Return the number of seconds the specified time zone differs from UTC.
Numeric time zones that include minutes, such as -10:00 or +1330 will work, as will simpler hour-only time zones like -10 or +13.
Textual time zones listed in ZoneOffset are also supported.
If the time zone does not match any of the above, zone_offset will check if the local time zone (both with and without potential Daylight Saving Time changes being in effect) matches zone. Specifying a value for year will change the year used to find the local time zone.
If zone_offset is unable to determine the offset, nil will be returned.
require 'time' Time.zone_offset("EST") #=> -18000
You must require ‘time’ to use this method.
Returns a hash of the name/value pairs, to use in pattern matching. Possible keys are: :year, :month, :day, :yday, :wday, :hour, :min, :sec, :subsec, :dst, :zone.
Possible usages:
t = Time.utc(2022, 10, 5, 21, 25, 30) if t in wday: 3, day: ..7 # uses deconstruct_keys underneath puts "first Wednesday of the month" end #=> prints "first Wednesday of the month" case t 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 t in Time(wday: 3, day: ..7) puts "first Wednesday of the month" end
Returns a data represents the current console mode.
You must require ‘io/console’ to use this method.
Waits until IO is readable and returns a truthy value, or a falsy value when times out. Returns a truthy value immediately when buffered data is available.
You must require ‘io/wait’ to use this method.
Calls the given block with each character in the stream; returns self. See Character IO.
f = File.new('t.rus') a = [] f.each_char {|c| a << c.ord } a # => [1090, 1077, 1089, 1090] f.close
Returns an Enumerator if no block is given.
Related: IO#each_byte, IO#each_codepoint.
Returns self.
Closes the stream for writing if open for writing; returns nil. See Open and Closed Streams.
Flushes any buffered writes to the operating system before closing.
If the stream was opened by IO.popen and is also closed for reading, sets global variable $? (child exit status).
IO.popen('ruby', 'r+') do |pipe| puts pipe.closed? pipe.close_read puts pipe.closed? pipe.close_write puts $? puts pipe.closed? end
Output:
false false pid 15044 exit 0 true
Related: IO#close, IO#close_read, IO#closed?.
Returns the path associated with the IO, or nil if there is no path associated with the IO. It is not guaranteed that the path exists on the filesystem.
$stdin.path # => "<STDIN>" File.open("testfile") {|f| f.path} # => "testfile"
Reads at most maxlen bytes from ios using the read(2) system call after O_NONBLOCK is set for the underlying file descriptor.
If the optional outbuf argument is present, it must reference a String, which will receive the data. The outbuf will contain only the received data after the method call even if it is not empty at the beginning.
read_nonblock just calls the read(2) system call. It causes all errors the read(2) system call causes: Errno::EWOULDBLOCK, Errno::EINTR, etc. The caller should care such errors.
If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying read_nonblock.
read_nonblock causes EOFError on EOF.
On some platforms, such as Windows, non-blocking mode is not supported on IO objects other than sockets. In such cases, Errno::EBADF will be raised.
If the read byte buffer is not empty, read_nonblock reads from the buffer like readpartial. In this case, the read(2) system call is not called.
When read_nonblock raises an exception kind of IO::WaitReadable, read_nonblock should not be called until io is readable for avoiding busy loop. This can be done as follows.
# emulates blocking read (readpartial). begin result = io.read_nonblock(maxlen) rescue IO::WaitReadable IO.select([io]) retry end
Although IO#read_nonblock doesn’t raise IO::WaitWritable. OpenSSL::Buffering#read_nonblock can raise IO::WaitWritable. If IO and SSL should be used polymorphically, IO::WaitWritable should be rescued too. See the document of OpenSSL::Buffering#read_nonblock for sample code.
Note that this method is identical to readpartial except the non-blocking flag is set.
By specifying a keyword argument exception to false, you can indicate that read_nonblock should not raise an IO::WaitReadable exception, but return the symbol :wait_readable instead. At EOF, it will return nil instead of raising EOFError.
Returns a hash, that will be turned into a JSON object and represent this object.
Stores class name (OpenStruct) with this struct’s values t as a JSON string.
Yields all attributes (as symbols) along with the corresponding values or returns an enumerator if no block is given.
require "ostruct" data = OpenStruct.new("country" => "Australia", :capital => "Canberra") data.each_pair.to_a # => [[:country, "Australia"], [:capital, "Canberra"]]
Returns a hash, that will be turned into a JSON object and represent this object.
Stores class name (Range) with JSON array of arguments a which include first (integer), last (integer), and exclude_end? (boolean) as JSON string.
Deserializes JSON string by constructing new Regexp object with source s (Regexp or String) and options o serialized by to_json
Returns a hash, that will be turned into a JSON object and represent this object.