Returns the Symbol
corresponding to str, creating the symbol if it did not previously exist. See Symbol#id2name
.
"Koala".intern #=> :Koala s = 'cat'.to_sym #=> :cat s == :cat #=> true s = '@cat'.to_sym #=> :@cat s == :@cat #=> true
This can also be used to create symbols that cannot be represented using the :xxx
notation.
'cat and dog'.to_sym #=> :"cat and dog"
Splits str using the supplied parameter as the record separator ($/
by default), passing each substring in turn to the supplied block. If a zero-length record separator is supplied, the string is split into paragraphs delimited by multiple successive newlines.
If chomp
is true
, separator
will be removed from the end of each line.
If no block is given, an enumerator is returned instead.
"hello\nworld".each_line {|s| p s} # prints: # "hello\n" # "world" "hello\nworld".each_line('l') {|s| p s} # prints: # "hel" # "l" # "o\nworl" # "d" "hello\n\n\nworld".each_line('') {|s| p s} # prints # "hello\n\n" # "world" "hello\nworld".each_line(chomp: true) {|s| p s} # prints: # "hello" # "world" "hello\nworld".each_line('l', chomp: true) {|s| p s} # prints: # "he" # "" # "o\nwor" # "d"
Passes each byte in str to the given block, or returns an enumerator if no block is given.
"hello".each_byte {|c| print c, ' ' }
produces:
104 101 108 108 111
Passes the Integer
ordinal of each character in str, also known as a codepoint when applied to Unicode strings to the given block. For encodings other than UTF-8/UTF-16(BE|LE)/UTF-32(BE|LE), values are directly derived from the binary representation of each character.
If no block is given, an enumerator is returned instead.
"hello\u0639".each_codepoint {|c| print c, ' ' }
produces:
104 101 108 108 111 1593
Sets the Fiber
scheduler for the current thread. If the scheduler is set, non-blocking fibers (created by Fiber.new
with blocking: false
, or by Fiber.schedule
) call that scheduler’s hook methods on potentially blocking operations, and the current thread will call scheduler’s close
method on finalization (allowing the scheduler to properly manage all non-finished fibers).
scheduler
can be an object of any class corresponding to Fiber::SchedulerInterface
. Its implementation is up to the user.
See also the “Non-blocking fibers” section in class docs.
Returns the Fiber
scheduler, that was last set for the current thread with Fiber.set_scheduler
if and only if the current fiber is non-blocking.
Returns the locale charmap name. It returns nil if no appropriate information.
Debian GNU/Linux LANG=C Encoding.locale_charmap #=> "ANSI_X3.4-1968" LANG=ja_JP.EUC-JP Encoding.locale_charmap #=> "EUC-JP" SunOS 5 LANG=C Encoding.locale_charmap #=> "646" LANG=ja Encoding.locale_charmap #=> "eucJP"
The result is highly platform dependent. So Encoding.find(Encoding.locale_charmap)
may cause an error. If you need some encoding object even for unknown locale, Encoding.find
(“locale”) can be used.
Return the accept character set for all new CGI
instances.
Calls the given block with each member name/value pair; returns self
:
Customer = Struct.new(:name, :address, :zip) # => Customer joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.each_pair {|(name, value)| p "#{name} => #{value}" }
Output:
"name => Joe Smith" "address => 123 Maple, Anytown NC" "zip => 12345"
Returns an Enumerator
if no block is given.
Related: each
.
Executes the block for every line in ios, where lines are separated by sep. ios must be opened for reading or an IOError
will be raised.
If no block is given, an enumerator is returned instead.
f = File.new("testfile") f.each {|line| puts "#{f.lineno}: #{line}" }
produces:
1: This is line one 2: This is line two 3: This is line three 4: And so on...
See IO.readlines
for details about getline_args.
Calls the given block once for each byte (0..255) in ios, passing the byte as an argument. The stream must be opened for reading or an IOError
will be raised.
If no block is given, an enumerator is returned instead.
f = File.new("testfile") checksum = 0 f.each_byte {|x| checksum ^= x } #=> #<File:testfile> checksum #=> 12
Passes the Integer
ordinal of each character in ios, passing the codepoint as an argument. The stream must be opened for reading or an IOError
will be raised.
If no block is given, an enumerator is returned instead.
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"]]
The first form returns the MatchData
object generated by the last successful pattern match. Equivalent to reading the special global variable $~
(see Special global variables in Regexp
for details).
The second form returns the nth field in this MatchData
object. n can be a string or symbol to reference a named capture.
Note that the last_match
is local to the thread and method scope of the method that did the pattern match.
/c(.)t/ =~ 'cat' #=> 0 Regexp.last_match #=> #<MatchData "cat" 1:"a"> Regexp.last_match(0) #=> "cat" Regexp.last_match(1) #=> "a" Regexp.last_match(2) #=> nil /(?<lhs>\w+)\s*=\s*(?<rhs>\w+)/ =~ "var = val" Regexp.last_match #=> #<MatchData "var = val" lhs:"var" rhs:"val"> Regexp.last_match(:lhs) #=> "var" Regexp.last_match(:rhs) #=> "val"
Returns an array of all the symbols currently in Ruby’s symbol table.
Symbol.all_symbols.size #=> 903 Symbol.all_symbols[1,20] #=> [:floor, :ARGV, :Binding, :symlink, :chown, :EOFError, :$;, :String, :LOCK_SH, :"setuid?", :$<, :default_proc, :compact, :extend, :Tms, :getwd, :$=, :ThreadGroup, :wait2, :$>]
In general, to_sym
returns the Symbol
corresponding to an object. As sym is already a symbol, self
is returned in this case.
Iterates over each component of the path.
Pathname.new("/usr/bin/ruby").each_filename {|filename| ... } # yields "usr", "bin", and "ruby".
Returns an Enumerator
if no block was given.
enum = Pathname.new("/usr/bin/ruby").each_filename # ... do stuff ... enum.each { |e| ... } # yields "usr", "bin", and "ruby".
Iterates over each line in the file and yields a String
object for each.
Iterates over the entries (files and subdirectories) in the directory, yielding a Pathname
object for each entry.