如何拦截对Hash类的构造函数的调用?

我想在调用 Hash 类的构造函数或初始化 Hash 对象时执行函数.我已经使用

I want to execute a function when a constructor of class Hash is called or when a Hash object is initialized. I have implemented my objective using

class Hash
  def initialize
    p "Constructor call"
  end
end

当 Hash 对象按如下方式初始化时，上面的代码可以正常工作:

The code above works fine when a Hash object is initialized as follows:

a = Hash.new(:a1 => "Hi")

但是，当我使用以下代码时:

However, when I use the following code:

a = {:a1 => "Hi"}

然后，它失败或未调用构造函数.那么，如何拦截第二个代码片段中的调用?

Then, it fails or the constructor is not called. So, how to intercept the call made in the second code snippet?

提前致谢.