Ability to set enums in config

[SHaaD94]

It would be cool to have an ability to set a field which might have only limited set of values for example, let's say fruitType can be only apple, banana or pineapple.
In the config it could look like this:

app.fruitType = "string E ["apple", "banana", "pineapple"]"

After it, sealed trait with three classes could be generated:

trait FruitType 
object FruitType {
   object Apple extends FruitType
   object Banana extends FruitType
   object Pineapple extends FruitType
}

[carueda]

Adding enums would be great, thanks.

At the spec level, maybe something combined with or similar to @define (#54):

#@define enum
FruitType = [apple, banana, pineapple]

# then, somewhere for the actual use/reference:

foo: {
  fruit: FruitType,
  ...
}

[johanneshiry]

hi @SHaaD94 - are you interested in actively working to provide this feature? I handed in #64 which would make a huge benefit in several of our projects and as @carueda suggested I might make sense to talke your proposal and #64 together ...

[carueda]

@SHaaD94 / @johanneshiry : fyi, i've done some progress on this, but will have to postpone completion for a little while (the java generation seems pretty complete, but not yet the scala one, at least for enum references at the root of the given config). I realize that enhancements like this and #64 are not as "straightforward" as one would like them to be given that the code has become rather complex; I myself have to spend some time catching up with the structure of things, etc. (I wish I had more time to proceed with a general revision.) Thanks again for your suggestions and contributions, really appreciated.

[carueda]

Implemented in 0.9.983 - https://github.com/carueda/tscfg#enum