一种在Ruby中保护数据类型的方法

class Person
  def initialize(name, age)
    @name = name
    @age = age
  end

  def introduce
    puts "My name is #{@name} and I'm #{@age} years old."
  end

  def compare_age(other_person)
    if other_person.age < age
      puts "#{other_person.name} is younger than me."
    else
      puts "#{other_person.name} is older than me."
    end
  end

  protected

  def age
    @age
  end

  def name
    @name
  end
end

person1 = Person.new("Alice", 25)
person2 = Person.new("Bob", 30)

person1.introduce
person2.introduce

person1.compare_age(person2)
person2.compare_age(person1)