* that order.
 *
 * <p>By default, {@code Splitter}'s behavior is simplistic and unassuming. The following
 * expression:
 *
 * {@snippet :
 * Splitter.on(',').split(" foo,,,  bar ,")
 * }
 *
 * ... yields the substrings {@code [" foo", "", "", " bar ", ""]}. If this is not the desired
 * behavior, use configuration methods to obtain a <i>new</i> splitter instance with modified
 * behavior:
 *
 * {@snippet :

 *
 * <p>Implementations of this interface are expected to be thread-safe, and can be safely accessed
 * by multiple concurrent threads.
 *
 * <p>When evaluated as a {@link Function}, a cache yields the same result as invoking {@link
 * #getUnchecked}.
 *
 * @param <K> the type of the cache's keys, which are not permitted to be null
 * @param <V> the type of the cache's values, which are not permitted to be null

 * that order.
 *
 * <p>By default, {@code Splitter}'s behavior is simplistic and unassuming. The following
 * expression:
 *
 * {@snippet :
 * Splitter.on(',').split(" foo,,,  bar ,")
 * }
 *
 * ... yields the substrings {@code [" foo", "", "", " bar ", ""]}. If this is not the desired
 * behavior, use configuration methods to obtain a <i>new</i> splitter instance with modified
 * behavior:
 *
 * {@snippet :

 *
 * <p>Implementations of this interface are expected to be thread-safe, and can be safely accessed
 * by multiple concurrent threads.
 *
 * <p>When evaluated as a {@link Function}, a cache yields the same result as invoking {@link
 * #getUnchecked}.
 *
 * @param <K> the type of the cache's keys, which are not permitted to be null
 * @param <V> the type of the cache's values, which are not permitted to be null

	left, right *Tree[K, V]
	key         K
	value       V
}

func (t *Tree[K, V]) walk(yield func(key K, val V) bool) bool {
	return t == nil || t.left.walk(yield) && yield(t.key, t.value) && t.right.walk(yield)
}

func (t *Tree[K, V]) Walk(yield func(key K, val V) bool) {
	t.walk(yield)
}

// walk tree t in-order
var t Tree[string, int]
for k, v := range t.Walk {

  /**
   * Divides an iterable into unmodifiable sublists of the given size (the final iterable may be
   * smaller). For example, partitioning an iterable containing {@code [a, b, c, d, e]} with a
   * partition size of 3 yields {@code [[a, b, c], [d, e]]} -- an outer iterable containing two
   * inner lists of three and two elements, all in the original order.
   *

   * size (the final list may be smaller). For example, partitioning a list containing {@code [a, b,
   * c, d, e]} with a partition size of 3 yields {@code [[a, b, c], [d, e]]} -- an outer list
   * containing two inner lists of three and two elements, all in the original order.
   *

   * size (the final list may be smaller). For example, partitioning a list containing {@code [a, b,
   * c, d, e]} with a partition size of 3 yields {@code [[a, b, c], [d, e]]} -- an outer list
   * containing two inner lists of three and two elements, all in the original order.
   *

   * usually have much noticeable impact. A value of one permits only one thread to modify the cache
   * at a time, but since read operations and cache loading computations can proceed concurrently,
   * this still yields higher concurrency than full synchronization.
   *
   * <p>Defaults to 4. <b>Note:</b>The default may change in the future. If you care about this
   * value, you should always choose it explicitly.
   *

// empty slice if s contains only white space. Every element of the returned slice is
// non-empty. Unlike [Split], leading and trailing runs of white space characters
// are discarded.
func Fields(s []byte) [][]byte {
	// First count the fields.
	// This is an exact count if s is ASCII, otherwise it is an approximation.
	n := 0
	wasSpace := 1
	// setBits is used to track which bits are set in the bytes of s.
	setBits := uint8(0)