Hello, I encountered an unexpected behaviour it th...

# compiler

[Paulius Ruminas]

Hello,
I encountered an unexpected behaviour it this code snippet:

interface Command<T>
    
class TestUnitCommand : Command<Unit>

class TestIntCommand : Command<Int>
    
class TestStringCommand : Command<String>
    
class Result<T>
    
inline fun <reified T : Command<R>, reified R : Any> execute(crossinline block: suspend (T) -> R) {}

fun main() {
    execute<TestUnitCommand, Unit> { Result<Unit>() }        // OK
    execute<TestIntCommand, Int> { Result<Int>() }           // Error
    execute<TestStringCommand, String> { Result<String>() }  // Error
}

Why does it not error when Command generic parameter is Unit? Does it implicitly not return anything?

[karelpeeters]

Yes, lambdas do implicitly return Unit, that's the point.

[Paulius Ruminas]

Okay, makes sense

[karelpeeters]

(also for next time, these kinds of questions don't belong in #compiler, use #general or #getting-started instead)

[Paulius Ruminas]

Sorry, my bad