# Dependencies with yield

FastAPI supports dependencies that do some <abbr title='sometimes also called "exit code", "cleanup code", "teardown code", "closing code", "context manager exit code", etc.'>extra steps after finishing</abbr>.

To do this, use `yield` instead of `return`, and write the extra steps (code) after.

/// tip

Make sure to use `yield` one single time per dependency.

///

/// note | "Technical Details"

track][tls_history] the dynamic TLS ecosystem and adjust OkHttp to improve connectivity and
security.

OkHttp uses your platform's built-in TLS implementation. On Java platforms OkHttp also supports
[Conscrypt][conscrypt], which integrates [BoringSSL](https://github.com/google/boringssl) with Java. OkHttp will use Conscrypt if it is
the first security provider:

```java

        if (node.children == null) {
          // Terminal node.
          sink.writeByte(node.symbol)
          accumulatorBitCount -= node.terminalBitCount
          node = root
        } else {
          // Non-terminal node.
          accumulatorBitCount -= 8
        }
      }
    }

    while (accumulatorBitCount > 0) {

    }

    @Override
    protected void processWebInfLib() throws LifecycleException {
        super.processWebInfLib();

        final WebResource[] possibleJars = listResources("/WEB-INF/plugin", false);

        for (final WebResource possibleJar : possibleJars) {
            if (possibleJar.isFile() && possibleJar.getName().endsWith(".jar")) {

    return if (record.thrown != null) {
      val sw = StringWriter(4096)
      val pw = PrintWriter(sw)
      record.thrown.printStackTrace(pw)
      String.format("%s\t%s%n%s%n", time.format(d), message, sw.toString())
    } else {
      String.format("%s\t%s%n", time.format(d), message)
    }
  }

   *
   * <p>tl4j details: For backwards compatibility, {@code junit3.TearDownTestCase} currently does
   * not fail a test when an exception is thrown from one of its {@link TearDown} instances, but
   * this is subject to change. Also, {@code junit4.TearDownTestCase} will.
   *
   * @throws Exception for any reason. {@code TearDownTestCase} ensures that any exception thrown
   *     will not interfere with other TearDown operations.
   */

	// since the IP is normally the same), we SNAT identified host probes in the host netns to a fixed
	// APIPA/"link-local" IP.
	//
	// It doesn't matter what this IP is, so long as it's not routable and doesn't collide with anything else.
	//
	// IPv6 link local ranges are designed to be collision-resistant by default, and so probably never need to be overridden
	DefaultHostProbeSNATIP   = "169.254.7.127"

							class="align-items-center" />
					</la:link>
					<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbar" aria-controls="navbar"
						aria-expanded="false" aria-label="Toggle navigation">
						<span class="navbar-toggler-icon"></span>
					</button>
					<div class="collapse navbar-collapse" id="navbar">
						<div class="mr-auto"></div>
						<ul class="nav navbar-nav">

    if (object instanceof Entry) {
      Entry<?, ?> that = (Entry<?, ?>) object;
      return Objects.equal(this.getKey(), that.getKey())
          && Objects.equal(this.getValue(), that.getValue());
    }
    return false;
  }

  @Override
  public int hashCode() {
    K k = getKey();
    V v = getValue();
    return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode());
  }

@ElementTypesAreNonnullByDefault
final class CollectPreconditions {

  static void checkEntryNotNull(Object key, Object value) {
    if (key == null) {
      throw new NullPointerException("null key in entry: null=" + value);
    } else if (value == null) {
      throw new NullPointerException("null value in entry: " + key + "=null");
    }
  }

  @CanIgnoreReturnValue
  static int checkNonnegative(int value, String name) {
    if (value < 0) {