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pkg/dev_compiler/tool/input_sdk/lib/isolate/capability.dart

-// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-part of dart.isolate;
-
-/**
- * An unforgeable object that comes back as equal when passed through other
- * isolates.
- *
- * Sending a capability object to another isolate, and getting it back,
- * will produce an object that is equal to the original.
- * There is no other way to create objects equal to a capability object.
- *
- * Capabilities can be used as access guards: A remote isolate can send
- * a request for an operation, but it is only allowed if the request contains
- * the correct capability object.
- *
- * This allows exposing the same interface to multiple clients,
- * but restricting some operations to only those clients
- * that have also been given the corresponding capability.
- *
- * Capabilities can be used inside a single isolate,
- * but they have no advantage over
- * just using `new Object` to create a unique object,
- * and it offers no real security against other code
- * running in the same isolate.
- */
-class Capability {
-  /**
-   * Create a new unforgeable capability object.
-   */
-  external factory Capability();
-}