More ruby scope bewares

variable_scope.rb

class A
  def foo
    1
  end
  
  def beware_1
    puts "beware_1"
    
    p foo # -> 1
    foo = foo
    p foo # -> nil
  end
  
  def beware_2
    puts "beware_2"
    
    p defined? haa # -> nil
    if false
      haa = 2
    end
    p defined? haa # -> "local-variable"
  end
  
  def beware_3
    puts "beware_3"
    
    if false
      @boo = 2
    end
    p defined? @boo # -> nil
    @boo = 2
    p defined? @boo # -> "instance-variable"
  end
end

A.new.beware_1
A.new.beware_2
A.new.beware_3