Ruby Class

Code4-7.rb

# encoding: SJIS

class Foo
  def initialize(a)
    @a = a
  end
  def method1
    @a
  end
end

class FooExt < Foo
  def initialize(a,b)
    @b = b
    super a
  end
  def method2(c)
    @a + @b + c
  end
end

p "Foo.ancestors:",    Foo.ancestors
p "FooExt.ancestors:", FooExt.ancestors

# 継承関係を判定する
p "Foo < Object" , Foo < Object
p "Foo > Object" , Foo > Object

# オブジェクトがもつインスタンスメソッド
# false : superclassを辿らない
p Foo.instance_methods(false)
p FooExt.instance_methods(false)
# 
p FooExt.instance_methods(true)

foo1 = Foo.new(1)
p foo1.instance_variables

fooE = FooExt.new(1,2)
p fooE.instance_variables

LOG

>ruby Code4-7.rb 
ruby Code4-7.rb 
"Foo.ancestors:"
[Foo, Object, Kernel, BasicObject]
"FooExt.ancestors:"
[FooExt, Foo, Object, Kernel, BasicObject]
"Foo < Object"
true
"Foo > Object"
false
[:method1]
[:method2]
[:method2, :method1, :nil?, :===, :=~, :!~, :eql?, :hash, :<=>, :class, :singleton_class, :clone, :dup, :taint, :tainted?, :untaint, :untrust, :untrusted?, :trust, :freeze, :frozen?, :to_s, :inspect, :methods, :singleton_methods, :protected_methods, :private_methods, :public_methods, :instance_variables, :instance_variable_get, :instance_variable_set, :instance_variable_defined?, :remove_instance_variable, :instance_of?, :kind_of?, :is_a?, :tap, :send, :public_send, :respond_to?, :extend, :display, :method, :public_method, :singleton_method, :define_singleton_method, :object_id, :to_enum, :enum_for, :==, :equal?, :!, :!=, :instance_eval, :instance_exec, :__send__, :__id__]
[:@a]
[:@b, :@a]