Returns true for IPv6 multicast address (ff00::/8). It returns false otherwise.
Returns true for IPv6 link local address (fe80::/10). It returns false otherwise.
Accepts an incoming connection using accept(2) after O_NONBLOCK is set for the underlying file descriptor. It returns an accepted TCPSocket
for the incoming connection.
require 'socket' serv = TCPServer.new(2202) begin # emulate blocking accept sock = serv.accept_nonblock rescue IO::WaitReadable, Errno::EINTR IO.select([serv]) retry end # sock is an accepted socket.
Refer to Socket#accept
for the exceptions that may be thrown if the call to TCPServer#accept_nonblock
fails.
TCPServer#accept_nonblock
may raise any error corresponding to accept(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED, Errno::EPROTO, it is extended by IO::WaitReadable
. So IO::WaitReadable
can be used to rescue the exceptions for retrying accept_nonblock.
By specifying a keyword argument exception to false
, you can indicate that accept_nonblock
should not raise an IO::WaitReadable
exception, but return the symbol :wait_readable
instead.
Accepts an incoming connection using accept(2) after O_NONBLOCK is set for the underlying file descriptor. It returns an accepted UNIXSocket
for the incoming connection.
require 'socket' serv = UNIXServer.new("/tmp/sock") begin # emulate blocking accept sock = serv.accept_nonblock rescue IO::WaitReadable, Errno::EINTR IO.select([serv]) retry end # sock is an accepted socket.
Refer to Socket#accept
for the exceptions that may be thrown if the call to UNIXServer#accept_nonblock
fails.
UNIXServer#accept_nonblock
may raise any error corresponding to accept(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED or Errno::EPROTO, it is extended by IO::WaitReadable
. So IO::WaitReadable
can be used to rescue the exceptions for retrying accept_nonblock.
By specifying a keyword argument exception to false
, you can indicate that accept_nonblock
should not raise an IO::WaitReadable
exception, but return the symbol :wait_readable
instead.
Calls the block with each remaining line read from the stream; does nothing if already at end-of-file; returns self
. See Line IO.
Returns a shallow copy of self
; the [stored string] in the copy is the same string as in self
.
Returns the WIN32OLE::TypeLib
object. The object represents the type library which contains the WIN32OLE
object.
excel = WIN32OLE.new('Excel.Application') tlib = excel.ole_typelib puts tlib.name # -> 'Microsoft Excel 9.0 Object Library'
Evaluates a string containing Ruby source code, or the given block, within the context of the receiver (obj). In order to set the context, the variable self
is set to obj while the code is executing, giving the code access to obj’s instance variables and private methods.
When instance_eval
is given a block, obj is also passed in as the block’s only argument.
When instance_eval
is given a String
, the optional second and third parameters supply a filename and starting line number that are used when reporting compilation errors.
class KlassWithSecret def initialize @secret = 99 end private def the_secret "Ssssh! The secret is #{@secret}." end end k = KlassWithSecret.new k.instance_eval { @secret } #=> 99 k.instance_eval { the_secret } #=> "Ssssh! The secret is 99." k.instance_eval {|obj| obj == self } #=> true
Executes the given block within the context of the receiver (obj). In order to set the context, the variable self
is set to obj while the code is executing, giving the code access to obj’s instance variables. Arguments are passed as block parameters.
class KlassWithSecret def initialize @secret = 99 end end k = KlassWithSecret.new k.instance_exec(5) {|x| @secret+x } #=> 104
Replaces the entire contents of self
with the contents of other_hash
; returns self
:
h = {foo: 0, bar: 1, baz: 2} h.replace({bat: 3, bam: 4}) # => {:bat=>3, :bam=>4}
Returns an enumerator which iterates over each line (separated by sep, which defaults to your platform’s newline character) of each file in ARGV
. If a block is supplied, each line in turn will be yielded to the block, otherwise an enumerator is returned. The optional limit argument is an Integer
specifying the maximum length of each line; longer lines will be split according to this limit.
