Returns the Julian start date for calendar reform; if not an infinity, the returned value is suitable for passing to Date#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 # => Infinity
See argument start.
Returns a new Date object representing the following day:
d = Date.new(2001, 2, 3) d.to_s # => "2001-02-03" d.next.to_s # => "2001-02-04"
Parses the given representation of date and time, and creates a DateTime
object.
This method does not function as a validator. If the input string does not match valid formats strictly, you may get a cryptic result. Should consider to use DateTime.strptime
instead of this method as possible.
If the optional second argument is true and the detected year is in the range “00” to “99”, makes it full.
DateTime.parse('2001-02-03T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.parse('20010203T040506+0700') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.parse('3rd Feb 2001 04:05:06 PM') #=> #<DateTime: 2001-02-03T16:05:06+00:00 ...>
Raise an ArgumentError
when the string length is longer than limit. You can stop this check by passing limit: nil
, but note that it may take a long time to parse.
Takes a string representation of a Time
and attempts to parse it using a heuristic.
This method **does not** function as a validator. If the input string does not match valid formats strictly, you may get a cryptic result. Should consider to use ‘Time.strptime` instead of this method as possible.
require 'time' Time.parse("2010-10-31") #=> 2010-10-31 00:00:00 -0500
Any missing pieces of the date are inferred based on the current date.
require 'time' # assuming the current date is "2011-10-31" Time.parse("12:00") #=> 2011-10-31 12:00:00 -0500
We can change the date used to infer our missing elements by passing a second object that responds to mon
, day
and year
, such as Date
, Time
or DateTime
. We can also use our own object.
require 'time' class MyDate attr_reader :mon, :day, :year def initialize(mon, day, year) @mon, @day, @year = mon, day, year end end d = Date.parse("2010-10-28") t = Time.parse("2010-10-29") dt = DateTime.parse("2010-10-30") md = MyDate.new(10,31,2010) Time.parse("12:00", d) #=> 2010-10-28 12:00:00 -0500 Time.parse("12:00", t) #=> 2010-10-29 12:00:00 -0500 Time.parse("12:00", dt) #=> 2010-10-30 12:00:00 -0500 Time.parse("12:00", md) #=> 2010-10-31 12:00:00 -0500
If a block is given, the year described in date
is converted by the block. This is specifically designed for handling two digit years. For example, if you wanted to treat all two digit years prior to 70 as the year 2000+ you could write this:
require 'time' Time.parse("01-10-31") {|year| year + (year < 70 ? 2000 : 1900)} #=> 2001-10-31 00:00:00 -0500 Time.parse("70-10-31") {|year| year + (year < 70 ? 2000 : 1900)} #=> 1970-10-31 00:00:00 -0500
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:
require 'time' # Suppose it is "Thu Nov 29 14:33:20 2001" now and # your time zone is EST which is GMT-5. now = Time.parse("Thu Nov 29 14:33:20 2001") Time.parse("16:30", now) #=> 2001-11-29 16:30:00 -0500 Time.parse("7/23", now) #=> 2001-07-23 00:00:00 -0500 Time.parse("Aug 31", now) #=> 2001-08-31 00:00:00 -0500 Time.parse("Aug 2000", now) #=> 2000-08-01 00:00:00 -0500
Since there are numerous conflicts among locally defined time zone abbreviations all over the world, this method is not intended 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 this fact, this method only understands the time zone abbreviations described in RFC 822 and the system time zone, in the order named. (i.e. a definition in RFC 822 overrides the system time zone definition.) The system time zone is taken from Time.local(year, 1, 1).zone
and Time.local(year, 7, 1).zone
. If the extracted time zone 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 if the Time
class cannot represent specified date.
This method can be used as a 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 of Time.parse
should be checked, though.
You must require ‘time’ to use this method.
Returns the integer day of the month for self
, in range (1..31):
t = Time.new(2000, 1, 2, 3, 4, 5, 6) # => 2000-01-02 03:04:05 +000006 t.mday # => 2
Returns the integer day of the month for self
, in range (1..31):
t = Time.new(2000, 1, 2, 3, 4, 5, 6) # => 2000-01-02 03:04:05 +000006 t.mday # => 2
Returns the integer year for self
:
t = Time.new(2000, 1, 2, 3, 4, 5, 6) # => 2000-01-02 03:04:05 +000006 t.year # => 2000
Returns the integer day of the week for self
, in range (0..6), with Sunday as zero.
t = Time.new(2000, 1, 2, 3, 4, 5, 6) # => 2000-01-02 03:04:05 +000006 t.wday # => 0 t.sunday? # => true
Returns the integer day of the year of self
, in range (1..366).
