Go语言的创造者写道:

Go doesn't provide assertions. They are undeniably convenient, but our experience has been that programmers use them as a crutch to avoid thinking about proper error handling and reporting. Proper error handling means that servers continue operation after non-fatal errors instead of crashing. Proper error reporting means that errors are direct and to the point, saving the programmer from interpreting a large crash trace. Precise errors are particularly important when the programmer seeing the errors is not familiar with the code.

你对此有什么看法?


当前回答

不,去做和断言都不是坏事。但两者都可能被误用。

Assert用于完整性检查。如果它们不正确,就会杀死程序。不是为了验证或替换错误处理。

其他回答

Assert被滥用用于错误处理,因为它的输入更少。

因此,作为语言设计者,他们应该看到,适当的错误处理可以用更少的输入完成。因为异常机制太冗长而排除assert并不是解决方案。哦,等等,Go也没有异常。太糟糕了:)

与其说是坏事,不如说是适得其反。永久性错误检查和调试是分开的。Assert让人们认为所有的调试都应该是永久性的,使用过多会导致大量的可读性问题。在需要时,永久错误处理应该比这种方法更好,由于assert会导致自己的错误,因此这是一种非常值得怀疑的实践。

不,只要您按照预期使用assert,它就没有错。

也就是说,它应该用于在调试期间捕捉“不可能发生”的情况,而不是正常的错误处理。

断言:程序逻辑本身的失败。 错误处理:错误的输入或系统状态,不是由于程序中的错误造成的。

我对这些捍卫assert的答案的问题是,没有人清楚地说明它与常规致命错误的不同之处,以及为什么断言不能成为异常的子集。现在,如果异常从未被捕获,该怎么办?从命名法上看,这是一种断言吗?而且,为什么要在语言中强加一个可以引发/nothing/可以处理的异常的限制呢?

我承认使用了断言,但没有考虑适当的错误报告。然而,这并不意味着它们在正确使用时是非常有用的。

They are especially useful for if you want to follow the "Crash Early" principle. For example suppose you're implementing a reference counting mechanism. At certain locations in your code you know that the refcount should be zero or one. And also suppose that if the refcount is wrong the program won't crash immediately but during the next message loop at which point it will be difficult to find out why things went wrong. An assert would have been helpful in detecting the error closer to its origin.