arkivanov/java_invariance_in_kotlin_2.kt

## java_invariance_in_kotlin_2.kt
fun bar(source: Observable<out CharSequence>) {
    source.scan { a, b -> "$a,$b" } // Compilation error
}

fun foo(source: Observable<String>) {
    bar(source)
}
	fun bar(source: Observable<out CharSequence>) {
	source.scan { a, b -> "$a,$b" } // Compilation error
	}

	fun foo(source: Observable<String>) {
	bar(source)
	}