Examples of defining methods and getting and setting instance variables on objects

object.rb

foo = Object.new

def foo.value
  42
end

foo.value
#=> 42

bar = Object.new

class << bar
  def value
    43
  end
end

bar.value
#=> 43

baz = Object.new

def baz.value
  @value
end

baz.instance_variable_set(:@value, 44)
baz.value
#=> 44

wombat = Object.new

wombat.instance_variable_set(:@value, 45)
wombat.instance_variable_get(:@value)
#=> 45