is
Returns true if this nullable char sequence is either null or empty.
Samples
import samples.*
import java.util.Locale
import kotlin.test.*
fun main() {
//sampleStart
fun markdownLink(title: String?, url: String) =
if (title.isNullOrEmpty()) url else "[$title]($url)"
// plain link
assertPrints(markdownLink(title = null, url = "https://kotlinlang.org"), "https://kotlinlang.org")
// link with custom title
assertPrints(markdownLink(title = "Kotlin Language", url = "https://kotlinlang.org"), "[Kotlin Language](https://kotlinlang.org)")
//sampleEnd
}