import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Set;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * An immutable sorted set with one or more elements. TODO(jlevy): Consider separate class for a
 * single-element sorted set.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 */

```Python hl_lines="16"
{!../../../docs_src/dependencies/tutorial011.py!}
```

这样就可以**参数化**依赖项，它包含 `checker.fixed_content` 的属性 - `"bar"`。

## 把实例作为依赖项

然后，不要再在 `Depends(checker)` 中使用 `Depends(FixedContentQueryChecker)`， 而是要使用 `checker`，因为依赖项是类实例 - `checker`，不是类。

处理依赖项时，**FastAPI** 以如下方式调用 `checker`：

```Python
checker(q="somequery")
```

……并用*路径操作函数*的参数 `fixed_content_included` 返回依赖项的值：

```Python hl_lines="20"

          <item index="10" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NullableDecl" />
          <item index="11" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NullableType" />
          <item index="12" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.qual.Nullable" />

                }
            }
            configurations.conf.resolutionStrategy {
                force 'org:foo:1.0'
            }
        """

        when:
        run 'checkDeps'

        then:
        resolve.expectGraph {
            root(":", ":test:") {
                constraint("org:foo:1.1","org:foo:1.0")
                module("org:bar:1.0") {

	if err := DB.Create(&pet).Error; err != nil {
		t.Fatalf("errors happened when create: %v", err)
	}

	CheckPet(t, pet, pet)

	// Find
	var pet2 Pet
	DB.Find(&pet2, "id = ?", pet.ID)
	DB.Model(&pet2).Association("Toy").Find(&pet2.Toy)
	CheckPet(t, pet2, pet)

	// Count
	AssertAssociationCount(t, pet, "Toy", 1, "")

	// Append
	toy := Toy{Name: "toy-has-one-append"}

// - service.istio.io/canonical-revision
//
// If the labels are not in the map, a set of fallbacks are checked. For canonical name,
// `app.kubernetes.io/name` is checked, then `app`, evenutually falling back to the
// supplied `workloadName`. For canonical revision, `app.kubernetes.io/version` is checked,
// followed by `version` and finally defaulting to the literal value of `"latest"`.

## Die Instanz als Abhängigkeit verwenden

Dann könnten wir diesen `checker` in einem `Depends(checker)` anstelle von `Depends(FixedContentQueryChecker)` verwenden, da die Abhängigkeit die Instanz `checker` und nicht die Klasse selbst ist.

Und beim Auflösen der Abhängigkeit ruft **FastAPI** diesen `checker` wie folgt auf:

```Python
checker(q="somequery")

// may be set to the cause for the failure.
// The check parameter may be nil if convertibleTo is invoked through an
// exported API call, i.e., when all methods have been type-checked.
func (x *operand) convertibleTo(check *Checker, T Type, cause *string) bool {
	// "x is assignable to T"
	if ok, _ := x.assignableTo(check, T, cause); ok {
		return true
	}

	origT := T
	V := Unalias(x.typ)
	T = Unalias(T)

 * ExecutionException} when the exception thrown by a task is an unchecked exception. However, it
 * may also wrap a checked exception in some cases.
 *
 * <p>When wrapping an {@code Error} from another thread, prefer {@link ExecutionError}. When
 * wrapping a checked exception, prefer {@code ExecutionException}.
 *
 * @author Charles Fry
 * @since 10.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault

import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
import java.util.logging.Level;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A helper which does some thread-safe operations for aggregate futures, which must be implemented
 * differently in GWT. Namely:
 *
 * <ul>