为什么我不能在 C++ 的 `std::map` 中存储引用?

2022-01-05 00:00:00 dictionary reference c++ std stdmap

我知道引用不是指针,而是对象的别名.但是,作为程序员,我仍然不明白这对我来说究竟意味着什么,即引擎盖下的引用是什么?

I understand that references are not pointers, but an alias to an object. However, I still don't understand what exactly this means to me as a programmer, i.e. what are references under the hood?

我认为理解这一点的最好方法是理解为什么我不能在地图中存储参考.

I think the best way to understand this would be to understand why it is I can't store a reference in a map.

我知道我需要停止将引用视为对指针的句法支持,只是不知道如何:/

I know I need to stop thinking of references as syntactic suger over pointers, just not sure how to :/

推荐答案

按照我的理解,引用在幕后实现为指针.不能将它们存储在地图中的原因纯粹是语义;您必须在创建引用时对其进行初始化,之后便无法再更改它.这与地图的工作方式不符.

They way I understand it, references are implemented as pointers under the hood. The reason why you can't store them in a map is purely semantic; you have to initialize a reference when it's created and you can't change it afterward anymore. This doesn't mesh with the way a map works.

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