Module#attr_accessor & friends

gistfile1.rb

# Have u ever found urself doing this:

  class Thing
    def size=(size)
      @size = size
    end
    def size
      @size
    end
  end

# You can avoid doing the above by using Module#attr_accessor:

  class Thing
    attr_accessor :size
  end

  t = Thing.new
  t.size = :xl
  puts t.size # >> xl

# Module#attr_accessor is written in C, so definitely it is more
# performant. Let's say u want the writer to be accessible only
# within the instance itself, u can do the following:

  class Thing
    attr_accessor :size
    private :size=

    def cheat(size)
      self.size = size
    end
  end

  t = Thing.new
  #puts t.size = :xl # >> NoMethodError
  t.cheat(:xl)
  puts t.size        # >> xl

# Exercise: Try out Module#attr_reader & Module#attr_writer as well.

Agree.