fun main(args : Array<String>){ } fun ifElseNull(){ //safe call operator ?. val text: String? = null val textLength = if (text != null) text.length else 7 println(textLength) } //elvis operator ?: fun elvisOperator(){ val text: String? = "okkk" val textLength = text?.length ?: 7 } // non-null assertion fun nonNullAssert(){ val text: String? = null //null pointer exeption val textLength = text!!.length println(textLength) }