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/*
* Copyright (c) 2011, 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 A type T is more specific than a type S, written T << S, if one
* of the following conditions is met:
* • T is S.
* • T is ⊥
* • S is dynamic.
* • S is a direct supertype of T.
* • T is a type parameter and S is the upper bound of T.
* • T is a type parameter and S is Object.
* • T is of the form I<T1, ..., Tn > and S is of the form I <S1, ..., Sn>
* and Ti << Si 1 <= i <= n.
* • T and S are both function types, and T << S under the rules of section
* (Types/Function Types).
* • T is a function type and S is Function.
* • T << U and U << S.
* << is a partial order on types. T is a subtype of S, written T <: S, iff
* [⊥/Dynamic]T << S.
* . . .
* An interface type T may be assigned to a type S, written T <=> S, if either
* T <: S or S <: T.
* @description Checks that if type T is a subtype of S1 and S2 where
* S1 <: S<G1> and S2 <: S<G2> then T is a subtype of S<G1> as well as S<G2>
* and every other supertype of S.
* @author iefremov
*/
import "../../../Utils/expect.dart";
class S<Type> {}
class S1 extends S<int> {}
class S2 extends S<double> {}
class T implements S1, S2 {}
main() {
Expect.isTrue(new T() is S<int>);
Expect.isTrue(new T() is S<double>);
Expect.isTrue(new T() is S<num>);
Expect.isTrue(new T() is S<Object>);
Expect.isTrue(new T() is S);
}