date using Date._strptime and converts it to a Time object.

If a block is given, the year described in date is converted by the block. For example:

    Time.strptime(...) {|y| y < 100 ? (y >= 69 ? y + 1900 : y + 2000) : y}

Creates a time based on given values, interpreted as UTC (GMT). The year must be specified. Other values default to the minimum value for that field (and may be nil or omitted). Months may be specified by numbers from 1 to 12, or by the three-letter English month names. Hours are specified on a 24-hour clock (0..23). Raises an ArgumentError if any values are out of range. Will also accept ten arguments in the order output by Time#to_a. sec_with_frac and usec_with_frac can have a fractional part.

   Time.utc(2000,"jan",1,20,15,1)  #=> 2000-01-01 20:15:01 UTC
   Time.gm(2000,"jan",1,20,15,1)   #=> 2000-01-01 20:15:01 UTC

Parses date as dateTime defined by XML Schema and converts it to a Time object. The format is restricted version of the format defined by ISO 8601.

ArgumentError is raised if date is not compliant with the format or Time class cannot represent specified date.

See xmlschema for more information on this format.

Public Instance methods

Addition—Adds some number of seconds (possibly fractional) to time and returns that value as a new time.

   t = Time.now         #=> 2007-11-19 08:22:21 -0600
   t + (60 * 60 * 24)   #=> 2007-11-20 08:22:21 -0600

Difference—Returns a new time that represents the difference between two times, or subtracts the given number of seconds in numeric from time.

   t = Time.now       #=> 2007-11-19 08:23:10 -0600
   t2 = t + 2592000   #=> 2007-12-19 08:23:10 -0600
   t2 - t             #=> 2592000.0
   t2 - 2592000       #=> 2007-11-19 08:23:10 -0600

Comparison—Compares time with other_time.

   t = Time.now       #=> 2007-11-19 08:12:12 -0600
   t2 = t + 2592000   #=> 2007-12-19 08:12:12 -0600
   t <=> t2           #=> -1
   t2 <=> t           #=> 1

   t = Time.now       #=> 2007-11-19 08:13:38 -0600
   t2 = t + 0.1       #=> 2007-11-19 08:13:38 -0600
   t.nsec             #=> 98222999
   t2.nsec            #=> 198222999
   t <=> t2           #=> -1
   t2 <=> t           #=> 1
   t <=> t            #=> 0

Dump time for marshaling.

Returns a canonical string representation of time.

   Time.now.asctime   #=> "Wed Apr  9 08:56:03 2003"

Returns a canonical string representation of time.

   Time.now.asctime   #=> "Wed Apr  9 08:56:03 2003"

Returns the day of the month (1..n) for time.

   t = Time.now   #=> 2007-11-19 08:27:03 -0600
   t.day          #=> 19
   t.mday         #=> 19

Returns true if time occurs during Daylight Saving Time in its time zone.

 # CST6CDT:
   Time.local(2000, 1, 1).zone    #=> "CST"
   Time.local(2000, 1, 1).isdst   #=> false
   Time.local(2000, 1, 1).dst?    #=> false
   Time.local(2000, 7, 1).zone    #=> "CDT"
   Time.local(2000, 7, 1).isdst   #=> true
   Time.local(2000, 7, 1).dst?    #=> true

 # Asia/Tokyo:
   Time.local(2000, 1, 1).zone    #=> "JST"
   Time.local(2000, 1, 1).isdst   #=> false
   Time.local(2000, 1, 1).dst?    #=> false
   Time.local(2000, 7, 1).zone    #=> "JST"
   Time.local(2000, 7, 1).isdst   #=> false
   Time.local(2000, 7, 1).dst?    #=> false

Return true if time and other_time are both Time objects with the same seconds and fractional seconds.

Returns true if time represents Friday.

   t = Time.local(1987, 12, 18)     #=> 1987-12-18 00:00:00 -0600
   t.friday?                        #=> true

Returns a new new_time object representing time in UTC.

   t = Time.local(2000,1,1,20,15,1)   #=> 2000-01-01 20:15:01 -0600
   t.gmt?                             #=> false
   y = t.getgm                        #=> 2000-01-02 02:15:01 UTC
   y.gmt?                             #=> true
   t == y                             #=> true

Returns a new new_time object representing time in local time (using the local time zone in effect for this process).

   t = Time.gm(2000,1,1,20,15,1)   #=> 2000-01-01 20:15:01 UTC
   t.gmt?                          #=> true
   l = t.getlocal                  #=> 2000-01-01 14:15:01 -0600
   l.gmt?                          #=> false
   t == l                          #=> true

