class OpenStruct


of these properties compared to using a Hash or a Struct.
the objects that are created, as there is much more overhead in the setting
This should be a consideration if there is a concern about the performance of
method_missing and define_singleton_method.
necessary methods for properties. This is accomplished through the methods
An OpenStruct utilizes Ruby’s method lookup structure to find and define the
== Implementation
first_pet == second_pet # => true
first_pet # => #<OpenStruct name=“Rowdy”>
first_pet.delete_field(:owner)
first_pet == second_pet # => false
first_pet # => #<OpenStruct name=“Rowdy”, owner=nil>
first_pet.owner = nil
second_pet = OpenStruct.new(:name => “Rowdy”)
first_pet = OpenStruct.new(:name => “Rowdy”, :owner => “John Smith”)
remove the attribute.
delete_field method as setting the property value to nil will not
Removing the presence of an attribute requires the execution of the
message.queued? # => false
message.send(“queued?=”, false)
message.queued? # => true
message = OpenStruct.new(:queued? => true)
measurements.send(“length (in inches)”) # => 24
measurements = OpenStruct.new(“length (in inches)” => 24)
still be reached through the Object#send method.
on the OpenStruct object as a method for retrieval or assignment, but can
method calls (e.g. ()[]*) will not be immediately available
Hash keys with spaces or characters that could normally not be used for
# => #<OpenStruct country=“Australia”, capital=“Canberra”>
australia = OpenStruct.new(:country => “Australia”, :capital => “Canberra”)
and can even be initialized with one:
An OpenStruct employs a Hash internally to store the attributes and values
person.address # => nil
person.age # => 70
person.name # => “John Smith”
person.age = 70
person.name = “John Smith”
person = OpenStruct.new
require “ostruct”
== Examples
itself.
accomplished by using Ruby’s metaprogramming to define methods on the class
definition of arbitrary attributes with their accompanying values. This is
An OpenStruct is a data structure, similar to a Hash, that allows the

def ==(other)


first_pet == third_pet # => false
first_pet == second_pet # => true

third_pet = OpenStruct.new("name" => "Rowdy", :age => nil)
second_pet = OpenStruct.new(:name => "Rowdy")
first_pet = OpenStruct.new("name" => "Rowdy")
require "ostruct"

equal.
+other+ when +other+ is an OpenStruct and the two objects' Hash tables are
Compares this object and +other+ for equality. An OpenStruct is equal to
def ==(other)
  return false unless other.kind_of?(OpenStruct)
  @table == other.table!
end

def [](name)


person[:age] # => 70, same as person.age
person = OpenStruct.new("name" => "John Smith", "age" => 70)
require "ostruct"

Returns the value of an attribute.

ostruct[name] -> object
:call-seq:
def [](name)
  @table[name.to_sym]
end

def []=(name, value)


person.age # => 42
person[:age] = 42 # equivalent to person.age = 42
person = OpenStruct.new("name" => "John Smith", "age" => 70)
require "ostruct"

Sets the value of an attribute.

ostruct[name] = obj -> obj
:call-seq:
def []=(name, value)
  modifiable?[new_ostruct_member!(name)] = value
end

def delete_field(name)


person # => #
person.pension = nil

Setting the value to +nil+ will not remove the attribute:

person # => #
person.delete_field("age") # => 70

person = OpenStruct.new(name: "John", age: 70, pension: 300)

require "ostruct"

contained if it was defined.
Removes the named field from the object. Returns the value that the field
def delete_field(name)
  sym = name.to_sym
  begin
    singleton_class.remove_method(sym, "#{sym}=")
  rescue NameError
  end
  @table.delete(sym) do
    raise NameError.new("no field `#{sym}' in #{self}", sym)
  end
end

def dig(name, *names)


data.dig(:array, 0, 0) # TypeError: Integer does not have #dig method
data.dig(:array, 1, 0) # => 2

data = OpenStruct.new(:array => [1, [2, 3]])

person.dig(:business_address, "zip") # => nil
person.dig(:address, "zip") # => 12345

person = OpenStruct.new("name" => "John Smith", "address" => address)
address = OpenStruct.new("city" => "Anytown NC", "zip" => 12345)
require "ostruct"

intermediate step is +nil+.
objects by calling +dig+ at each step, returning +nil+ if any
Extracts the nested value specified by the sequence of +name+

ostruct.dig(name, ...) -> object
:call-seq:
def dig(name, *names)
  begin
    name = name.to_sym
  rescue NoMethodError
    raise TypeError, "#{name} is not a symbol nor a string"
  end
  @table.dig(name, *names)
end

