Ruby：定义实例变量的更短方法

Question

我正在寻找在initialize 方法中定义实例变量的更短的方法：

class MyClass
  attr_accessor :foo, :bar, :baz, :qux
  # Typing same stuff all the time is boring
  def initialize(foo, bar, baz, qux)
    @foo, @bar, @baz, @qux = foo, bar, baz, qux
  end
end

Ruby 是否有任何内置功能可以避免这种笨拙的工作？

# e. g.
class MyClass
  attr_accessor :foo, :bar, :baz, :qux
  # Typing same stuff all the time is boring
  def initialize(foo, bar, baz, qux)
    # Leveraging built-in language feature
    # instance variables are defined automatically
  end
end

Answer 1

认识Struct，专为此而生的工具！

MyClass = Struct.new(:foo, :bar, :baz, :qux) do
  # Define your other methods here. 
  # Initializer/accessors will be generated for you.
end

mc = MyClass.new(1)
mc.foo # => 1
mc.bar # => nil

我经常看到人们这样使用 Struct：

class MyStruct < Struct.new(:foo, :bar, :baz, :qux)
end

但这会导致一个额外的未使用的类对象。不需要的时候为什么要创建垃圾？