Go中的可打印枚举

Question

In some cases, it's convenient for user interaction and debugging purposes to have a human-readable string representation of enums. So far, the best I have come up with is:

type ElementType int

const (
    Fire = ElementType(iota)
    Air
    Water
    Earth
)

var elementTypeMap = map[ElementType]string{
    Fire: "The Fiery Fire",
    Air: "The Airy Air",
    Water: "The Watery Water",
    Earth: "The Earthy Earth",
}

func (el ElementType) String() string {
    return elementTypeMap[el]
}

The above, allows me to use and pass the enum as an int, keeping its standard performance, and to easily print its string representation anywhere. The only drawback is that there is an amount of boilerplate code that adds up if you have many enum types: I would be rather happy to avoid it.

Is there a way, preferably an idiomatic one, to reduce the boilerplate code above?

Answer 1

This looks dryer (and faster) :

type ElementType int

const (
    Fire = ElementType(iota)
    Air
    Water
    Earth
)

var elementnames = [...]string {
    "The Fiery Fire",
    "The Airy Air",
    "The Watery Water",
    "The Earthy Earth"
}

func (el ElementType) String() string {
    return elementnames[el]
}

Note that there was a discussion on golang-nuts on whether giving a generic solution to assign names to enum constants and as far as I know it wasn't seen as necessary (see https://groups.google.com/forum/#!topic/golang-nuts/fCdBSRNNUY8).