func (s *Singleton[T]) IsSet() bool {
	select {
	case <-s.set:
		return true
	default:
		return false
	}
}

// Set the value and unblock all Get requests.
// This may only be called once, a second call will panic.
func (s *Singleton[T]) Set(v *T) {
	s.v = v
	close(s.set)

                "flags should be DCERPC_FIRST_FRAG | DCERPC_LAST_FRAG");
        // Verify that the super constructor was called with the correct handle.
        // This is implicitly tested by the object being created without error and
        // the fields set by the constructor being correct.
    }

          finishLine(true);
          start = pos + 1;
          break;

        default:
          // do nothing
      }
    }
    line.append(cbuf, start, off + len - start);
  }

  /** Called when a line is complete. */
  @CanIgnoreReturnValue
  private boolean finishLine(boolean sawNewline) throws IOException {
    String separator = sawReturn ? (sawNewline ? "\r\n" : "\r") : (sawNewline ? "\n" : "");

   *   <li>{@link Cancellation} terminal state, {@code cancel} was called.
   *   <li>{@link Failure} terminal state, {@code setException} was called.
   *   <li>{@link DelegatingToFuture} intermediate state, {@code setFuture} was called.
   *   <li>{@link #NULL} terminal state, {@code set(null)} was called.
   *   <li>Any other non-null value, terminal state, {@code set} was called with a non-null
   *       argument.
   * </ul>
   */

So, in a URL like:

```
https://example.com/items/foo
```

...the path would be:

```
/items/foo
```

/// info

A "path" is also commonly called an "endpoint" or a "route".

///

While building an API, the "path" is the main way to separate "concerns" and "resources".

#### Operation { #operation }

        assertEquals(expectedFlags, msrpcSamrOpenDomain.getFlags(), "flags should be initialized to DCERPC_FIRST_FRAG | DCERPC_LAST_FRAG");

        // Since SamrOpenDomain's constructor is called, we implicitly test that the arguments
        // are passed up. Mockito cannot directly verify super() calls without PowerMock,
        // which is not ideal for simple constructor tests.

    return [{"item_id": "Foo"}]


def use_route_names_as_operation_ids(app: FastAPI) -> None:
    """
    Simplify operation IDs so that generated API clients have simpler function
    names.

    Should be called only after all routes have been added.
    """
    for route in app.routes:
        if isinstance(route, APIRoute):
            route.operation_id = route.name  # in this case, 'read_items'

If we want to call asynchronous functions in our tests, our test functions have to be asynchronous. AnyIO provides a neat plugin for this, that allows us to specify that some test functions are to be called asynchronously.

## HTTPX { #httpx }

Even if your **FastAPI** application uses normal `def` functions instead of `async def`, it is still an `async` application underneath.

   * {@code next}. Once the implementation either invokes {@code endOfData} or throws an exception,
   * {@code computeNext} is guaranteed to never be called again.
   *
   * <p>If this method throws an exception, it will propagate outward to the {@code hasNext} or
   * {@code next} invocation that invoked this method. Any further attempts to use the iterator will

   * and then applying {@code function} to that value. Note that the resulting supplier will not
   * call {@code supplier} or invoke {@code function} until it is called.
   */
  public static <F extends @Nullable Object, T extends @Nullable Object> Supplier<T> compose(
      Function<? super F, T> function, Supplier<F> supplier) {
    return new SupplierComposition<>(function, supplier);
  }