Support runtime check of function types.

tests/language/function_subtype_named1_test.dart

+// Copyright (c) 2013, 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.
+// Dart test program for constructors and initializers.
+
+// Check function subtyping.
+
+import 'package:expect/expect.dart';
+
+void void_() {}
+void void__int(int i) {}
+void void___a_int({int a}) {}
+void void___a_int2({int a}) {}
+void void___b_int({int b}) {}
+void void___a_Object({Object a}) {}
+void void__int__a_int(int i1, {int a}) {}
+void void__int__a_int2(int i1, {int a}) {}
+void void___a_double({double a}) {}
+void void___a_int_b_int({int a, int b}) {}
+void void___a_int_b_int_c_int({int a, int b, int c}) {}
+void void___a_int_c_int({int a, int c}) {}
+void void___b_int_c_int({int b, int c}) {}
+void void___c_int({int c}) {}
+
+typedef void t_void_();
+typedef void t_void__int(int i);
+typedef void t_void___a_int({int a});
+typedef void t_void___a_int2({int a});
+typedef void t_void___b_int({int b});
+typedef void t_void___a_Object({Object a});
+typedef void t_void__int__a_int(int i1, {int a});
+typedef void t_void__int__a_int2(int i1, {int a});
+typedef void t_void___a_double({double a});
+typedef void t_void___a_int_b_int({int a, int b});
+typedef void t_void___a_int_b_int_c_int({int a, int b, int c});
+typedef void t_void___a_int_c_int({int a, int c});
+typedef void t_void___b_int_c_int({int b, int c});
+typedef void t_void___c_int({int c});
+
+main() {
+  // Test ({int a})->void <: ()->void.
+  Expect.isTrue(void___a_int is t_void_);
+  // Test ({int a})->void <: (int)->void.
+  Expect.isFalse(void___a_int is t_void__int);
+  // Test (int)->void <: ({int a})->void.
+  Expect.isFalse(void__int is t_void___a_int);
+  // Test ({int a})->void <: ({int a})->void.
+  Expect.isTrue(void___a_int is t_void___a_int2);
+  // Test ({int a})->void <: ({int b})->void.
+  Expect.isFalse(void___a_int is t_void___b_int);
+  // Test ({Object a})->void <: ({int a})->void.
+  Expect.isTrue(void___a_Object is t_void___a_int);
+  // Test ({int a})->void <: ({Object a})->void.
+  Expect.isTrue(void___a_int is t_void___a_Object);
+  // Test (int,{int a})->void <: (int,{int a})->void.
+  Expect.isTrue(void__int__a_int is t_void__int__a_int2);
+  // Test ({int a})->void <: ({double a})->void.
+  Expect.isFalse(void___a_int is t_void___a_double);
+  // Test ({int a})->void <: ({int a,int b})->void.
+  Expect.isFalse(void___a_int is t_void___a_int_b_int);
+  // Test ({int a,int b})->void <: ({int a})->void.
+  Expect.isTrue(void___a_int_b_int is t_void___a_int);
+  // Test ({int a,int b,int c})->void <: ({int a,int c})->void.
+  Expect.isTrue(void___a_int_b_int_c_int is t_void___a_int_c_int);
+  // Test ({int a,int b,int c})->void <: ({int b,int c})->void.
+  Expect.isTrue(void___a_int_b_int_c_int is t_void___b_int_c_int);
+  // Test ({int a,int b,int c})->void <: ({int c})->void.
+  Expect.isTrue(void___a_int_b_int_c_int is t_void___c_int);
+}