Time.new(2000, 1, 1).yday # => 1 Time.new(2000, 12, 31).yday # => 366
Returns the string name of the time zone for self
:
Time.utc(2000, 1, 1).zone # => "UTC" Time.new(2000, 1, 1).zone # => "Central Standard Time"
Returns true
if self
represents a Sunday, false
otherwise:
t = Time.utc(2000, 1, 2) # => 2000-01-02 00:00:00 UTC t.sunday? # => true
Related: Time#monday?
, Time#tuesday?
, Time#wednesday?
.
Returns true
if self
represents a Monday, false
otherwise:
t = Time.utc(2000, 1, 3) # => 2000-01-03 00:00:00 UTC t.monday? # => true
Related: Time#tuesday?
, Time#wednesday?
, Time#thursday?
.
Returns true
if self
represents a Tuesday, false
otherwise:
t = Time.utc(2000, 1, 4) # => 2000-01-04 00:00:00 UTC t.tuesday? # => true
Related: Time#wednesday?
, Time#thursday?
, Time#friday?
.
Returns true
if self
represents a Thursday, false
otherwise:
t = Time.utc(2000, 1, 6) # => 2000-01-06 00:00:00 UTC t.thursday? # => true
Related: Time#friday?
, Time#saturday?
, Time#sunday?
.
Returns true
if self
represents a Friday, false
otherwise:
t = Time.utc(2000, 1, 7) # => 2000-01-07 00:00:00 UTC t.friday? # => true
Related: Time#saturday?
, Time#sunday?
, Time#monday?
.
Returns true
if self
represents a Saturday, false
otherwise:
t = Time.utc(2000, 1, 1) # => 2000-01-01 00:00:00 UTC t.saturday? # => true
Related: Time#sunday?
, Time#monday?
, Time#tuesday?
.
Yields self
within raw mode, and returns the result of the block.
STDIN.raw(&:gets)
will read and return a line without echo back and line editing.
The parameter min
specifies the minimum number of bytes that should be received when a read operation is performed. (default: 1)
The parameter time
specifies the timeout in seconds with a precision of 1/10 of a second. (default: 0)
If the parameter intr
is true
, enables break, interrupt, quit, and suspend special characters.
Refer to the manual page of termios for further details.
You must require ‘io/console’ to use this method.
Enables raw mode, and returns io
.
If the terminal mode needs to be back, use io.raw { ... }
.
See IO#raw
for details on the parameters.
You must require ‘io/console’ to use this method.
Returns an array of all lines read from the stream.
When called from class IO (but not subclasses of IO), this method has potential security vulnerabilities if called with untrusted input; see Command Injection.
The first argument must be a string; its meaning depends on whether it starts with the pipe character ('|'
):
If so (and if self
is IO), the rest of the string is a command to be executed as a subprocess.
Otherwise, the string is the path to a file.
With only argument command
given, executes the command in a shell, parses its $stdout into lines, as determined by the default line separator, and returns those lines in an array:
IO.readlines('| cat t.txt') # => ["First line\n", "Second line\n", "\n", "Third line\n", "Fourth line\n"]
With only argument path
given, parses lines from the file at the given path
, as determined by the default line separator, and returns those lines in an array:
IO.readlines('t.txt') # => ["First line\n", "Second line\n", "\n", "Third line\n", "Fourth line\n"]
For both forms, command and path, the remaining arguments are the same.
With argument sep
given, parses lines as determined by that line separator (see Line Separator):
# Ordinary separator. IO.readlines('t.txt', 'li') # =>["First li", "ne\nSecond li", "ne\n\nThird li", "ne\nFourth li", "ne\n"] # Get-paragraphs separator. IO.readlines('t.txt', '') # => ["First line\nSecond line\n\n", "Third line\nFourth line\n"] # Get-all separator. IO.readlines('t.txt', nil) # => ["First line\nSecond line\n\nThird line\nFourth line\n"]
With argument limit
given, parses lines as determined by the default line separator and the given line-length limit (see Line Limit):
IO.readlines('t.txt', 7) # => ["First l", "ine\n", "Second ", "line\n", "\n", "Third l", "ine\n", "Fourth ", "line\n"]
With arguments sep
and limit
given, parses lines as determined by the given line separator and the given line-length limit (see Line Separator and Line Limit):
Optional keyword arguments opts
specify:
Encoding options.
Returns the current line number for the stream; see Line Number.
Sets and returns the line number for the stream; see Line Number.
