Kotlin メモ : count

https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.text/count.html


大文字数を数えるダメな例 val String.upperCaseCount: Int get() = filter { it.isUpperCase() }.length

大文字数を数える良い例 val String.upperCaseCount: Int get() = count { it.isUpperCase() }