Returns a new new_time object representing time in UTC.

   t = Time.local(2000,1,1,20,15,1)   #=> 2000-01-01 20:15:01 -0600
   t.gmt?                             #=> false
   y = t.getgm                        #=> 2000-01-02 02:15:01 UTC
   y.gmt?                             #=> true
   t == y                             #=> true

Returns true if time represents a time in UTC (GMT).

   t = Time.now                        #=> 2007-11-19 08:15:23 -0600
   t.utc?                              #=> false
   t = Time.gm(2000,"jan",1,20,15,1)   #=> 2000-01-01 20:15:01 UTC
   t.utc?                              #=> true

   t = Time.now                        #=> 2007-11-19 08:16:03 -0600
   t.gmt?                              #=> false
   t = Time.gm(2000,1,1,20,15,1)       #=> 2000-01-01 20:15:01 UTC
   t.gmt?                              #=> true

Returns the offset in seconds between the timezone of time and UTC.

   t = Time.gm(2000,1,1,20,15,1)   #=> 2000-01-01 20:15:01 UTC
   t.gmt_offset                    #=> 0
   l = t.getlocal                  #=> 2000-01-01 14:15:01 -0600
   l.gmt_offset                    #=> -21600

Converts time to UTC (GMT), modifying the receiver.

   t = Time.now   #=> 2007-11-19 08:18:31 -0600
   t.gmt?         #=> false
   t.gmtime       #=> 2007-11-19 14:18:31 UTC
   t.gmt?         #=> true

   t = Time.now   #=> 2007-11-19 08:18:51 -0600
   t.utc?         #=> false
   t.utc          #=> 2007-11-19 14:18:51 UTC
   t.utc?         #=> true

Returns the offset in seconds between the timezone of time and UTC.

   t = Time.gm(2000,1,1,20,15,1)   #=> 2000-01-01 20:15:01 UTC
   t.gmt_offset                    #=> 0
   l = t.getlocal                  #=> 2000-01-01 14:15:01 -0600
   l.gmt_offset                    #=> -21600

Return a hash code for this time object.

Returns the hour of the day (0..23) for time.

   t = Time.now   #=> 2007-11-19 08:26:20 -0600
   t.hour         #=> 8

Returns a string which represents the time as rfc1123-date of HTTP-date defined by RFC 2616:

  day-of-week, DD month-name CCYY hh:mm:ss GMT

Note that the result is always UTC (GMT).

Returns a string representing time. Equivalent to calling Time#strftime with a format string of ``%Y-%m-%d %H:%M:%S %z’’ for a local time and ``%Y-%m-%d %H:%M:%S UTC’’ for a UTC time.

   Time.now.to_s       #=> "2007-10-05 16:09:51 +0900"
   Time.now.utc.to_s   #=> "2007-10-05 07:09:51 UTC"

Returns true if time occurs during Daylight Saving Time in its time zone.

 # CST6CDT:
   Time.local(2000, 1, 1).zone    #=> "CST"
   Time.local(2000, 1, 1).isdst   #=> false
   Time.local(2000, 1, 1).dst?    #=> false
   Time.local(2000, 7, 1).zone    #=> "CDT"
   Time.local(2000, 7, 1).isdst   #=> true
   Time.local(2000, 7, 1).dst?    #=> true

 # Asia/Tokyo:
   Time.local(2000, 1, 1).zone    #=> "JST"
   Time.local(2000, 1, 1).isdst   #=> false
   Time.local(2000, 1, 1).dst?    #=> false
   Time.local(2000, 7, 1).zone    #=> "JST"
   Time.local(2000, 7, 1).isdst   #=> false
   Time.local(2000, 7, 1).dst?    #=> false
iso8601(fraction_digits=0)

Alias for xmlschema

Converts time to local time (using the local time zone in effect for this process) modifying the receiver.

   t = Time.gm(2000, "jan", 1, 20, 15, 1)  #=> 2000-01-01 20:15:01 UTC
   t.gmt?                                  #=> true
   t.localtime                             #=> 2000-01-01 14:15:01 -0600
   t.gmt?                                  #=> false

undocumented

undocumented

Returns the day of the month (1..n) for time.

   t = Time.now   #=> 2007-11-19 08:27:03 -0600
   t.day          #=> 19
   t.mday         #=> 19

Returns the minute of the hour (0..59) for time.

   t = Time.now   #=> 2007-11-19 08:25:51 -0600
   t.min          #=> 25

Returns the month of the year (1..12) for time.

