Iterates the given block over all prime numbers.
See Prime
#each for more details.
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.
See IO.readlines
for details about getline_args.
If no block is given, an enumerator is returned instead.
print "Example one\n" "hello\nworld".each_line {|s| p s} print "Example two\n" "hello\nworld".each_line('l') {|s| p s} print "Example three\n" "hello\n\n\nworld".each_line('') {|s| p s}
produces:
Example one "hello\n" "world" Example two "hel" "l" "o\nworl" "d" Example three "hello\n\n" "world"
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
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.
Calls the block once for each value string in the database. Returns self.
Calls the block once for each key string in the database. Returns self.
Calls the block once for each [key, value] pair in the database. Returns self.
Yields the name and value of each struct member in order. If no block is given an enumerator is returned.
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.each_pair {|name, value| puts("#{name} => #{value}") }
Produces:
name => Joe Smith address => 123 Maple, Anytown NC zip => 12345
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.
Executes block for each key in the database, passing the corresponding value as a parameter.
Executes block for each key in the database, passing the key as a parameter.
Executes block for each key in the database, passing the key and the corresponding value as a parameter.
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.
Iterates over each value
in the database.
If no block is given, returns an Enumerator
.