This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last line of the first file has been returned, the first line of the second file is returned. The ARGF.filename
and ARGF.lineno
methods can be used to determine the filename of the current line and line number of the whole input, respectively.
For example, the following code prints out each line of each named file prefixed with its line number, displaying the filename once per file:
ARGF.each_line do |line| puts ARGF.filename if ARGF.file.lineno == 1 puts "#{ARGF.file.lineno}: #{line}" end
While the following code prints only the first file’s name at first, and the contents with line number counted through all named files.
ARGF.each_line do |line| puts ARGF.filename if ARGF.lineno == 1 puts "#{ARGF.lineno}: #{line}" end
Returns the file extension appended to the names of backup copies of modified files under in-place edit mode. This value can be set using ARGF.inplace_mode=
or passing the -i
switch to the Ruby binary.
Sets the filename extension for in-place editing mode to the given String
. The backup copy of each file being edited has this value appended to its filename.
For example:
$ ruby argf.rb file.txt ARGF.inplace_mode = '.bak' ARGF.each_line do |line| print line.sub("foo","bar") end
First, file.txt.bak is created as a backup copy of file.txt. Then, each line of file.txt has the first occurrence of “foo” replaced with “bar”.
Returns true if the ipaddr is a link-local address. IPv4 addresses in 169.254.0.0/16 reserved by RFC 3927 and link-local IPv6 Unicast Addresses in fe80::/10 reserved by RFC 4291 are considered link-local. Link-local IPv4 addresses in the IPv4-mapped IPv6 address range are also considered link-local.
Returns the Ruby source filename and line number of the binding object.
Outputs obj
to out
like PP.pp
but with no indent and newline.
PP.singleline_pp
returns out
.
This is similar to PrettyPrint::format
but the result has no breaks.
maxwidth
, newline
and genspace
are ignored.
The invocation of breakable
in the block doesn’t break a line and is treated as just an invocation of text
.
Returns true if the referenced object is still alive.
Returns the Ruby source filename and line number containing this proc or nil
if this proc was not defined in Ruby (i.e. native).
Returns the Ruby source filename and line number containing this method or nil if this method was not defined in Ruby (i.e. native).
Returns the Ruby source filename and line number containing this method or nil if this method was not defined in Ruby (i.e. native).
Receive only a specific message.
Instead of Ractor.receive
, Ractor.receive_if
can be given a pattern (or any filter) in a block and you can choose the messages to accept that are available in your ractor’s incoming queue.
r = Ractor.new do p Ractor.receive_if{|msg| msg.match?(/foo/)} #=> "foo3" p Ractor.receive_if{|msg| msg.match?(/bar/)} #=> "bar1" p Ractor.receive_if{|msg| msg.match?(/baz/)} #=> "baz2" end r << "bar1" r << "baz2" r << "foo3" r.take
This will output:
foo3 bar1 baz2
If the block returns a truthy value, the message is removed from the incoming queue and returned. Otherwise, the message remains in the incoming queue and the next messages are checked by the given block.
If there are no messages left in the incoming queue, the method will block until new messages arrive.
If the block is escaped by break/return/exception/throw, the message is removed from the incoming queue as if a truthy value had been returned.
r = Ractor.new do val = Ractor.receive_if{|msg| msg.is_a?(Array)} puts "Received successfully: #{val}" end r.send(1) r.send('test') wait puts "2 non-matching sent, nothing received" r.send([1, 2, 3]) wait
Prints:
2 non-matching sent, nothing received Received successfully: [1, 2, 3]
Note that you can not call receive/receive_if in the given block recursively. You should not do any tasks in the block other than message filtration.
Ractor.current << true Ractor.receive_if{|msg| Ractor.receive} #=> `receive': can not call receive/receive_if recursively (Ractor::Error)
same as Ractor.receive_if
Returns the execution stack for the target thread—an array containing backtrace location objects.
See Thread::Backtrace::Location
for more information.
This method behaves similarly to Kernel#caller_locations
except it applies to a specific thread.