package main import ( "encoding/json" "fmt" "github.com/ykalchevskiy/poly" ) type IsAction interface {	poly.TypeName // just for convenience IsAction() } type ActionDismiss struct{} func (ActionDismiss) IsAction() {} func (ActionDismiss) TypeName() string { return "dismiss" } type ActionDeepLink struct { URL string `json:"url"` } func (ActionDeepLink) IsAction() {} func (ActionDeepLink) TypeName() string { return "deep-link" } type Action = poly.Poly[IsAction, poly.Types2[ActionDismiss, ActionDeepLink]] func main() { var action Action var bytes []byte _ = json.Unmarshal([]byte(`{"type":"dismiss"}`), &action) fmt.Printf("%T\n", action.Value) // ActionDismiss bytes, _ = json.Marshal(action) fmt.Println(string(bytes)) // {"type":"dismiss"} _ = json.Unmarshal([]byte(`{"type":"deep-link","url":"url1"}`), &action) fmt.Printf("%T\n", action.Value) // ActionDeepLink bytes, _ = json.Marshal(action) fmt.Println(string(bytes)) // {"type":"deep-link","url":"url1"} // patch the existing ActionDeepLink _ = json.Unmarshal([]byte(`{"url":"url2"}`), &action) bytes, _ = json.Marshal(action) fmt.Println(string(bytes)) // {"type":"deep-link","url":"url2"} }