TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

      assertBitEquals(prev, at.get());
      assertTrue(at.compareAndSet(prev, x));
      assertBitEquals(x, at.get());
      prev = x;
    }
  }

  /** compareAndSet in one thread enables another waiting for value to succeed */
  public void testCompareAndSetInMultipleThreads() throws Exception {
    AtomicDouble at = new AtomicDouble(1.0);
    Thread t =
        newStartedThread(
            new CheckedRunnable() {

FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

/// info

Added in FastAPI 0.134.0.

///

## What is a Stream? { #what-is-a-stream }

"**Streaming**" data means that your app will start sending data items to the client without waiting for the entire sequence of items to be ready.

So, it will send the first item, the client will receive and start processing it, and you might still be producing the next item.

```mermaid
sequenceDiagram

      <a class="announce-link" href="https://fastapicloud.com" target="_blank">
        <span class="twemoji">
          {% include ".icons/material/cloud-arrow-up.svg" %}
        </span> Join the <strong>FastAPI Cloud</strong> waiting list 🚀
      </a>
    </div>
    <div class="item">
      <a class="announce-link" href="https://x.com/fastapi" target="_blank">
        <span class="twemoji">

     <span style="background-color:#007166"><font color="#D3D7CF"> INFO </font></span>  Waiting for application startup.
     <span style="background-color:#007166"><font color="#D3D7CF"> INFO </font></span>  Application startup complete.
```

</div>

They have different levels of permissions and [specific instructions](./management-tasks.md).

Some of the tasks they can perform include:

* Adding labels to PRs.
* Editing PR titles.
* Adding commits on top of PRs to tweak them.
* Mark answers in GitHub Discussions questions, etc.
* Merge some specific types of PRs.

There will be a label for each language using the language code, like `lang-{lang code}`, for example, `lang-es` for Spanish, `lang-fr` for French, etc.

* Add the specific language label.
* Add the label `awaiting-review`.

				}
			}

			if task.respCh != nil {
				task.respCh <- healResult{result: res, err: err}
				continue
			}

			// when respCh is not set caller is not waiting but we
			// update the relevant metrics for them
			if bgSeq != nil {
				if err == nil {
					bgSeq.countHealed(res.Type)
				} else {
					bgSeq.countFailed(res.Type)
				}
			}