将结构体作为参数传递给函数，并返回相应结构体的切片

Question

I am trying to write a function which can be used by different structs. The return of the function has to be a slice of the corresponding struct. Thus I need a function which accept a struct as a parameter and return a slice. My code somehow looks like this but I have no idea how can I wrap it as a function?

type name struct{
   FirstName string `xml:"firstName"`
   LastName string `xml:"lastName"`
  }

fileList := TreeTraversal(".")
    var a name
    var b []name 


for i := 0; i < len(fileList); i++{
    fileByte, _ := ioutil.ReadFile(fileList[i])

    xml.Unmarshal(fileByte, &a)
    b = append(b, a)
}

As far as I know I can pass a struct to a function as an interface, but I have no idea about the return type?

Answer 1

If you want a function that takes any struct type and returns a slice of it, like:

func MakeSlice(s ANY_STRUCT_TYPE) []ANY_STRUCT_TYPE

You're looking for generics, which Go doesn't currently support. See this FAQ entry.

The Go team is working to add generics to the language - it's a work in progress, and everyone is free to participate in the discussion. Once generics exist, they will provide the solution you seek here.

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In the meantime, you could use code generation or think of a slightly different design for your problem. Some code duplication is OK too, Go doesn't frown upon it as badly as some other languages.