// ErrIsFull is returned when the buffer is full and not blocking.
	ErrIsFull = errors.New("ringbuffer is full")

	// ErrIsEmpty is returned when the buffer is empty and not blocking.
	ErrIsEmpty = errors.New("ringbuffer is empty")

	// ErrIsNotEmpty is returned when the buffer is not empty and not blocking.
	ErrIsNotEmpty = errors.New("ringbuffer is not empty")

## ty

If ty is available, use it to check types.

## Asyncer

When needing to run blocking code inside of async functions, or async code inside of blocking functions, suggest using Asyncer.

Prefer it over AnyIO or asyncio.

Install:

```bash
uv add asyncer
```

Run blocking sync code inside of async with `asyncify()`:

```python
from asyncer import asyncify
from fastapi import FastAPI

        assertThrows(ExecutionException.class, () -> getDone(task));
    assertThat(executionException).hasCauseThat().isEqualTo(e);
  }

  @J2ktIncompatible
  @GwtIncompatible // blocking wait
  public void testCancel_interrupted() throws Exception {
    AtomicBoolean interruptedExceptionThrown = new AtomicBoolean();
    CountDownLatch enterLatch = new CountDownLatch(1);

{* ../../docs_src/stream_data/tutorial002_py310.py ln[30:34] hl[31] *}

/// tip

If you need to call blocking code from inside of an async function, or an async function from inside of a blocking function, you could use [Asyncer](https://asyncer.tiangolo.com), a sibling library to FastAPI.

///

        assertThrows(ExecutionException.class, () -> getDone(task));
    assertThat(executionException).hasCauseThat().isEqualTo(e);
  }

  @J2ktIncompatible
  @GwtIncompatible // blocking wait
  public void testCancel_interrupted() throws Exception {
    AtomicBoolean interruptedExceptionThrown = new AtomicBoolean();
    CountDownLatch enterLatch = new CountDownLatch(1);

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3

import okio.IOException

/**
 * Returns the trailers that follow an HTTP response, blocking if they aren't ready yet.
 * Implementations of this interface should respond to [Call.cancel] by immediately throwing an
 * [IOException].
 *

   * Drains the queue as {@link BlockingQueue#drainTo(Collection, int)}, but if the requested {@code
   * numElements} elements are not available, it will wait for them up to the specified timeout.
   *
   * @param q the blocking queue to be drained
   * @param buffer where to add the transferred elements
   * @param numElements the number of elements to be waited for
   * @param timeout how long to wait before giving up

)

_T = TypeVar("_T")


@asynccontextmanager
async def contextmanager_in_threadpool(
    cm: AbstractContextManager[_T],
) -> AsyncGenerator[_T, None]:
    # blocking __exit__ from running waiting on a free thread
    # can create race conditions/deadlocks if the context manager itself
    # has its own internal pool (e.g. a database connection pool)

      Future<V> future) {
    if (future instanceof ListenableFuture) {
      return (ListenableFuture<V>) future;
    }
    return new ListenableFutureAdapter<>(future);
  }

  /**
   * Submits a blocking task for the given {@link Future} to provide {@link ListenableFuture}
   * functionality.
   *
   * <p><b>Warning:</b> If the input future does not already implement {@code ListenableFuture}, the

# Use plain def when calling blocking/sync code or when in doubt
@app.get("/items/")
def read_items():
    data = some_blocking_library.fetch_items()
    return data
```

In case of doubt, or by default, use regular `def` functions, those will be run in a threadpool so they don't block the event loop.

The same rules apply to dependencies.