是否有充分的理由说明在函数中只有一个return语句是一个更好的实践?

或者在逻辑上正确的情况下,可以从函数中返回,这意味着函数中可能有许多返回语句?


当前回答

I've seen it in coding standards for C++ that were a hang-over from C, as if you don't have RAII or other automatic memory management then you have to clean up for each return, which either means cut-and-paste of the clean-up or a goto (logically the same as 'finally' in managed languages), both of which are considered bad form. If your practices are to use smart pointers and collections in C++ or another automatic memory system, then there isn't a strong reason for it, and it become all about readability, and more of a judgement call.

其他回答

唯一重要的问题是“如何使代码更简单、更易读、更容易理解?”如果使用多个返回会更简单,那么就使用它们。

总是要求单一的返回类型是没有意义的。我认为这更像是一个标志,表明某些东西可能需要简化。有时有多个回报是必要的,但通常你可以通过至少尝试有一个退出点来简化事情。

我倾向于认为函数中间的return语句是不好的。您可以使用返回在函数的顶部构建一些保护子句,当然也可以告诉编译器在函数的末尾返回什么,但函数中间的返回很容易被忽略,并且会使函数更难解释。

Structured programming says you should only ever have one return statement per function. This is to limit the complexity. Many people such as Martin Fowler argue that it is simpler to write functions with multiple return statements. He presents this argument in the classic refactoring book he wrote. This works well if you follow his other advice and write small functions. I agree with this point of view and only strict structured programming purists adhere to single return statements per function.

我通常支持多个return语句。它们是最容易阅读的。

在某些情况下,这并不好。有时从函数返回可能非常复杂。我记得有一种情况,所有函数都必须链接到多个不同的库。一个库期望返回值是错误/状态代码,而其他库则不期望。使用一个return语句可以节省时间。

我很惊讶没人提到goto。Goto并不是每个人都想让你相信的编程的祸害。如果必须在每个函数中只有一个return语句,请将它放在末尾,并根据需要使用gotos跳转到该return语句。绝对避免标记和箭头编程,它们既丑陋又运行缓慢。