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diff --git a/doc/strftime_formatting.rdoc b/doc/strftime_formatting.rdoc deleted file mode 100644 index 30a629bf68..0000000000 --- a/doc/strftime_formatting.rdoc +++ /dev/null @@ -1,527 +0,0 @@ -== Formats for Dates and Times - -Several Ruby time-related classes have instance method +strftime+, -which returns a formatted string representing all or part of a date or time: - -- Date#strftime. -- DateTime#strftime. -- Time#strftime. - -Each of these methods takes optional argument +format+, -which has zero or more embedded _format_ _specifications_ (see below). - -Each of these methods returns the string resulting from replacing each -format specification embedded in +format+ with a string form -of one or more parts of the date or time. - -A simple example: - - Time.now.strftime('%H:%M:%S') # => "14:02:07" - -A format specification has the form: - - %[flags][width]conversion - -It consists of: - -- A leading percent character. -- Zero or more _flags_ (each is a character). -- An optional _width_ _specifier_ (an integer). -- A _conversion_ _specifier_ (a character). - -Except for the leading percent character, -the only required part is the conversion specifier, so we begin with that. - -=== Conversion Specifiers - -==== \Date (Year, Month, Day) - -- <tt>%Y</tt> - Year including century, zero-padded: - - Time.now.strftime('%Y') # => "2022" - Time.new(-1000).strftime('%Y') # => "-1000" # Before common era. - Time.new(10000).strftime('%Y') # => "10000" # Far future. - Time.new(10).strftime('%Y') # => "0010" # Zero-padded by default. - -- <tt>%y</tt> - Year without century, in range (0.99), zero-padded: - - Time.now.strftime('%y') # => "22" - Time.new(1).strftime('%y') # => "01" # Zero-padded by default. - -- <tt>%C</tt> - Century, zero-padded: - - Time.now.strftime('%C') # => "20" - Time.new(-1000).strftime('%C') # => "-10" # Before common era. - Time.new(10000).strftime('%C') # => "100" # Far future. - Time.new(100).strftime('%C') # => "01" # Zero-padded by default. - -- <tt>%m</tt> - Month of the year, in range (1..12), zero-padded: - - Time.new(2022, 1).strftime('%m') # => "01" # Zero-padded by default. - Time.new(2022, 12).strftime('%m') # => "12" - -- <tt>%B</tt> - Full month name, capitalized: - - Time.new(2022, 1).strftime('%B') # => "January" - Time.new(2022, 12).strftime('%B') # => "December" - -- <tt>%b</tt> - Abbreviated month name, capitalized: - - Time.new(2022, 1).strftime('%b') # => "Jan" - Time.new(2022, 12).strftime('%h') # => "Dec" - -- <tt>%h</tt> - Same as <tt>%b</tt>. - -- <tt>%d</tt> - Day of the month, in range (1..31), zero-padded: - - Time.new(2002, 1, 1).strftime('%d') # => "01" - Time.new(2002, 1, 31).strftime('%d') # => "31" - -- <tt>%e</tt> - Day of the month, in range (1..31), blank-padded: - - Time.new(2002, 1, 1).strftime('%e') # => " 1" - Time.new(2002, 1, 31).strftime('%e') # => "31" - -- <tt>%j</tt> - Day of the year, in range (1..366), zero-padded: - - Time.new(2002, 1, 1).strftime('%j') # => "001" - Time.new(2002, 12, 31).strftime('%j') # => "365" - -==== \Time (Hour, Minute, Second, Subsecond) - -- <tt>%H</tt> - Hour of the day, in range (0..23), zero-padded: - - Time.new(2022, 1, 1, 1).strftime('%H') # => "01" - Time.new(2022, 1, 1, 13).strftime('%H') # => "13" - -- <tt>%k</tt> - Hour