blob: 7c1dac0677f21a173be4bd0f7d38dce29c38606d [file] [log] [blame]
* 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
* typeParameter ::= metadata identifier (extends typeNotVoid)?
* typeParameters ::= ‘<’ typeParameter (‘,’ typeParameter)* ‘>’
* ...
* It is a compile-time error if a type parameter is a supertype of its upper
* bound when that upper bound is itself a type variable.
* This prevents circular declarations like [X extends X] and [X extends Y, Y
* extends X].
* @description Checks that it is a compile error if typedef type variable is a
* supertype of its upper bound.
* @author
typedef Alias1<X extends X> = void Function(X); //# 01: compile-time error
typedef Alias2<X extends Y, Y extends X> = void Function(X, Y); //# 02: compile-time error
typedef Alias3<X extends Y, Y extends Z, Z extends X> = void Function(X, Y, Z); //# 03: compile-time error
main() {}