Preliminary checked mirrors (not ready for review yet)

pkg/checked_mirrors/lib/src/utils.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.
+
+/// Holds some common functions that manipulate mirror objects.
+library checked_mirrors.src.utils;
+
+import 'dart:mirrors';
+
+/// Helper to retrieve the library uri where [object] is defined.
+Uri getLibraryUriOf(Mirror object) {
+  var declaration = getDeclarationOf(object);
+  if (declaration == null) return null;
+  if (declaration is LibraryMirror) return declaration.uri;
+  return getLibraryUriOf(declaration.owner);
+}
+
+/// Helper to retrieve the declaration of [object].
+DeclarationMirror getDeclarationOf(Mirror object) {
+  if (object is DeclarationMirror) return object;
+  if (object is InstanceMirror) return object.type;
+  return null;
+}