of the day, in range (0..23), blank-padded: - - Time.new(2022, 1, 1, 1).strftime('%k') # => " 1" - Time.new(2022, 1, 1, 13).strftime('%k') # => "13" - -- <tt>%I</tt> - Hour of the day, in range (1..12), zero-padded: - - Time.new(2022, 1, 1, 1).strftime('%I') # => "01" - Time.new(2022, 1, 1, 13).strftime('%I') # => "01" - -- <tt>%l</tt> - Hour of the day, in range (1..12), blank-padded: - - Time.new(2022, 1, 1, 1).strftime('%l') # => " 1" - Time.new(2022, 1, 1, 13).strftime('%l') # => " 1" - -- <tt>%P</tt> - Meridian indicator, lowercase: - - Time.new(2022, 1, 1, 1).strftime('%P') # => "am" - Time.new(2022, 1, 1, 13).strftime('%P') # => "pm" - -- <tt>%p</tt> - Meridian indicator, uppercase: - - Time.new(2022, 1, 1, 1).strftime('%p') # => "AM" - Time.new(2022, 1, 1, 13).strftime('%p') # => "PM" - -- <tt>%M</tt> - Minute of the hour, in range (0..59), zero-padded: - - Time.new(2022, 1, 1, 1, 0, 0).strftime('%M') # => "00" - -- <tt>%S</tt> - Second of the minute in range (0..59), zero-padded: - - Time.new(2022, 1, 1, 1, 0, 0, 0).strftime('%S') # => "00" - -- <tt>%L</tt> - Millisecond of the second, in range (0..999), zero-padded: - - Time.new(2022, 1, 1, 1, 0, 0, 0).strftime('%L') # => "000" - -- <tt>%N</tt> - Fractional seconds, default width is 9 digits (nanoseconds): - - t = Time.now # => 2022-06-29 07:10:20.3230914 -0500 - t.strftime('%N') # => "323091400" # Default. - - Use {width specifiers}[rdoc-ref:strftime_formatting.rdoc@Width+Specifiers] - to adjust units: - - t.strftime('%3N') # => "323" # Milliseconds. - t.strftime('%6N') # => "323091" # Microseconds. - t.strftime('%9N') # => "323091400" # Nanoseconds. - t.strftime('%12N') # => "323091400000" # Picoseconds. - t.strftime('%15N') # => "323091400000000" # Femptoseconds. - t.strftime('%18N') # => "323091400000000000" # Attoseconds. - t.strftime('%21N') # => "323091400000000000000" # Zeptoseconds. - t.strftime('%24N') # => "323091400000000000000000" # Yoctoseconds. - -- <tt>%s</tt> - Number of seconds since the epoch: - - Time.now.strftime('%s') # => "1656505136" - -==== Timezone - -- <tt>%z</tt> - Timezone as hour and minute offset from UTC: - - Time.now.strftime('%z') # => "-0500" - -- <tt>%Z</tt> - Timezone name (platform-dependent): - - Time.now.strftime('%Z') # => "Central Daylight Time" - -==== Weekday - -- <tt>%A</tt> - Full weekday name: - - Time.now.strftime('%A') # => "Wednesday" - -- <tt>%a</tt> - Abbreviated weekday name: - - Time.now.strftime('%a') # => "Wed" - -- <tt>%u</tt> - Day of the week, in range (1..7), Monday is 1: - - t = Time.new(2022, 6, 26) # => 2022-06-26 00:00:00 -0500 - t.strftime('%a') # => "Sun" - t.strftime('%u') # => "7" - -- <tt>%w</tt> - Day of the week, in range (0..6), Sunday is 0: - - t = Time.new(2022, 6, 26) # => 2022-06-26 00:00:00 -0500 - t.strftime('%a') # => "Sun" - t.strftime('%w') # => "0" - -==== Week Number - -- <tt>%U</tt> - Week number of the year, in range (0..53), zero-padded, - where each week begins on a Sunday: - - t = Time.new(2022, 6, 26) # => 2022-06-26 00:00:00 -0500 - t.strftime('%a') # => "Sun" - t.strftime('%U') # => "26" - -- <tt>%W</tt> - Week number of the year, in range (0..53), zero-padded, - where each week begins on a Monday: - - t = Time.new(2022, 6, 26) # => 2022-06-26 00:00:00 -0500 - t.strftime('%a') # => "Sun" - t.strftime('%W') # => "25" - -==== Week