Is there a way to call <EnumSet.noneOf()> given only a generic type parameter, let's say T? Neither ...

# getting-started

[Karlo Lozovina]

Is there a way to call EnumSet.noneOf() given only a generic type parameter, let's say T? Neither noneOf(T::class.java), noneOf(T::class) work. If I pass around a value, then everything works fine (noneOf(value::class.java)), but is there a way to keep everything on the type level?

[Rob Elliot]

You could use a reified function:
inline fun <reified T : Enum<T>> noneOf(): EnumSet<T> = EnumSet.noneOf(T::class.java)

[Rob Elliot]

val x = noneOf<MyEnum>()

[Karlo Lozovina]

Thanks, figured that one in the end. But still, I'd like to use it as a class property, and there are no reified classes...

[Karlo Lozovina]

I ended up just passing an extra value to the class, no big deal, just wondered if it could be done without it

[Paul Griffith]

If you just care about use-site convenience and don’t mind squinting a bit, you could have a “constructor” function for your class that’s actually inline reified - if you give it the same name as the class you can use it transparently
https://pl.kotl.in/MF7-JYB83

[Rob Elliot]

My preference would be an operator fun invoke on a companion object:
https://pl.kotl.in/0pmoOuZ8C

[Karlo Lozovina]

@Rob Elliot wow, that's pretty cute & clever! didn't know I could overload the invoke operator 😄. Maybe a bit too clever, but it's a small codebase, why not go wild a bit! 😄