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
.
Clone internal hash.
Equivalent to self.to_s.start_with?
; see String#start_with?
.
Iterates over each line in the file and yields a String
object for each.
This method is called when the parser found syntax error.
Parses src
and create S-exp tree. This method is mainly for developer use. The filename
argument is mostly ignored. By default, this method does not handle syntax errors in src
, returning nil
in such cases. Use the raise_errors
keyword to raise a SyntaxError
for an error in src
.
require 'ripper' require 'pp' pp Ripper.sexp_raw("def m(a) nil end") #=> [:program, [:stmts_add, [:stmts_new], [:def, [:@ident, "m", [1, 4]], [:paren, [:params, [[:@ident, "a", [1, 6]]], nil, nil, nil]], [:bodystmt, [:stmts_add, [:stmts_new], [:var_ref, [:@kw, "nil", [1, 9]]]], nil, nil, nil]]]]
Requests a connection to be made on the given remote_sockaddr
after O_NONBLOCK is set for the underlying file descriptor. Returns 0 if successful, otherwise an exception is raised.
# +remote_sockaddr+ - the +struct+ sockaddr contained in a string or Addrinfo object
# Pull down Google's web page require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(80, 'www.google.com') begin # emulate blocking connect socket.connect_nonblock(sockaddr) rescue IO::WaitWritable IO.select(nil, [socket]) # wait 3-way handshake completion begin socket.connect_nonblock(sockaddr) # check connection failure rescue Errno::EISCONN end end socket.write("GET / HTTP/1.0\r\n\r\n") results = socket.read
Refer to Socket#connect
for the exceptions that may be thrown if the call to connect_nonblock fails.
Socket#connect_nonblock
may raise any error corresponding to connect(2) failure, including Errno::EINPROGRESS.
If the exception is Errno::EINPROGRESS, it is extended by IO::WaitWritable
. So IO::WaitWritable
can be used to rescue the exceptions for retrying connect_nonblock.
By specifying a keyword argument exception to false
, you can indicate that connect_nonblock
should not raise an IO::WaitWritable
exception, but return the symbol :wait_writable
instead.
# Socket#connect
Returns an address of the socket suitable for connect in the local machine.
This method returns self.local_address, except following condition.
IPv4 unspecified address (0.0.0.0) is replaced by IPv4 loopback address (127.0.0.1).
IPv6 unspecified address (::) is replaced by IPv6 loopback address (::1).
If the local address is not suitable for connect, SocketError
is raised. IPv4 and IPv6 address which port is 0 is not suitable for connect. Unix domain socket which has no path is not suitable for connect.
Addrinfo.tcp("0.0.0.0", 0).listen {|serv| p serv.connect_address #=> #<Addrinfo: 127.0.0.1:53660 TCP> serv.connect_address.connect {|c| s, _ = serv.accept p [c, s] #=> [#<Socket:fd 4>, #<Socket:fd 6>] } }
creates a new Socket
connected to the address of local_addrinfo
.
If local_addrinfo is nil, the address of the socket is not bound.
The timeout specify the seconds for timeout. Errno::ETIMEDOUT is raised when timeout occur.
If a block is given the created socket is yielded for each address.
creates a socket connected to the address of self.
If one or more arguments given as local_addr_args, it is used as the local address of the socket. local_addr_args is given for family_addrinfo
to obtain actual address.
If local_addr_args is not given, the local address of the socket is not bound.
The optional last argument opts is options represented by a hash. opts may have following options:
specify the timeout in seconds.
If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.
Addrinfo.tcp("www.ruby-lang.org", 80).connect_from("0.0.0.0", 4649) {|s| s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n" puts s.read } # Addrinfo object can be taken for the argument. Addrinfo.tcp("www.ruby-lang.org", 80).connect_from(Addrinfo.tcp("0.0.0.0", 4649)) {|s| s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n" puts s.read }
creates a socket connected to remote_addr_args and bound to self.
The optional last argument opts is options represented by a hash. opts may have following options:
specify the timeout in seconds.
If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.
Addrinfo.tcp("0.0.0.0", 4649).connect_to("www.ruby-lang.org", 80) {|s| s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n" puts s.read }
Calls the block with each remaining line read from the stream; does nothing if already at end-of-file; returns self
. See Line IO.
StringIO#each
is an alias for StringIO#each_line
.
With a block given, calls the block with each remaining character in the stream; see Character IO.
With no block given, returns an enumerator.
Scans the string until the pattern
is matched. Advances the scan pointer if advance_pointer_p
, otherwise not. Returns the matched string if return_string_p
is true, otherwise returns the number of bytes advanced. This method does affect the match register.
Returns a new Hash object; each entry has:
A key provided by the block.
The value from self
.
An optional hash argument can be provided to map keys to new keys. Any key not given will be mapped using the provided block, or remain the same if no block is given.
Transform keys:
h = {foo: 0, bar: 1, baz: 2} h1 = h.transform_keys {|key| key.to_s } h1 # => {"foo"=>0, "bar"=>1, "baz"=>2} h.transform_keys(foo: :bar, bar: :foo) #=> {bar: 0, foo: 1, baz: 2} h.transform_keys(foo: :hello, &:to_s) #=> {:hello=>0, "bar"=>1, "baz"=>2}
Overwrites values for duplicate keys:
h = {foo: 0, bar: 1, baz: 2} h1 = h.transform_keys {|key| :bat } h1 # => {:bat=>2}
Returns a new Enumerator if no block given:
h = {foo: 0, bar: 1, baz: 2} e = h.transform_keys # => #<Enumerator: {:foo=>0, :bar=>1, :baz=>2}:transform_keys> h1 = e.each { |key| key.to_s } h1 # => {"foo"=>0, "bar"=>1, "baz"=>2}
Same as Hash#transform_keys
but modifies the receiver in place instead of returning a new hash.
Returns a new Hash object; each entry has:
A key from self
.
A value provided by the block.
Transform values:
h = {foo: 0, bar: 1, baz: 2} h1 = h.transform_values {|value| value * 100} h1 # => {:foo=>0, :bar=>100, :baz=>200}
Returns a new Enumerator if no block given:
h = {foo: 0, bar: 1, baz: 2} e = h.transform_values # => #<Enumerator: {:foo=>0, :bar=>1, :baz=>2}:transform_values> h1 = e.each { |value| value * 100} h1 # => {:foo=>0, :bar=>100, :baz=>200}
Returns self
, whose keys are unchanged, and whose values are determined by the given block.
h = {foo: 0, bar: 1, baz: 2} h.transform_values! {|value| value * 100} # => {:foo=>0, :bar=>100, :baz=>200}
Returns a new Enumerator if no block given:
h = {foo: 0, bar: 1, baz: 2} e = h.transform_values! # => #<Enumerator: {:foo=>0, :bar=>100, :baz=>200}:transform_values!> h1 = e.each {|value| value * 100} h1 # => {:foo=>0, :bar=>100, :baz=>200}
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
Iterates over each character of each file in ARGF
.
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 character of the first file has been returned, the first character of the second file is returned. The ARGF.filename
method can be used to determine the name of the file in which the current character appears.
If no block is given, an enumerator is returned instead.
Returns the encoded quote character; used for parsing and writing; see {Option quote_char
}:
CSV.new('').quote_char # => "\""
Returns the Regexp used to identify comment lines; used for parsing; see {Option skip_lines
}:
CSV.new('').skip_lines # => nil
Returns the encoding of the internal IO
object.