kotlin-stdlib/kotlin.text/singleOrNull

singleOrNull

fun CharSequence.singleOrNull(): Char?(source)

Returns single character, or null if the char sequence is empty or has more than one character.

Since Kotlin

1.0
inline fun CharSequence.singleOrNull(predicate: (Char) -> Boolean): Char?(source)

Returns the single character matching the given predicate, or null if character was not found or more than one character was found.

Since Kotlin

1.0