Function first

packages/effect/src/internal/redBlackTree.ts:216–224

(self: RBT.RedBlackTree<K, V>)

/** @internal */
export const first = <K, V>(self: RBT.RedBlackTree<K, V>): Option.Option<[K, V]> => {
  let node: Node.Node<K, V> | undefined = (self as RedBlackTreeImpl<K, V>)._root
  let current: Node.Node<K, V> | undefined = (self as RedBlackTreeImpl<K, V>)._root
  while (node !== undefined) {
    current = node
    node = node.left
  }
  return current ? Option.some([current.key, current.value]) : Option.none()
}

/** @internal */
export const getAt = dual<