json go

package main

import (
   "encoding/json"
   "fmt"
)

type b struct {
   Params      []interface{}   `json:"params,omitempty"`
}

func main() {
   v := []interface{}(nil)
   v = append(v, map[string]string{"1":"a", "2":"b"})
   v = append(v, []string{"cc", "dd"})
   a := b{v}
   s, err := json.Marshal(a)
   fmt.Println(string(s), err)
}