hey, can I have this?

sealed inline class Token{}
object UnixNewline: Token()
object WindowsNewline: Token()
inline class Character(val impl: Char): Token()

it would make one of my tokenizers run a whole lot faster

inline classes need a single value parameter, that sealed class doesn’t have one and therefore can’t be inline

right but its abstract

so what do you expect the inline modifier on the sealed class to actually do?

1. erase the type from reflection 2. let me use an

inline class

as a type in a

when

expression with exhaustive coverage

you expect an abstract class to be erased from reflection? that’s not realistically possible

presumably we can use the same boxing device as:

interface Whatever{}
inline class MyImpl(val char: impl): Whatever

fun myFunc(p1: Whatever){

yes, but

Whatever

can’t be inlined, and if i’m not mistaken, a function accepting

Whatever

has to accept a boxed (i.e.

MyImpl

) value rather than an

impl

I mean im not actually concerned with the runtime incarnation of

Whatever

, but if your point is that boxing is going to cause me to see those object allocations regardless then I'm stuck. Presumably if I express my tokenizer as a set of static functions and/or inline functions, then the object allocations go away?

Everytime you call a function/method that requires a

Whatever

, auto-boxing is involved

That wouldn't be erased by either an optimization pass nor the jitter?

interface Whatever {}
inline class Impl(val value: Char)

inline fun Whatever.doSomething() = when(this) {
  is Whatever -> value
  else -> '0'
}

fun something(){
  val x: Impl = Impl('1')
  val y = x.doSomething()
}

is going to involve allocating a boxed

ImplAsWhatever

?

Whatever.doSomething()

might have to cast to

Whatever

, meaning yes(?)

You'd need a pretty sophisticated compiler optimization to remove it, and I dont think the jitter would be willing to assume that the object allocation chain (which to it is of course quite large) wouldn't cause some other behaviour somewhere (static initialization of

Whatever

for example?).

just decompiled the example you gave, it boxes before calling

doSomething

whats the decompilation tool your using? I saw somebody posting a plugin for intelliJ that looked pretty good.

just the basic one in IntelliJ

thanks @serebit!

👍🏿 no problem