Add TypeMirror.isSubtypeOf, TypeMirror.isAssignableTo, ClassMirror.isSubclassOf

sdk/lib/mirrors/mirrors.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.
 
 // For the purposes of the mirrors library, we adopt a naming
 // convention with respect to getters and setters.  Specifically, for
 // some variable or field...
 //
 //   var myField;
 //
@@ skipping 656 matching lines @@
   /**
    * A mirror on the original declaration of this type.
    *
    * For most classes, they are their own original declaration.  For
    * generic classes, however, there is a distinction between the
    * original class declaration, which has unbound type variables, and
    * the instantiations of generic classes, which have bound type
    * variables.
    */
   TypeMirror get originalDeclaration;
+
+
+  /**
+   * Checks the subtype relationship, denoted by [:<::] in the language
+   * specification. This is the type relationship used in [:is:] test checks.
+   */
+  bool isSubtypeOf(TypeMirror other);
+
+  /**
+   * Checks the assignability relationship, denoted by [:<=>:] in the language
+   * specification. This is the type relationship tested on assignment in
+   * checked mode.
+   */
+  bool isAssignableTo(TypeMirror other);
 }
 
 /**
  * A [ClassMirror] reflects a Dart language class.
  */
 abstract class ClassMirror implements TypeMirror, ObjectMirror {
   /**
    * Returns true if this mirror reflects a non-generic class or an instantiated
    * generic class in the current isolate. Otherwise, returns false.
    */
@@ skipping 135 matching lines @@
    *
    *     (r1, ..., rn, [p1 = d1, ..., pk = dk]) {
    *       return this.invoke(name, [r1, ..., rn, p1, ..., pk]);
    *     }
    *
    * if m has required parameters r1, ..., rn, and optional positional
    * parameters p1, ..., pk with defaults d1, ..., dk.  Otherwise, an
    * [ArgumentError] is thrown.
    */
   Function operator [](Symbol name);
+
+  /**
+   * Returns whether the class denoted by the receiver is a subclass of the
+   * class denoted by the argument.
+   *
+   * Note that the subclass relationship is reflexive.
+   */
+  bool isSubclassOf(ClassMirror other);
 }
 
 /**
  * A [FunctionTypeMirror] represents the type of a function in the
  * Dart language.
  */
 abstract class FunctionTypeMirror implements ClassMirror {
   /**
    * Returns the return type of the reflectee.
    */
@@ skipping 366 matching lines @@
    *
    * When used as metadata on an import of "dart:mirrors", this metadata does
    * not apply to the library in which the annotation is used, but instead
    * applies to the other libraries (all libraries if "*" is used).
    */
   final override;
 
   const MirrorsUsed(
       {this.symbols, this.targets, this.metaTargets, this.override});
 }