def each_pair


data.each_pair.to_a # => [[:country, "Australia"], [:capital, "Canberra"]]
data = OpenStruct.new("country" => "Australia", :capital => "Canberra")
require "ostruct"

or returns an enumerator if no block is given.
Yields all attributes (as symbols) along with the corresponding values

ostruct.each_pair -> Enumerator
ostruct.each_pair {|name, value| block } -> ostruct
:call-seq:
def each_pair
  return to_enum(__method__) { @table.size } unless block_given?
  @table.each_pair{|p| yield p}
  self
end

def eql?(other)


eql?.
+other+ when +other+ is an OpenStruct and the two objects' Hash tables are
Compares this object and +other+ for equality. An OpenStruct is eql? to
def eql?(other)
  return false unless other.kind_of?(OpenStruct)
  @table.eql?(other.table!)
end

def freeze 

def freeze
  @table.each_key {|key| new_ostruct_member!(key)}
  super
end

def hash

See also Object#hash.

(and will compare using #eql?).
Two OpenStruct objects with the same content will have the same hash code
Computes a hash code for this OpenStruct. 
def hash
  @table.hash
end

def initialize(hash=nil)


data # => #

data = OpenStruct.new(hash)
hash = { "country" => "Australia", :capital => "Canberra" }
require "ostruct"

For example:
(can be a Hash, an OpenStruct or a Struct).
The optional +hash+, if given, will generate attributes and values

object will have no attributes.
Creates a new OpenStruct object. By default, the resulting OpenStruct
def initialize(hash=nil)
  @table = {}
  if hash
    hash.each_pair do |k, v|
      k = k.to_sym
      @table[k] = v
    end
  end
end

def initialize_copy(orig) # :nodoc:

:nodoc:
Duplicates an OpenStruct object's Hash table. 
def initialize_copy(orig) # :nodoc:
  super
  @table = @table.dup
end

def inspect


Returns a string containing a detailed summary of the keys and values.
def inspect
  ids = (Thread.current[InspectKey] ||= [])
  if ids.include?(object_id)
    detail = ' ...'
  else
    ids << object_id
    begin
      detail = @table.map do |key, value|
        " #{key}=#{value.inspect}"
      end.join(',')
    ensure
      ids.pop
    end
  end
  ['#<', self.class, detail, '>'].join
end

def marshal_dump


Provides marshalling support for use by the Marshal library.
def marshal_dump
  @table
end

def marshal_load(x)


Provides marshalling support for use by the Marshal library.
def marshal_load(x)
  @table = x
end

def method_missing(mid, *args) # :nodoc:

:nodoc: 
def method_missing(mid, *args) # :nodoc:
  len = args.length
  if mname = mid[/.*(?==\z)/m]
    if len != 1
      raise ArgumentError, "wrong number of arguments (#{len} for 1)", caller(1)
    end
    modifiable?[new_ostruct_member!(mname)] = args[0]
  elsif len == 0 # and /\A[a-z_]\w*\z/ =~ mid #
    if @table.key?(mid)
      new_ostruct_member!(mid) unless frozen?
      @table[mid]
    end
  else
    begin
      super
    rescue NoMethodError => err
      err.backtrace.shift
      raise
    end
  end
end

def modifiable? # :nodoc:

:nodoc:

modified before granting access to the internal Hash table to be modified.
Used internally to check if the OpenStruct is able to be
def modifiable? # :nodoc:
  begin
    @modifiable = true
  rescue
    exception_class = defined?(FrozenError) ? FrozenError : RuntimeError
    raise exception_class, "can't modify frozen #{self.class}", caller(3)
  end
  @table
end

def new_ostruct_member!(name) # :nodoc:

:nodoc:

define_singleton_method for both the getter method and the setter method.
OpenStruct. It does this by using the metaprogramming function
Used internally to defined properties on the
def new_ostruct_member!(name) # :nodoc:
  name = name.to_sym
  unless singleton_class.method_defined?(name)
    define_singleton_method(name) { @table[name] }
    define_singleton_method("#{name}=") {|x| modifiable?[name] = x}
  end
  name
end

def respond_to_missing?(mid, include_private = false) # :nodoc:

:nodoc: 
def respond_to_missing?(mid, include_private = false) # :nodoc:
  mname = mid.to_s.chomp("=").to_sym
  @table&.key?(mname) || super
end

def to_h


data.to_h # => {:country => "Australia", :capital => "Canberra" }
data = OpenStruct.new("country" => "Australia", :capital => "Canberra")
require "ostruct"

each attribute (as symbols) and their corresponding values.
Converts the OpenStruct to a hash with keys representing
def to_h
  @table.dup
end