   t = Time.now   #=> 2007-11-19 08:27:30 -0600
   t.mon          #=> 11
   t.month        #=> 11

Returns true if time represents Monday.

   t = Time.local(2003, 8, 4)       #=> 2003-08-04 00:00:00 -0500
   p t.monday?                      #=> true

Returns the month of the year (1..12) for time.

   t = Time.now   #=> 2007-11-19 08:27:30 -0600
   t.mon          #=> 11
   t.month        #=> 11

Returns just the number of nanoseconds for time.

   t = Time.now        #=> 2007-11-17 15:18:03 +0900
   "%10.9f" % t.to_f   #=> "1195280283.536151409"
   t.nsec              #=> 536151406

The lowest digit of to_f and nsec is different because IEEE 754 double is not accurate enough to represent nanoseconds from the Epoch. The accurate value is returned by nsec.

Returns a string which represents the time as date-time defined by RFC 2822:

  day-of-week, DD month-name CCYY hh:mm:ss zone

where zone is [+-]hhmm.

If self is a UTC time, -0000 is used as zone.

rfc822()

Alias for rfc2822

Returns true if time represents Saturday.

   t = Time.local(2006, 6, 10)      #=> 2006-06-10 00:00:00 -0500
   t.saturday?                      #=> true

Returns the second of the minute (0..60)[Yes, seconds really can range from zero to 60. This allows the system to inject leap seconds every now and then to correct for the fact that years are not really a convenient number of hours long.] for time.

   t = Time.now   #=> 2007-11-19 08:25:02 -0600
   t.sec          #=> 2

Formats time according to the directives in the given format string. Any text not listed as a directive will be passed through to the output string.

Format meaning:

  %a - The abbreviated weekday name (``Sun'')
  %A - The  full  weekday  name (``Sunday'')
  %b - The abbreviated month name (``Jan'')
  %B - The  full  month  name (``January'')
  %c - The preferred local date and time representation
  %d - Day of the month (01..31)
  %H - Hour of the day, 24-hour clock (00..23)
  %I - Hour of the day, 12-hour clock (01..12)
  %j - Day of the year (001..366)
  %m - Month of the year (01..12)
  %M - Minute of the hour (00..59)
  %p - Meridian indicator (``AM''  or  ``PM'')
  %S - Second of the minute (00..60)
  %U - Week  number  of the current year,
          starting with the first Sunday as the first
          day of the first week (00..53)
  %W - Week  number  of the current year,
          starting with the first Monday as the first
          day of the first week (00..53)
  %w - Day of the week (Sunday is 0, 0..6)
  %x - Preferred representation for the date alone, no time
  %X - Preferred representation for the time alone, no date
  %y - Year without a century (00..99)
  %Y - Year with century
  %Z - Time zone name
  %% - Literal ``%'' character

   t = Time.now                        #=> 2007-11-19 08:37:48 -0600
   t.strftime("Printed on %m/%d/%Y")   #=> "Printed on 11/19/2007"
   t.strftime("at %I:%M%p")            #=> "at 08:37AM"

Return a new time object, one second later than time.

    t = Time.now       #=> 2007-11-19 08:23:57 -0600
    t.succ             #=> 2007-11-19 08:23:58 -0600

Returns true if time represents Sunday.

   t = Time.local(1990, 4, 1)       #=> 1990-04-01 00:00:00 -0600
   t.sunday?                        #=> true

Returns true if time represents Thursday.

   t = Time.local(1995, 12, 21)     #=> 1995-12-21 00:00:00 -0600
   p t.thursday?                    #=> true

Returns a ten-element array of values for time: {[ sec, min, hour, day, month, year, wday, yday, isdst, zone ]}. See the individual methods for an explanation of the valid ranges of each value. The ten elements can be passed directly to Time::utc or Time::local to create a new Time.

   t = Time.now     #=> 2007-11-19 08:36:01 -0600
   now = t.to_a     #=> [1, 36, 8, 19, 11, 2007, 1, 323, false, "CST"]

Returns the value of time as a floating point number of seconds since the Epoch.

   t = Time.now
   "%10.5f" % t.to_f   #=> "1049896564.13654"
   t.to_i              #=> 1049896564

Note that IEEE 754 double is not accurate enough to represent nanoseconds from the Epoch.

Returns the value of time as an integer number of seconds since the Epoch.

   t = Time.now
   "%10.5f" % t.to_f   #=> "1049896564.17839"
   t.to_i              #=> 1049896564

Returns a string representing time. Equivalent to calling Time#strftime with a format string of ``%Y-%m-%d %H:%M:%S %z’’ for a local time and ``%Y-%m-%d %H:%M:%S UTC’’ for a UTC time.

