How can I write an enum with "intellisence support"? - go

Question

In go you can write an enum like this
type Direction int
const (
North Direction = iota
South
East
West
)
func main() {
// Declaring a variable myDirection with type Direction
var myDirection Direction
myDirection = West
if (myDirection == West) {
fmt.Println("myDirection is West:", myDirection)
}
}
Now image you write an enum which not only has 4 option, but instead 100. What I want is an enum that gives me "Inellisence support": If I type the enum, type a ., I want to know what options are there for the enum.
An example how this could look like is this. Is there a better way?
type direction struct{}
func (d *direction) north() string {
return "north"
}
func (d *direction) east() string {
return "east"
}
func (d *direction) south() string {
return "south"
}
func (d *direction) west() string {
return "west"
}
func main() {
var d direction
d.east()
...
}

Answer 1

I suggest to start the names of the enum values with a common prefix, e.g. Dir like this:
const (
DirNorth Direction = iota
DirSouth
DirEast
DirWest
)
Doing so, when you type packagename.Dir, you'll get a list of the possible values.
So beside applying a good naming strategy, you'll get improved auto-completion at the same time, and your source code becomes more readable (especially if there are a lot of enum values and you have more common words among them).
This is also used by the standard library, great examples are in the net/http package:
const (
MethodGet = "GET"
MethodHead = "HEAD"
MethodPost = "POST"
// ...
)
const (
StatusContinue = 100 // RFC 7231, 6.2.1
StatusSwitchingProtocols = 101 // RFC 7231, 6.2.2
StatusProcessing = 102 // RFC 2518, 10.1
StatusOK = 200 // RFC 7231, 6.3.1
StatusCreated = 201 // RFC 7231, 6.3.2
// ...
)
See related question: Glued acronyms and golang naming convention