}
  }

  private static <T extends @Nullable Object> void successor(AvlNode<T> a, AvlNode<T> b) {
    a.succ = b;
    b.pred = a;
  }

  private static <T extends @Nullable Object> void successor(
      AvlNode<T> a, AvlNode<T> b, AvlNode<T> c) {
    successor(a, b);
    successor(b, c);
  }

  /*

    values[size] = value;

    insertIntoTableKToV(size, keyHash);
    insertIntoTableVToK(size, valueHash);

    int successor =
        (predecessor == ENDPOINT) ? firstInInsertionOrder : nextInInsertionOrder[predecessor];
    setSucceeds(predecessor, size);
    setSucceeds(size, successor);
    size++;
    modCount++;
    return null;
  }

  /**

	// Memory Ordering Instructions
	FENCE		X1, R				// ERROR "invalid FENCE predecessor operand"
	FENCE		R, X2				// ERROR "invalid FENCE successor operand"
	FENCE		$1, R				// ERROR "invalid FENCE predecessor operand"
	FENCE		R, $2				// ERROR "invalid FENCE successor operand"
	FENCE.TSO	R, R				// ERROR "FENCE.TSO must not have operands"

	//
	// "V" Standard Extension for Vector Operations, Version 1.0
	//

Then APIStar stopped to exist as a server and Starlette was created, and was a new better foundation for such a system. That was the final inspiration to build **FastAPI**.

I consider **FastAPI** a "spiritual successor" to APIStar, while improving and increasing the features, typing system, and other parts, based on the learnings from all these previous tools.

///

## Used by **FastAPI** { #used-by-fastapi }

 *       order)
 * </ul>
 *
 * <p>{@code ValueGraph}s built by this class also guarantee that each collection-returning accessor
 * returns a <b>(live) unmodifiable view</b>; see <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#accessor-behavior">the external
 * documentation</a> for details.
 *
 * <p>Examples of use:
 *
 * {@snippet :
 * // Building a mutable value graph

 *       order)
 * </ul>
 *
 * <p>{@code Graph}s built by this class also guarantee that each collection-returning accessor
 * returns a <b>(live) unmodifiable view</b>; see <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#accessor-behavior">the external
 * documentation</a> for details.
 *
 * <p>Examples of use:
 *
 * {@snippet :
 * // Building a mutable graph

  }

  private static final class NodeAndRemainingSuccessors<N> {
    final N node;

    /**
     * The successors left to be visited, or {@code null} if we just added this {@code
     * NodeAndRemainingSuccessors} instance to the stack. In the latter case, we'll compute the
     * successors if we determine that we need them after we've performed the initial processing of
     * the node.
     */

            if (next != null) {
              Iterator<? extends N> successors = successorFunction.successors(next).iterator();
              if (successors.hasNext()) {
                // BFS: horizon.addLast(successors)
                // Pre-order: horizon.addFirst(successors)
                order.insertInto(horizon, successors);
              }
              return next;
            }

 * which has a method {@code getChildren()} that retrieves its successors in a graph:
 *
 * {@snippet :
 * someGraphAlgorithm(startNode, MyNode::getChildren);
 * }
 *
 * <p>If you have some other mechanism for returning the successors of a node, or one that doesn't
 * return an {@code Iterable<? extends N>}, then you can use a lambda to perform a more general

      }

      @Override
      public Set<N> predecessors(N node) {
        return AbstractNetwork.this.predecessors(node);
      }

      @Override
      public Set<N> successors(N node) {
        return AbstractNetwork.this.successors(node);
      }

      // DO NOT override the AbstractGraph *degree() implementations.
    };
  }

  @Override
  public int degree(N node) {
    if (isDirected()) {