ifBlank
inline fun <C, R> C.ifBlank(
defaultValue: () -> R
): R where C : CharSequence, C : R
Returns this char sequence if it is not empty and doesn't consist solely of whitespace characters, or the result of calling defaultValue function otherwise.
import kotlin.test.*
fun main(args: Array<String>) {
//sampleStart
val blank = " "
val blankOrNull: String? = blank.ifBlank { null }
println(blankOrNull) // null
val blankOrDefault = blank.ifBlank { "default" }
println(blankOrDefault) // default
val nonBlank = "abc"
val sameString = nonBlank.ifBlank { "def" }
println("nonBlank === sameString is ${nonBlank === sameString}") // true
//sampleEnd
}