   Time.now.to_s       #=> "2007-10-05 16:09:51 +0900"
   Time.now.utc.to_s   #=> "2007-10-05 07:09:51 UTC"

Returns true if time represents Tuesday.

   t = Time.local(1991, 2, 19)      #=> 1991-02-19 00:00:00 -0600
   p t.tuesday?                     #=> true

Returns just the number of nanoseconds for time.

   t = Time.now        #=> 2007-11-17 15:18:03 +0900
   "%10.9f" % t.to_f   #=> "1195280283.536151409"
   t.nsec              #=> 536151406

The lowest digit of to_f and nsec is different because IEEE 754 double is not accurate enough to represent nanoseconds from the Epoch. The accurate value is returned by nsec.

Returns the value of time as an integer number of seconds since the Epoch.

   t = Time.now
   "%10.5f" % t.to_f   #=> "1049896564.17839"
   t.to_i              #=> 1049896564

Returns just the number of microseconds for time.

   t = Time.now        #=> 2007-11-19 08:03:26 -0600
   "%10.6f" % t.to_f   #=> "1195481006.775195"
   t.usec              #=> 775195

Returns just the number of microseconds for time.

   t = Time.now        #=> 2007-11-19 08:03:26 -0600
   "%10.6f" % t.to_f   #=> "1195481006.775195"
   t.usec              #=> 775195

Converts time to UTC (GMT), modifying the receiver.

   t = Time.now   #=> 2007-11-19 08:18:31 -0600
   t.gmt?         #=> false
   t.gmtime       #=> 2007-11-19 14:18:31 UTC
   t.gmt?         #=> true

   t = Time.now   #=> 2007-11-19 08:18:51 -0600
   t.utc?         #=> false
   t.utc          #=> 2007-11-19 14:18:51 UTC
   t.utc?         #=> true

Returns true if time represents a time in UTC (GMT).

   t = Time.now                        #=> 2007-11-19 08:15:23 -0600
   t.utc?                              #=> false
   t = Time.gm(2000,"jan",1,20,15,1)   #=> 2000-01-01 20:15:01 UTC
   t.utc?                              #=> true

   t = Time.now                        #=> 2007-11-19 08:16:03 -0600
   t.gmt?                              #=> false
   t = Time.gm(2000,1,1,20,15,1)       #=> 2000-01-01 20:15:01 UTC
   t.gmt?                              #=> true

Returns the offset in seconds between the timezone of time and UTC.

   t = Time.gm(2000,1,1,20,15,1)   #=> 2000-01-01 20:15:01 UTC
   t.gmt_offset                    #=> 0
   l = t.getlocal                  #=> 2000-01-01 14:15:01 -0600
   l.gmt_offset                    #=> -21600

Returns an integer representing the day of the week, 0..6, with Sunday == 0.

   t = Time.now   #=> 2007-11-20 02:35:35 -0600
   t.wday         #=> 2
   t.sunday?      #=> false
   t.monday?      #=> false
   t.tuesday?     #=> true
   t.wednesday?   #=> false
   t.thursday?    #=> false
   t.friday?      #=> false
   t.saturday?    #=> false

Returns true if time represents Wednesday.

   t = Time.local(1993, 2, 24)      #=> 1993-02-24 00:00:00 -0600
   p t.wednesday?                   #=> true

Returns a string which represents the time as dateTime defined by XML Schema:

  CCYY-MM-DDThh:mm:ssTZD
  CCYY-MM-DDThh:mm:ss.sssTZD

where TZD is Z or [+-]hh:mm.

If self is a UTC time, Z is used as TZD. [+-]hh:mm is used otherwise.

fractional_seconds specifies a number of digits of fractional seconds. Its default value is 0.

Returns an integer representing the day of the year, 1..366.

   t = Time.now   #=> 2007-11-19 08:32:31 -0600
   t.yday         #=> 323

Returns the year for time (including the century).

   t = Time.now   #=> 2007-11-19 08:27:51 -0600
   t.year         #=> 2007

Returns the name of the time zone used for time. As of Ruby 1.8, returns ``UTC’’ rather than ``GMT’’ for UTC times.

   t = Time.gm(2000, "jan", 1, 20, 15, 1)
   t.zone   #=> "UTC"
   t = Time.local(2000, "jan", 1, 20, 15, 1)
   t.zone   #=> "CST"

[Validate]

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