首先，静态并不是 Ruby行话的真正组成部分。

First off, static is not really part of the Ruby jargon.

让我们举一个简单的例子：

Let's take a simple example:

class Bar
  def self.foo
  end
end

它定义了方法 foo 放在显式对象 self 上，该对象在该范围内返回包含类 Bar 。
是的，可以将其定义为 class方法，但是 static 在Ruby中实际上没有意义。

It defines the method foo on an explicit object, self, which in that scope returns the containing class Bar. Yes, it can be defined a class method, but static does not really make sense in Ruby.

然后 private 不起作用，因为在显式对象上定义方法（例如 def self.foo ）

Then private would not work, because defining a method on an explicit object (e.g. def self.foo) bypasses the access qualifiers and makes the method public.

您可以做的是使用 class<<。 self 语法来打开包含类的元类，并将其中的方法定义为实例方法：

What you can do, is to use the class << self syntax to open the metaclass of the containing class, and define the methods there as instance methods:

class Foo
  class << self

    def bar
      do_calc
    end

    def baz
      do_calc
    end

    private

    def do_calc
      puts "calculating..."
    end
  end
end

这将为您提供所需的内容。

This will give you what you need:

Foo.bar
calculating...

Foo.baz
calculating...

Foo.do_calc
NoMethodError: private method `do_calc' called for Foo:Class