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// Copyright (c) 2019, 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.
/// @assertion We say that a type T0 is a subtype of a type T1 (written T0 <: T1)
/// when:
/// Right Object: if T1 is Object then:
/// - if T0 is an unpromoted type variable with bound B then T0 <: T1 iff
/// B <: Object
/// - if T0 is a promoted type variable X & S then T0 <: T1 iff S <: Object
/// - if T0 is FutureOr<S> for some S, then T0 <: T1 iff S <: Object.
/// - if T0 is S* for any S, then T0 <: T1 iff S <: T1
/// - if T0 is Null, dynamic, void, or S? for any S, then the subtyping does not
/// hold (per above, the result of the subtyping query is false).
/// - Otherwise T0 <: T1 is true.
/// @description Check that if T0 is FutureOr<S> for some S and S <: Object then
/// T0 is subtype of T1
/// @author
import "dart:async";
class S {}
FutureOr<S> t0Instance = new Future.value(new S());
Object t1Instance = new Object();
const t1Default = const Object();
//# @T0 = FutureOr<S>
//# @T1 = Object