方法
实例公共方法
duplicable?() 链接
Singleton 实例不可复制
Class.new.include(Singleton).instance.dup # TypeError (can't dup instance of singleton
来源: 显示 | 在 GitHub 上
# File activesupport/lib/active_support/core_ext/object/duplicable.rb, line 66 def duplicable? false end