Slide 80
Slide 80 text
ifEmpty / ifBlank
Collections, Map, Array 等が空の場合の値を指定可能
fun printAllUppercase(data: List) {
val result = data
.filter { it.all { c -> c.isUpperCase() } }
.ifEmpty { listOf("") }
result.forEach { println(it) }
}
printAllUppercase(listOf("foo", "Bar")) //
printAllUppercase(listOf("FOO", "bar")) // FOO