Go结构中布尔的三元态（JSON标记）

type Foo struct {
    ID        string  `json:"id"
    Condition bool    `json:"condition,omitempty"`
}

I would like to json.Marshal the Foo struct above but the Condition field should have three states. For example if I do the JSON marshaling:

1)

foo := Foo {
    ID:        "one",
    Condition: true,
}

should turn into json: {id:"one","condition":true}

2)

foo := Foo {
    ID:        "two",
    Condition: false,
}

should turn into json: {id:"two","condition":false}

3)

foo := Foo {
    ID:        "three",
}

should turn into json: {id:"three"}

Currently, if I do 2), the marshaled json will be {"id":"two"} instead of {"id":"two,"condition":false} because the zero value of bool is false.

One solution is to construct my struct to use the type of *bool instead, like this:

type Foo struct {
    ID        string  `json:"id"
    Condition *bool   `json:"condition,omitempty"`
}

Is that the idiomatic way of differentiating between non-existent bool and false bool in Go?