if(typeof obj_from_json !== "object" || Array.isArray(obj_from_json)){

      // not an object, stringify using native function

      return JSON.stringify(obj_from_json);

    }

    // Implements recursive object serialization according to JSON spec

    // but without quotes around the keys.

    let props = Object

      .keys(obj_from_json)

        .map(key => `${key}:${stringify(obj_from_json[key])}`)

        .join(",");

    return `{${props}}`;

}

​

var obj = {

  name: "John Smith",

    job: {

      name: "Accountant",

        salary: 1000

    },

    favortieFruits: ["Apple", "Banana"]

};

​

console.log(stringify(obj));