Dates - -See {ISO 8601 week dates}[https://en.wikipedia.org/wiki/ISO_8601#Week_dates]. - - t0 = Time.new(2023, 1, 1) # => 2023-01-01 00:00:00 -0600 - t1 = Time.new(2024, 1, 1) # => 2024-01-01 00:00:00 -0600 - -- <tt>%G</tt> - Week-based year: - - t0.strftime('%G') # => "2022" - t1.strftime('%G') # => "2024" - -- <tt>%g</tt> - Week-based year without century, in range (0..99), zero-padded: - - t0.strftime('%g') # => "22" - t1.strftime('%g') # => "24" - -- <tt>%V</tt> - Week number of the week-based year, in range (1..53), - zero-padded: - - t0.strftime('%V') # => "52" - t1.strftime('%V') # => "01" - -==== Literals - -- <tt>%n</tt> - Newline character "\n": - - Time.now.strftime('%n') # => "\n" - -- <tt>%t</tt> - Tab character "\t": - - Time.now.strftime('%t') # => "\t" - -- <tt>%%</tt> - Percent character '%': - - Time.now.strftime('%%') # => "%" - -==== Shorthand Conversion Specifiers - -Each shorthand specifier here is shown with its corresponding -longhand specifier. - -- <tt>%c</tt> - \Date and time: - - Time.now.strftime('%c') # => "Wed Jun 29 08:01:41 2022" - Time.now.strftime('%a %b %e %T %Y') # => "Wed Jun 29 08:02:07 2022" - -- <tt>%D</tt> - \Date: - - Time.now.strftime('%D') # => "06/29/22" - Time.now.strftime('%m/%d/%y') # => "06/29/22" - -- <tt>%F</tt> - ISO 8601 date: - - Time.now.strftime('%F') # => "2022-06-29" - Time.now.strftime('%Y-%m-%d') # => "2022-06-29" - -- <tt>%v</tt> - VMS date: - - Time.now.strftime('%v') # => "29-JUN-2022" - Time.now.strftime('%e-%^b-%4Y') # => "29-JUN-2022" - -- <tt>%x</tt> - Same as <tt>%D</tt>. - -- <tt>%X</tt> - Same as <tt>%T</tt>. - -- <tt>%r</tt> - 12-hour time: - - Time.new(2022, 1, 1, 1).strftime('%r') # => "01:00:00 AM" - Time.new(2022, 1, 1, 1).strftime('%I:%M:%S %p') # => "01:00:00 AM" - Time.new(2022, 1, 1, 13).strftime('%r') # => "01:00:00 PM" - Time.new(2022, 1, 1, 13).strftime('%I:%M:%S %p') # => "01:00:00 PM" - -- <tt>%R</tt> - 24-hour time: - - Time.new(2022, 1, 1, 1).strftime('%R') # => "01:00" - Time.new(2022, 1, 1, 1).strftime('%H:%M') # => "01:00" - Time.new(2022, 1, 1, 13).strftime('%R') # => "13:00" - Time.new(2022, 1, 1, 13).strftime('%H:%M') # => "13:00" - -- <tt>%T</tt> - 24-hour time: - - Time.new(2022, 1, 1, 1).strftime('%T') # => "01:00:00" - Time.new(2022, 1, 1, 1).strftime('%H:%M:%S') # => "01:00:00" - Time.new(2022, 1, 1, 13).strftime('%T') # => "13:00:00" - Time.new(2022, 1, 1, 13).strftime('%H:%M:%S') # => "13:00:00" - -- <tt>%+</tt> (not supported in Time#strftime) - \Date and time: - - DateTime.now.strftime('%+') - # => "Wed Jun 29 08:31:53 -05:00 2022" - DateTime.now.strftime('%a %b %e %H:%M:%S %Z %Y') - # => "Wed Jun 29 08:32:18 -05:00 2022" - -=== Flags - -Flags may affect certain formatting specifications. - -Multiple flags may be given with a single conversion specified; -order does not matter. - -==== Padding Flags - -- <tt>0</tt> - Pad with zeroes: - - Time.new(10).strftime('%0Y') # => "0010" - -- <tt>_</tt> - Pad with blanks: - - Time.new(10).strftime('%_Y') # => " 10" - -- <tt>-</tt> - Don't pad: - - Time.new(10).strftime('%-Y') # => "10" - -==== Casing Flags - -- <tt>^</tt> - Upcase result: - - Time.new(2022, 1).strftime('%B') # => "January" # No casing flag. - Time.new(2022, 1).strftime('%^B') # => "JANUARY" - -- <tt>#</tt> - Swapcase result: - - Time.now.strftime('%p') # => "AM" - Time.now.strftime('%^p') # => "AM" - Time.now.strftime('%#p') # => "am" - -==== Timezone Flags - -- <tt>:</tt> - Put timezone as colon-separated hours and minutes: - - Time.now.strftime('%:z') # => "-05:00" - -- <tt>::</tt> - Put timezone as colon-separated hours, minutes, and seconds: - - Time.now.strftime('%::z') # => "-05:00:00" - -=== Width Specifiers - -The integer width specifier gives a minimum width for the returned string: - - Time.new(2002).strftime('%Y') # => "2002" # No width specifier. - Time.new(2002).strftime('%10Y') # => "0000002002" - Time.new(2002, 12).strftime('%B') # => "December" # No width specifier. - Time.new(2002, 12).strftime('%10B') # => " December" - Time.new(2002, 12).strftime('%3B') # => "December" # Ignored if too small. - -== Specialized Format Strings - -Here are a few specialized format strings, -each based on an external standard. - -=== HTTP Format - -The HTTP date format is based on -{RFC 2616}[https://datatracker.ietf.org/doc/html/rfc2616], -and treats dates in the format <tt>'%a, %d %b %Y %T GMT'</tt>: - - d = Date.new(2001, 2, 3) # => #<Date: 2001-02-03> - # Return HTTP-formatted string. - httpdate = d.httpdate # => "Sat, 03 Feb 2001 00:00:00 GMT" - # Return new date parsed from HTTP-formatted string. - Date.httpdate(httpdate) # => #<Date: 2001-02-03> - # Return hash parsed from HTTP-formatted string. - Date._httpdate(httpdate) - # => {:wday=>6, :mday=>3, :mon=>2, :year=>2001, :hour=>0, :min=>0, :sec=>0, :zone=>"GMT", :offset=>0} - -=== RFC 3339 Format - -The RFC 3339 date format is based on -{RFC 3339}[https://datatracker.ietf.org/doc/html/rfc3339]: - - d = Date.new(2001, 2, 3) # => #<Date: 2001-02-03> - # Return 3339-formatted string. - rfc3339 = d.rfc3339 # => "2001-02-03T00:00:00+00:00" - # Return new date parsed from 3339-formatted string. - Date.rfc3339(rfc3339) # => #<Date: 2001-02-03> - # Return hash parsed from 3339-formatted string. - Date._rfc3339(rfc3339) - # => {:year=>2001, :mon=>2, :mday=>3, :hour=>0, :min=>0, :sec=>0, :zone=>"+00:00", :offset=>0} - -=== RFC 2822 Format - -The RFC 2822 date format is based on -{RFC 2822}[https://datatracker.ietf.org/doc/html/rfc2822], -and treats dates in the format <tt>'%a, %-d %b %Y %T %z'</tt>]: - - d = Date.new(2001, 2, 3) # => #<Date: 2001-02-03> - # Return 2822-formatted string. - rfc2822 = d.rfc2822 # => "Sat, 3 Feb 2001 00:00:00 +0000" - # Return new date parsed from 2822-formatted string. - Date.rfc2822(rfc2822) # => #<Date: 2001-02-03> - # Return hash parsed from 2822-formatted string. - Date._rfc2822(rfc2822) - # => {:wday=>6, :mday=>3, :mon=>2, :year=>2001, :hour=>0, :min=>0, :sec=>0, :zone=>"+0000", :offset=>0} - -=== JIS X 0301 Format - -The JIS X 0301 format includes the -{Japanese era name}[https://en.wikipedia.org/wiki/Japanese_era_name], -and treats dates in the format <tt>'%Y-%m-%d'</tt> -with the first letter of the romanized era name prefixed: - - d = Date.new(2001, 2, 3) # => #<Date: 2001-02-03> - # Return 0301-formatted string. - jisx0301 = d.jisx0301 # => "H13.02.03" - # Return new date parsed from 0301-formatted string. - Date.jisx0301(jisx0301) # => #<Date: 2001-02-03> - # Return hash parsed from 0301-formatted string. - Date._jisx0301(jisx0301) # => {:year=>2001, :mon=>2, :mday=>3} - -=== ISO 8601 Format