The first form returns the MatchData object generated by the last successful pattern match. Equivalent to reading the special global variable $~ (see Special global variables in Regexp for details).
The second form returns the nth field in this MatchData object. n can be a string or symbol to reference a named capture.
Note that the last_match is local to the thread and method scope of the method that did the pattern match.
/c(.)t/ =~ 'cat' #=> 0 Regexp.last_match #=> #<MatchData "cat" 1:"a"> Regexp.last_match(0) #=> "cat" Regexp.last_match(1) #=> "a" Regexp.last_match(2) #=> nil /(?<lhs>\w+)\s*=\s*(?<rhs>\w+)/ =~ "var = val" Regexp.last_match #=> #<MatchData "var = val" lhs:"var" rhs:"val"> Regexp.last_match(:lhs) #=> "var" Regexp.last_match(:rhs) #=> "val"
Returns false if rxp is applicable to a string with any ASCII compatible encoding. Returns true otherwise.
r = /a/ r.fixed_encoding? #=> false r =~ "\u{6666} a" #=> 2 r =~ "\xa1\xa2 a".force_encoding("euc-jp") #=> 2 r =~ "abc".force_encoding("euc-jp") #=> 0 r = /a/u r.fixed_encoding? #=> true r.encoding #=> #<Encoding:UTF-8> r =~ "\u{6666} a" #=> 2 r =~ "\xa1\xa2".force_encoding("euc-jp") #=> Encoding::CompatibilityError r =~ "abc".force_encoding("euc-jp") #=> 0 r = /\u{6666}/ r.fixed_encoding? #=> true r.encoding #=> #<Encoding:UTF-8> r =~ "\u{6666} a" #=> 0 r =~ "\xa1\xa2".force_encoding("euc-jp") #=> Encoding::CompatibilityError r =~ "abc".force_encoding("euc-jp") #=> nil
Returns a hash, that will be turned into a JSON object and represent this object.
This method is called when the parser found syntax error.
USE OF RIPPER LIBRARY ONLY.
Strips up to width leading whitespaces from input, and returns the stripped column width.
USE OF RIPPER LIBRARY ONLY.
Strips up to width leading whitespaces from input, and returns the stripped column width.
Accepts an incoming connection using accept(2) after O_NONBLOCK is set for the underlying file descriptor. It returns an array containing the accepted socket for the incoming connection, client_socket, and an Addrinfo, client_addrinfo.
# In one script, start this first require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(2200, 'localhost') socket.bind(sockaddr) socket.listen(5) begin # emulate blocking accept client_socket, client_addrinfo = socket.accept_nonblock rescue IO::WaitReadable, Errno::EINTR IO.select([socket]) retry end puts "The client said, '#{client_socket.readline.chomp}'" client_socket.puts "Hello from script one!" socket.close # In another script, start this second require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(2200, 'localhost') socket.connect(sockaddr) socket.puts "Hello from script 2." puts "The server said, '#{socket.readline.chomp}'" socket.close
Refer to Socket#accept for the exceptions that may be thrown if the call to accept_nonblock fails.
Socket#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.
sendmsg_nonblock sends a message using sendmsg(2) system call in non-blocking manner.
It is similar to BasicSocket#sendmsg but the non-blocking flag is set before the system call and it doesn’t retry the system call.
By specifying a keyword argument exception to false, you can indicate that sendmsg_nonblock should not raise an IO::WaitWritable exception, but return the symbol :wait_writable instead.
returns a string which shows the sockaddr in addrinfo with human-readable form.
Addrinfo.tcp("localhost", 80).inspect_sockaddr #=> "127.0.0.1:80" Addrinfo.tcp("ip6-localhost", 80).inspect_sockaddr #=> "[::1]:80" Addrinfo.unix("/tmp/sock").inspect_sockaddr #=> "/tmp/sock"
Returns true for IPv4 multicast address (224.0.0.0/4). It returns false otherwise.
Returns true for IPv6 unspecified address (::). It returns false otherwise.
Returns true for IPv6 multicast address (ff00::/8). It returns false otherwise.
Returns true for IPv4-compatible IPv6 address (::/80). 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.
Returns the Encoding object that represents the encoding of the file. If strio is write mode and no encoding is specified, returns nil.
Returns the Encoding of the internal string if conversion is specified. Otherwise returns nil.
Specify the encoding of the StringIO as ext_enc. Use the default external encoding if ext_enc is nil. 2nd argument int_enc and optional hash opt argument are ignored; they are for API compatibility to IO.
Duplicates a StringScanner object.
Returns the post-match
(in the regular expression sense) of the last scan.s = StringScanner.new('test string') s.scan(/\w+/) # -> "test" s.scan(/\s+/) # -> " " s.pre_match # -> "test" s.post_match # -> "string"
Returns a new hash with the results of running the block once for every key. This method does not change the values.
h = { a: 1, b: 2, c: 3 } h.transform_keys {|k| k.to_s } #=> { "a" => 1, "b" => 2, "c" => 3 } h.transform_keys(&:to_s) #=> { "a" => 1, "b" => 2, "c" => 3 } h.transform_keys.with_index {|k, i| "#{k}.#{i}" } #=> { "a.0" => 1, "b.1" => 2, "c.2" => 3 }
If no block is given, an enumerator is returned instead.
Invokes the given block once for each key in hsh, replacing it with the new key returned by the block, and then returns hsh. This method does not change the values.
h = { a: 1, b: 2, c: 3 } h.transform_keys! {|k| k.to_s } #=> { "a" => 1, "b" => 2, "c" => 3 } h.transform_keys!(&:to_sym) #=> { a: 1, b: 2, c: 3 } h.transform_keys!.with_index {|k, i| "#{k}.#{i}" } #=> { "a.0" => 1, "b.1" => 2, "c.2" => 3 }
If no block is given, an enumerator is returned instead.
Returns a new hash with the results of running the block once for every value. This method does not change the keys.
h = { a: 1, b: 2, c: 3 } h.transform_values {|v| v * v + 1 } #=> { a: 2, b: 5, c: 10 } h.transform_values(&:to_s) #=> { a: "1", b: "2", c: "3" } h.transform_values.with_index {|v, i| "#{v}.#{i}" } #=> { a: "1.0", b: "2.1", c: "3.2" }
If no block is given, an enumerator is returned instead.