Results for: "partition"

Methods Complex#as_json and Complex.json_create may be used to serialize and deserialize a Complex object; see Marshal.

Method Complex#as_json serializes self, returning a 2-element hash representing self:

require 'json/add/complex'
x = Complex(2).as_json      # => {"json_class"=>"Complex", "r"=>2, "i"=>0}
y = Complex(2.0, 4).as_json # => {"json_class"=>"Complex", "r"=>2.0, "i"=>4}

Method JSON.create deserializes such a hash, returning a Complex object:

Complex.json_create(x) # => (2+0i)
Complex.json_create(y) # => (2.0+4i)

Returns a JSON string representing self:

require 'json/add/complex'
puts Complex(2).to_json
puts Complex(2.0, 4).to_json

Output:

{"json_class":"Complex","r":2,"i":0}
{"json_class":"Complex","r":2.0,"i":4}

Returns whether self ends with any of the given strings.

Returns true if any given string matches the end, false otherwise:

'hello'.end_with?('ello')               #=> true
'hello'.end_with?('heaven', 'ello')     #=> true
'hello'.end_with?('heaven', 'paradise') #=> false
'тест'.end_with?('т')                   # => true
'こんにちは'.end_with?('は')              # => true

Related: String#start_with?.

Calls the given block with each successive character from self; returns self:

'hello'.each_char {|char| print char, ' ' }
print "\n"
'тест'.each_char {|char| print char, ' ' }
print "\n"
'こんにちは'.each_char {|char| print char, ' ' }
print "\n"

Output:

h e l l o
т е с т
こ ん に ち は

Returns an enumerator if no block is given.

Returns true if self contains only ASCII characters, false otherwise:

'abc'.ascii_only?         # => true
"abc\u{6666}".ascii_only? # => false

Returns the dirpath string that was used to create self (or nil if created by method Dir.for_fd):

Dir.new('example').path # => "example"

Converts a pathname to an absolute pathname. Relative paths are referenced from the current working directory of the process unless dir_string is given, in which case it will be used as the starting point. If the given pathname starts with a “~” it is NOT expanded, it is treated as a normal directory name.

File.absolute_path("~oracle/bin")       #=> "<relative_path>/~oracle/bin"

Returns true if file_name is an absolute path, and false otherwise.

File.absolute_path?("c:/foo")     #=> false (on Linux), true (on Windows)

Returns true if the named file is writable by the real user and group id of this process. See access(3).

Note that some OS-level security features may cause this to return true even though the file is not writable by the real user/group.

If file_name is writable by others, returns an integer representing the file permission bits of file_name. Returns nil otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2).

file_name can be an IO object.

File.world_writable?("/tmp")                  #=> 511
m = File.world_writable?("/tmp")
sprintf("%o", m)                              #=> "777"

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.

Iterates the given block for each element with an index, which starts from offset. If no block is given, returns a new Enumerator that includes the index, starting from offset

offset

the starting index to use

Iterates the given block for each element with an arbitrary object, obj, and returns obj

If no block is given, returns a new Enumerator.

Example

to_three = Enumerator.new do |y|
  3.times do |x|
    y << x
  end
end

to_three_with_string = to_three.with_object("foo")
to_three_with_string.each do |x,string|
  puts "#{string}: #{x}"
end

# => foo: 0
# => foo: 1
# => foo: 2

Returns the singleton class of obj. This method creates a new singleton class if obj does not have one.

If obj is nil, true, or false, it returns NilClass, TrueClass, or FalseClass, respectively. If obj is an Integer, a Float or a Symbol, it raises a TypeError.

Object.new.singleton_class  #=> #<Class:#<Object:0xb7ce1e24>>
String.singleton_class      #=> #<Class:String>
nil.singleton_class         #=> NilClass

Returns an array of the names of singleton methods for obj. If the optional all parameter is true, the list will include methods in modules included in obj. Only public and protected singleton methods are returned.

module Other
  def three() end
end

class Single
  def Single.four() end
end

a = Single.new

def a.one()
end

class << a
  include Other
  def two()
  end
end

Single.singleton_methods    #=> [:four]
a.singleton_methods(false)  #=> [:two, :one]
a.singleton_methods         #=> [:two, :one, :three]

Returns an array of instance variable names for the receiver. Note that simply defining an accessor does not create the corresponding instance variable.

class Fred
  attr_accessor :a1
  def initialize
    @iv = 3
  end
end
Fred.new.instance_variables   #=> [:@iv]

Similar to method, searches singleton method only.

class Demo
  def initialize(n)
    @iv = n
  end
  def hello()
    "Hello, @iv = #{@iv}"
  end
end

k = Demo.new(99)
def k.hi
  "Hi, @iv = #{@iv}"
end
m = k.singleton_method(:hi)
m.call   #=> "Hi, @iv = 99"
m = k.singleton_method(:hello) #=> NameError

Returns true if obj responds to the given method. Private and protected methods are included in the search only if the optional second parameter evaluates to true.

If the method is not implemented, as Process.fork on Windows, File.lchmod on GNU/Linux, etc., false is returned.

If the method is not defined, respond_to_missing? method is called and the result is returned.

When the method name parameter is given as a string, the string is converted to a symbol.

See as_json.

Methods Exception#as_json and Exception.json_create may be used to serialize and deserialize a Exception object; see Marshal.

Method Exception#as_json serializes self, returning a 2-element hash representing self:

require 'json/add/exception'
x = Exception.new('Foo').as_json # => {"json_class"=>"Exception", "m"=>"Foo", "b"=>nil}

Method JSON.create deserializes such a hash, returning a Exception object:

Exception.json_create(x) # => #<Exception: Foo>

Returns a JSON string representing self:

require 'json/add/exception'
puts Exception.new('Foo').to_json

Output:

{"json_class":"Exception","m":"Foo","b":null}

Return a list of the local variable names defined where this NameError exception was raised.

Internal use only.

Invoked as a callback whenever a constant is assigned on the receiver

module Chatty
  def self.const_added(const_name)
    super
    puts "Added #{const_name.inspect}"
  end
  FOO = 1
end

produces:

Added :FOO

Creates an accessor method to allow assignment to the attribute symbol.id2name. String arguments are converted to symbols. Returns an array of defined method names as symbols.

Checks for a constant with the given name in mod. If inherit is set, the lookup will also search the ancestors (and Object if mod is a Module).

The value of the constant is returned if a definition is found, otherwise a NameError is raised.

Math.const_get(:PI)   #=> 3.14159265358979

This method will recursively look up constant names if a namespaced class name is provided. For example:

module Foo; class Bar; end end
Object.const_get 'Foo::Bar'

The inherit flag is respected on each lookup. For example:

module Foo
  class Bar
    VAL = 10
  end

  class Baz < Bar; end
end

Object.const_get 'Foo::Baz::VAL'         # => 10
Object.const_get 'Foo::Baz::VAL', false  # => NameError

If the argument is not a valid constant name a NameError will be raised with a warning “wrong constant name”.

Object.const_get 'foobar' #=> NameError: wrong constant name foobar