Reads and returns all remaining line from the stream; does not modify $_
. See Line IO.
With no arguments given, returns lines as determined by line separator $/
, or nil
if none:
f = File.new('t.txt') f.readlines # => ["First line\n", "Second line\n", "\n", "Fourth line\n", "Fifth line\n"] f.readlines # => [] f.close
With only string argument sep
given, returns lines as determined by line separator sep
, or nil
if none; see Line Separator:
f = File.new('t.txt') f.readlines('li') # => ["First li", "ne\nSecond li", "ne\n\nFourth li", "ne\nFifth li", "ne\n"] f.close
The two special values for sep
are honored:
f = File.new('t.txt') # Get all into one string. f.readlines(nil) # => ["First line\nSecond line\n\nFourth line\nFifth line\n"] # Get paragraphs (up to two line separators). f.rewind f.readlines('') # => ["First line\nSecond line\n\n", "Fourth line\nFifth line\n"] f.close
With only integer argument limit
given, limits the number of bytes in each line; see Line Limit:
f = File.new('t.txt') f.readlines(8) # => ["First li", "ne\n", "Second l", "ine\n", "\n", "Fourth l", "ine\n", "Fifth li", "ne\n"] f.close
With arguments sep
and limit
given, combines the two behaviors:
Returns lines as determined by line separator sep
.
But returns no more bytes in a line than are allowed by the limit.
Optional keyword argument chomp
specifies whether line separators are to be omitted:
f = File.new('t.txt') f.readlines(chomp: true) # => ["First line", "Second line", "", "Fourth line", "Fifth line"] f.close
Reads up to maxlen
bytes from the stream; returns a string (either a new string or the given out_string
). Its encoding is:
The unchanged encoding of out_string
, if out_string
is given.
ASCII-8BIT, otherwise.
Contains maxlen
bytes from the stream, if available.
Otherwise contains all available bytes, if any available.
Otherwise is an empty string.
With the single non-negative integer argument maxlen
given, returns a new string:
f = File.new('t.txt') f.readpartial(20) # => "First line\nSecond l" f.readpartial(20) # => "ine\n\nFourth line\n" f.readpartial(20) # => "Fifth line\n" f.readpartial(20) # Raises EOFError. f.close
With both argument maxlen
and string argument out_string
given, returns modified out_string
:
f = File.new('t.txt') s = 'foo' f.readpartial(20, s) # => "First line\nSecond l" s = 'bar' f.readpartial(0, s) # => "" f.close
This method is useful for a stream such as a pipe, a socket, or a tty. It blocks only when no data is immediately available. This means that it blocks only when all of the following are true:
The byte buffer in the stream is empty.
The content of the stream is empty.
The stream is not at EOF.
When blocked, the method waits for either more data or EOF on the stream:
If more data is read, the method returns the data.
If EOF is reached, the method raises EOFError
.
When not blocked, the method responds immediately:
Returns data from the buffer if there is any.
Otherwise returns data from the stream if there is any.
Otherwise raises EOFError
if the stream has reached EOF.
Note that this method is similar to sysread. The differences are:
If the byte buffer is not empty, read from the byte buffer instead of “sysread for buffered IO
(IOError
)”.
It doesn’t cause Errno::EWOULDBLOCK and Errno::EINTR. When readpartial meets EWOULDBLOCK and EINTR by read system call, readpartial retries the system call.
The latter means that readpartial is non-blocking-flag insensitive. It blocks on the situation IO#sysread
causes Errno::EWOULDBLOCK as if the fd is blocking mode.
Examples:
# # Returned Buffer Content Pipe Content r, w = IO.pipe # w << 'abc' # "" "abc". r.readpartial(4096) # => "abc" "" "" r.readpartial(4096) # (Blocks because buffer and pipe are empty.) # # Returned Buffer Content Pipe Content r, w = IO.pipe # w << 'abc' # "" "abc" w.close # "" "abc" EOF r.readpartial(4096) # => "abc" "" EOF r.readpartial(4096) # raises EOFError # # Returned Buffer Content Pipe Content r, w = IO.pipe # w << "abc\ndef\n" # "" "abc\ndef\n" r.gets # => "abc\n" "def\n" "" w << "ghi\n" # "def\n" "ghi\n" r.readpartial(4096) # => "def\n" "" "ghi\n" r.readpartial(4096) # => "ghi\n" "" ""
Reads a line as with IO#gets
, but raises EOFError
if already at end-of-stream.
Optional keyword argument chomp
specifies whether line separators are to be omitted.