theEagles

摘要： Mutable 关键词的作用是：可以在常函数中被修改其值。Mutable适用的场合极少，因此当你觉得你需要使用该关键词时，请再三思考！下面列出几种Mutable适用的场合：1. You have a constant object, but for debugging purposes want to track how often a constant method is called on it. Logically you're not changing the object. Note that if you're making decisions in your pr 阅读全文