Value<? extends Map<K, V>> result = DefaultMapProperty.this.calculateOwnValue(consumer);
            if (result.isMissing()) {
                return result.asType();
            }
            Value<? extends V> resultValue = Value.ofNullable(result.getWithoutSideEffect().get(key));
            return resultValue.withSideEffect(SideEffect.fixedFrom(result));
        }
    }

    @Override
    public FileTree visit(Closure closure) {
        return visit(fileVisitorFrom(closure));
    }

    static FileVisitor fileVisitorFrom(Closure closure) {
        return DefaultGroovyMethods.asType(closure, FileVisitor.class);
    }

    @Override
    public FileTree visit(final Action<? super FileVisitDetails> visitor) {
        return visit(new FileVisitor() {
            @Override

        for (Provider<R> provider : items) {
            Value<? extends R> value = Providers.internal(provider).calculateValue(consumer);
            if (value.isMissing()) {
                return value.asType();
            }
            values.add(value);
        }

        ImmutableList.Builder<R> result = ImmutableList.builderWithExpectedSize(values.size());
        for (Value<? extends R> value : values) {

        }
    }

    @Nonnull
    protected Value<OUT> mapValue(EvaluationContext.ScopeContext context, Value<? extends IN> value) {
        if (value.isMissing()) {
            return value.asType();
        }
        return value.transform(transformer);
    }

    protected void beforeRead(EvaluationContext.ScopeContext context) {
        provider.getProducer().visitContentProducerTasks(producer -> {

        1 * source2.visit(visitor)
    }

    def visitsEachTreeWithClosure() {
        final Closure visitor = TestUtil.TEST_CLOSURE
        final FileVisitor closureAsVisitor = DefaultGroovyMethods.asType(visitor, FileVisitor.class)

        when:
        tree.visit(visitor)

        then:
        1 * source1.visit(closureAsVisitor)
        1 * source2.visit(closureAsVisitor)
    }

            Value<? extends T> value = provider.calculateValue(consumer);
            if (value.isMissing()) {
                return value.asType();
            }

            collector.add(value.getWithoutSideEffect(), collection);
            return Value.present().withSideEffect(SideEffect.fixedFrom(value));
        }

        @Override

 * }
 *
 * task generateRestApiDocs(type: Javadoc) {
 *   source = sourceSets.main.allJava
 *   destinationDir = reporting.file("rest-api-docs")
 *   options.docletpath = configurations.jaxDoclet.files.asType(List)
 *   options.doclet = "com.lunatech.doclets.jax.jaxrs.JAXRSDoclet"
 *   options.addStringOption("jaxrscontext", "http://localhost:8080/myapp")
 * }
 * </pre>
 */
@CacheableTask

        private final Value<? extends C> value;

        public NoValueSupplier(Value<? extends C> value) {
            assert value.isMissing();
            this.value = value.asType();
        }

        @Override
        public CollectionSupplier<T, C> absentIgnoring() {
            return Cast.uncheckedCast(emptySupplier());
        }

        @Override

         * CRC32C to Checksum. This may carry some performance cost
         * (https://stackoverflow.com/a/22321671/28465), but I'd have to benchmark more carefully to
         * even detect it.
         */
        return MethodHandles.lookup()
            .findConstructor(clazz, methodType(void.class))
            .asType(methodType(Checksum.class));

Working with files::
 * You can no longer cast `FileCollection` objects to other types using the `as` keyword or the `asType()` method.
 * You can no longer pass `null` as the configuration action of link:{javadocPath}/org/gradle/api/file/CopySpec.html#from-java.lang.Object-org.gradle.api.Action-[CopySpec.from(Object, Action)].