Rob Pike _在 _ 《Errors are values》_一文中专门做了解释。其中特别强调： _Errors 是值类型 值可以编程，由于error就是一个值，因此它可以编程处理。当然，一个涉及error值的常见语句是判断它是否为零值，但对于error还有无数其他事情可以做，应用其中一些其他事情可以使程序变得更好，从而消除大部分用if语句检查每个
and that error would also include the file and line of the openfile function. Similarly, readconfig‘s wrapped error would be annotated with read config failed as well as the file and line of the call to errors.Wrapinside the readconfig function. ...
延伸阅读: https://blog.golang.org/error-handling-and-go https://blog.golang.org/errors-are-values https://blog.golang.org/go1.13-errors https://golang.org/doc/tutorial/handle-errors https://medium.com/rungo/error-handling-in-go-f0125de052f0 https://www.digitalocean.com/community/tutor...
everywhere or asking the client to check for an error after every token. It's programming with error values. Simple programming, yes, but programming nonetheless. It's worth stressing that whatever the design, it's critical that the program check the errors however they are exposed. The discus...
使用errors.New() // New returns an error that formats as the given text. // Each call to New returns a distinct error value even if the text is identical. funcNew(textstring)error{ return&errorString{text} } // errorString is a trivial implementation of error. ...
Golang 错误处理最让人头疼的问题就是代码里充斥着「if err != nil」,它们破坏了代码的可读性,本文收集了几个例子,让大家明白如何优化此类问题。 让我们看看Errors are values中提到的一个 io.Writer 例子: 代码语言:javascript 代码运行次数:0 运行
Values can be programmed, and since errors are values, errors can be programmed. Of course a common statement involving an error value is to test whether it is nil, but there are countless other things one can do with an error value, and application of some of those other things can make...
m.Currency.EqualTo(other.Currency) { return Money{}, errors.New("currencies must be identica...
values里面存放的可以是被注入struct的字段类型和值,也可以是函数实参的类型和值。注意values是以reflect.Type为Key的map,如果一个结构的字段类型相同,则后面注入的参数会覆盖前面的参数,规避的方法是使用MapTo方法,通过抽象出一个接口类型来避免覆盖。 InterfaceOf 方法虽然只有几句实现代码,但它是 Injector 的核心。
The golang idiom for testing errors against sentinel values or type checking them doesn't work with merry errors, since they are wrapped. Use Is() for sentinel value checks, or the new go 2 errors.As() function for testing error types. err := Parse() // sentinel value check if merry...