Erases the line at the cursor corresponding to mode. mode may be either: 0: after cursor 1: before and cursor 2: entire line
You must require ‘io/console’ to use this method.
Calls the block with each remaining line read from the stream; returns self. Does nothing if already at end-of-stream; See Line IO.
With no arguments given, reads lines as determined by line separator $/:
f = File.new('t.txt') f.each_line {|line| p line } f.each_line {|line| fail 'Cannot happen' } f.close
Output:
"First line\n" "Second line\n" "\n" "Fourth line\n" "Fifth line\n"
With only string argument sep given, reads lines as determined by line separator sep; see Line Separator:
f = File.new('t.txt') f.each_line('li') {|line| p line } f.close
Output:
"First li" "ne\nSecond li" "ne\n\nFourth li" "ne\nFifth li" "ne\n"
The two special values for sep are honored:
f = File.new('t.txt') # Get all into one string. f.each_line(nil) {|line| p line } f.close
Output:
"First line\nSecond line\n\nFourth line\nFifth line\n" f.rewind # Get paragraphs (up to two line separators). f.each_line('') {|line| p line }
Output:
"First line\nSecond line\n\n" "Fourth line\nFifth line\n"
With only integer argument limit given, limits the number of bytes in each line; see Line Limit:
f = File.new('t.txt') f.each_line(8) {|line| p line } f.close
Output:
"First li" "ne\n" "Second l" "ine\n" "\n" "Fourth l" "ine\n" "Fifth li" "ne\n"
With arguments sep and limit given, combines the two behaviors (see Line Separator and Line Limit).
Optional keyword argument chomp specifies whether line separators are to be omitted:
f = File.new('t.txt') f.each_line(chomp: true) {|line| p line } f.close
Output:
"First line" "Second line" "" "Fourth line" "Fifth line"
Returns an Enumerator if no block is given.
Calls the given block with each codepoint in the stream; returns self:
f = File.new('t.rus') a = [] f.each_codepoint {|c| a << c } a # => [1090, 1077, 1089, 1090] f.close
Returns an Enumerator if no block is given.
Related: IO#each_byte, IO#each_char.
Returns the Encoding object that represents the encoding of the stream, or nil if the stream is in write mode and no encoding is specified.
See Encodings.
See Encodings.
Argument ext_enc, if given, must be an Encoding object or a String with the encoding name; it is assigned as the encoding for the stream.
Argument int_enc, if given, must be an Encoding object or a String with the encoding name; it is assigned as the encoding for the internal string.
Argument 'ext_enc:int_enc', if given, is a string containing two colon-separated encoding names; corresponding Encoding objects are assigned as the external and internal encodings for the stream.
If the external encoding of a string is binary/ASCII-8BIT, the internal encoding of the string is set to nil, since no transcoding is needed.
Optional keyword arguments enc_opts specify Encoding options.
With no argument, returns the value of $!, which is the result of the most recent pattern match (see Regexp global variables):
/c(.)t/ =~ 'cat' # => 0 Regexp.last_match # => #<MatchData "cat" 1:"a"> /a/ =~ 'foo' # => nil Regexp.last_match # => nil
With non-negative integer argument n, returns the _n_th field in the matchdata, if any, or nil if none:
/c(.)t/ =~ 'cat' # => 0 Regexp.last_match(0) # => "cat" Regexp.last_match(1) # => "a" Regexp.last_match(2) # => nil
With negative integer argument n, counts backwards from the last field:
Regexp.last_match(-1) # => "a"
With string or symbol argument name, returns the string value for the named capture, if any:
/(?<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" Regexp.last_match('foo') # Raises IndexError.
Returns true if matching against re can be done in linear time to the input string.
Regexp.linear_time?(/re/) # => true
Note that this is a property of the ruby interpreter, not of the argument regular expression. Identical regexp can or cannot run in linear time depending on your ruby binary. Neither forward nor backward compatibility is guaranteed about the return value of this method. Our current algorithm is (*1) but this is subject to change in the future. Alternative implementations can also behave differently. They might always return false for everything.
Returns false if self is applicable to a string with any ASCII-compatible encoding; otherwise returns true:
r = /a/ # => /a/ r.fixed_encoding? # => false r.match?("\u{6666} a") # => true r.match?("\xa1\xa2 a".force_encoding("euc-jp")) # => true r.match?("abc".force_encoding("euc-jp")) # => true r = /a/u # => /a/ r.fixed_encoding? # => true r.match?("\u{6666} a") # => true r.match?("\xa1\xa2".force_encoding("euc-jp")) # Raises exception. r.match?("abc".force_encoding("euc-jp")) # => true r = /\u{6666}/ # => /\u{6666}/ r.fixed_encoding? # => true r.encoding # => #<Encoding:UTF-8> r.match?("\u{6666} a") # => true r.match?("\xa1\xa2".force_encoding("euc-jp")) # Raises exception. r.match?("abc".force_encoding("euc-jp")) # => false
Dup internal hash.
Clone internal hash.
Returns true if the class was initialized with keyword_init: true. Otherwise returns nil or false.
Examples:
Foo = Struct.new(:a) Foo.keyword_init? # => nil Bar = Struct.new(:a, keyword_init: true) Bar.keyword_init? # => true Baz = Struct.new(:a, keyword_init: false) Baz.keyword_init? # => false
Iterates over each line in the file and yields a String object for each.
Packs port and host as an AF_INET/AF_INET6 sockaddr string.
Socket.sockaddr_in(80, "127.0.0.1") #=> "\x02\x00\x00P\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00" Socket.sockaddr_in(80, "::1") #=> "\n\x00\x00P\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00"
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.
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 IPv6 link local address (fe80::/10). It returns false otherwise.
Returns true for IPv4-mapped IPv6 address (::ffff:0:0/80). It returns false otherwise.
Calls the block with each remaining line read from the stream; does nothing if already at end-of-file; returns self. See Line IO.
With a block given, calls the block with each remaining codepoint in the stream; see Codepoint IO.
With no block given, returns an enumerator.
Returns the Encoding object that represents the encoding of the file. If the stream is write mode and no encoding is specified, 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 size of the most recent match in bytes, or nil if there was no recent match. This is different than matched.size, which will return the size in characters.
s = StringScanner.new('test string') s.check /\w+/ # -> "test" s.matched_size # -> 4 s.check /\d+/ # -> nil s.matched_size # -> nil
Returns the pre-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 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"