我想实现一个 errors.New 版本，它接受与 fmt.Sprintf 相同的参数为此，我编写了以下函数:

func NewError(format string, a ...interface{}) error {
    return errors.New(fmt.Sprintf(format, a))
}

然而，a 成为 NewError() 内的单个数组参数，从而导致 Sprintf() 在格式字符串。如何强制将 a 解释为可变数量的参数？

最佳答案

fmt.Errorf已经做了你想做的事。看its source ，您可以看到出了什么问题:

// Errorf formats according to a format specifier and returns the string
// as a value that satisfies error.
func Errorf(format string, a ...interface{}) error {
        return errors.New(Sprintf(format, a...))
}

请注意，您的代码在 a 之后缺少 ...。来自 the spec :

Passing arguments to ... parameters

If the final argument is assignable to a slice type []T, it may be passed unchanged as the value for a ...T parameter if the argument is followed by .... In this case no new slice is created.

Given the slice s and call

s := []string{"James", "Jasmine"}
Greeting("goodbye:", s...)

within Greeting, who will have the same value as s with the same underlying array.

https://stackoverflow.com/questions/26957910/