arrow-core/arrow.core/singleOrNone

singleOrNone

fun <T> Iterable<T>.singleOrNone(): Option<T>(source)

Returns single element as Some(element), or None if the iterable is empty or has more than one element.

inline fun <T> Iterable<T>.singleOrNone(predicate: (T) -> Boolean): Option<T>(source)

Returns the single element as Some(element) matching the given predicate, or None if element was not found or more than one element was found.