import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/**
 * An iterator that transforms a backing iterator; for internal use. This avoids the object overhead
 * of constructing a {@link com.google.common.base.Function Function} for internal methods.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
abstract class TransformedIterator<F extends @Nullable Object, T extends @Nullable Object>
    implements Iterator<T> {

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

package com.google.common.collect;

import com.google.common.base.Function;
import com.google.common.testing.ForwardingWrapperTester;
import java.util.Deque;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@code ForwardingDeque}.
 *

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

package com.google.common.collect;

import com.google.common.base.Function;
import com.google.common.testing.ForwardingWrapperTester;
import java.util.ListIterator;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**

import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/**
 * An iterator that transforms a backing iterator; for internal use. This avoids the object overhead
 * of constructing a {@link com.google.common.base.Function Function} for internal methods.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
abstract class TransformedIterator<F extends @Nullable Object, T extends @Nullable Object>
    implements Iterator<T> {

8. Notice that this *path operation function* uses regular `def` instead of `async def`.

    As always, in FastAPI you can combine `def` and `async def` as needed.

    If you need a refresher about when to use which, check out the section _"In a hurry?"_ in the docs about [`async` and `await`](../async.md#in-a-hurry).

# `Request` class

You can declare a parameter in a *path operation function* or dependency to be of type `Request` and then you can access the raw request object directly, without any validation, etc.

Read more about it in the [FastAPI docs about using Request directly](https://fastapi.tiangolo.com/advanced/using-request-directly/)

You can import it directly from `fastapi`:

```python
from fastapi import Request
```

/// tip

	ctxField
	ctxParam
	ctxAssign2 // assignment of a single expression to two variables
	ctxSwitch
	ctxTypeSwitch
	ctxFile
	ctxDecl
	ctxSpec
	ctxDefer
	ctxCall  // any function call other than ctxCall2
	ctxCall2 // function call whose result is assigned to two variables
	ctxSelector
)

// walk walks the AST x, calling visit(f, x, context) for each node.

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

package com.google.common.collect;

import com.google.common.base.Function;
import com.google.common.testing.EqualsTester;
import com.google.common.testing.ForwardingWrapperTester;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**

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

package com.google.common.collect;

import com.google.common.base.Function;
import com.google.common.testing.EqualsTester;
import com.google.common.testing.ForwardingWrapperTester;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**

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

package com.google.common.collect;

import com.google.common.base.Function;
import com.google.common.testing.EqualsTester;
import com.google.common.testing.ForwardingWrapperTester;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**