Functional Options In Go

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I wrote a thing if you care:

https://hooks.technology/2020/08/functional-options/

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So here's a playground example of using functional options and error handling: https://play.golang.org/p/cfw7axv6pjO

The advantage over method chaining is that we can return our errors correctly this way. Using the following as an example, I can return my error the whole way to the function call in main() and only need to handle it in a single place.

type MethodOption func(*http.Request) (*http.Request, error)

func NewRequest(opt ...MethodOption) (*http.Request, error) {
	r := &http.Request{}
	var err error

	for _, opt := range opt {
		r, err = opt(r)
		if err != nil {
		   return nil, err
		}
	}
	

	return r, nil
}

func SetURL(URL string) MethodOption {
	return func(r *http.Request) (*http.Request, error) {
		u, err := url.Parse(URL)
		if err != nil {
			return nil, err
		}
		r.URL = u
		return r, nil
	}
}

	req, err := NewRequest(
		SetURL("https://google.com"),
	)
	if err!= nil {
		fmt.Println(err)
		os.Exit(1)
	}