fun main() {
var nullTest: String? = null
}
fun testFun(s: String?): String? {
return s?.uppercase()
}
fun main() {
testFun("abcdtesttc")
testFun(null)
}
fun testFun(s: String?): String? {
return s ?: "unknown"
}
fun main() {
println(testFun("abcdtesttc"))
println(testFun(null))
}
Output
abcdtesttc
unknown
fun testFun(s: String?): Int? {
val NotNull: String = s!!
return NotNull.length
}
fun main() {
println(testFun("abcdtesttc"))
println(testFun(null))
}
Output
10
Exception in thread "main" java.lang.NullPointerException
fun testFun(s: String?): String? {
return s?.let {
"NOT NULL KKK"
}
}
fun main() {
println(testFun("testString"))
println(testFun(null))
}
Output
NOT NULL KKK
null