func check(F interface{}) bool {
    errorInterface  := reflect.TypeOf((*error)(nil)).Elem()
    if tpFunc := reflect.TypeOf(Func); tpFunc.Kind() != reflect.Func {
        return false
    } else if tpFunc.NumIn() != 1 || tpFunc.NumOut() != 1 {
        return false
    } else if tpArg := tpFunc.In(0); tpArg.Kind() != reflect.Ptr || tpArg.Elem().Kind() != reflect.Struct {
        return false
    } else if tpRet := tpFunc.Out(0); tpRet.Implements(errorInterface)  {
        return false
    }
    return true
}



type T0 struct {
   A int64
   B float
}

func F0(t *T0) error {
  ...
}

func F1(t *T0) int {
  ...
}