我总是必须返回一个值，即使出错

Question

If I have a function that looks like this

  func ThisIsMyComplexFunc() (ComplexStruct, error)

where ComplexStruct is a big struct that usually contain loads of values.

What if the function stumbles on an error right in the beginning, before I even started building my struct, ideally I would like to only return the error, e.g.

  return nil, err

but it wont let me do it, it forces me to create a dummy complex struct and return that together with the error, even though I never want to use the struct.

Is there a way around this?

Answer 1

If your function is declared to return two values, then you will need to return two values.

One option that might simplify your code is to use named return values:

func ThisIsMyComplexFunc() (s ComplexStruct, err error) {
    ...
}

Now you can just assign to s and/or err and then use a bare return statement. You will still be returning a ComplexStruct value, but you don't need to initialise it manually (it will default to a zero value).