Specifications - -This section shows format specifications that are compatible with -{ISO 8601}[https://en.wikipedia.org/wiki/ISO_8601]. -Details for various formats may be seen at the links. - -Examples in this section assume: - - t = Time.now # => 2022-06-29 16:49:25.465246 -0500 - -==== Dates - -See {ISO 8601 dates}[https://en.wikipedia.org/wiki/ISO_8601#Dates]. - -- {Years}[https://en.wikipedia.org/wiki/ISO_8601#Years]: - - - Basic year (+YYYY+): - - t.strftime('%Y') # => "2022" - - - Expanded year (<tt>±YYYYY</tt>): - - t.strftime('+%5Y') # => "+02022" - t.strftime('-%5Y') # => "-02022" - -- {Calendar dates}[https://en.wikipedia.org/wiki/ISO_8601#Calendar_dates]: - - - Basic date (+YYYYMMDD+): - - t.strftime('%Y%m%d') # => "20220629" - - - Extended date (<tt>YYYY-MM-DD</tt>): - - t.strftime('%Y-%m-%d') # => "2022-06-29" - - - Reduced extended date (<tt>YYYY-MM</tt>): - - t.strftime('%Y-%m') # => "2022-06" - -- {Week dates}[https://en.wikipedia.org/wiki/ISO_8601#Week_dates]: - - - Basic date (+YYYYWww+ or +YYYYWwwD+): - - t.strftime('%Y%Ww') # => "202226w" - t.strftime('%Y%Ww%u') # => "202226w3" - - - Extended date (<tt>YYYY-Www</tt> or <tt>YYYY-Www-D<tt>): - - t.strftime('%Y-%Ww') # => "2022-26w" - t.strftime('%Y-%Ww-%u') # => "2022-26w-3" - -- {Ordinal dates}[https://en.wikipedia.org/wiki/ISO_8601#Ordinal_dates]: - - - Basic date (+YYYYDDD+): - - t.strftime('%Y%j') # => "2022180" - - - Extended date (<tt>YYYY-DDD</tt>): - - t.strftime('%Y-%j') # => "2022-180" - -==== Times - -See {ISO 8601 times}[https://en.wikipedia.org/wiki/ISO_8601#Times]. - -- Times: - - - Basic time (+Thhmmss.sss+, +Thhmmss+, +Thhmm+, or +Thh+): - - t.strftime('T%H%M%S.%L') # => "T164925.465" - t.strftime('T%H%M%S') # => "T164925" - t.strftime('T%H%M') # => "T1649" - t.strftime('T%H') # => "T16" - - - Extended time (+Thh:mm:ss.sss+, +Thh:mm:ss+, or +Thh:mm+): - - t.strftime('T%H:%M:%S.%L') # => "T16:49:25.465" - t.strftime('T%H:%M:%S') # => "T16:49:25" - t.strftime('T%H:%M') # => "T16:49" - -- {Time zone designators}[https://en.wikipedia.org/wiki/ISO_8601#Time_zone_designators]: - - - Timezone (+time+ represents a valid time, - +hh+ represents a valid 2-digit hour, - and +mm+ represents a valid 2-digit minute): - - - Basic timezone (<tt>time±hhmm</tt>, <tt>time±hh</tt>, or +timeZ+): - - t.strftime('T%H%M%S%z') # => "T164925-0500" - t.strftime('T%H%M%S%z').slice(0..-3) # => "T164925-05" - t.strftime('T%H%M%SZ') # => "T164925Z" - - - Extended timezone (<tt>time±hh:mm</tt>): - - t.strftime('T%H:%M:%S%z') # => "T16:49:25-0500" - - - See also: - - - {Local time (unqualified)}[https://en.wikipedia.org/wiki/ISO_8601#Local_time_(unqualified)]. - - {Coordinated Universal Time (UTC)}[https://en.wikipedia.org/wiki/ISO_8601#Coordinated_Universal_Time_(UTC)]. - - {Time offsets from UTC}[https://en.wikipedia.org/wiki/ISO_8601#Time_offsets_from_UTC]. - -==== Combined \Date and \Time - -See {ISO 8601 Combined date and time representations}[https://en.wikipedia.org/wiki/ISO_8601#Combined_date_and_time_representations]. - -An ISO 8601 combined date and time representation may be any -ISO 8601 date and any ISO 8601 time, -separated by the letter +T+. - -For the relevant +strftime+ formats, see -{Dates}[rdoc-ref:strftime_formatting.rdoc@Dates] -and {Times}[rdoc-ref:strftime_formatting.rdoc@Times] above. |
