Fasta builders.

pkg/fasta/lib/src/builder/modifier_builder.dart

Index: pkg/fasta/lib/src/builder/modifier_builder.dart
diff --git a/pkg/fasta/lib/src/builder/modifier_builder.dart b/pkg/fasta/lib/src/builder/modifier_builder.dart
new file mode 100644
index 0000000000000000000000000000000000000000..7dd8b2b2bb9b145931e6d8636951c4fd0bbaf999
--- /dev/null
+++ b/pkg/fasta/lib/src/builder/modifier_builder.dart
@@ -0,0 +1,29 @@
+// Copyright (c) 2016, 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.
+
+library fasta.modifier_builder;
+
+import '../modifier.dart' show
+    abstractMask,
+    constMask,
+    externalMask,
+    finalMask,
+    staticMask;
+
+import 'builder.dart' show
+    Builder;
+
+abstract class ModifierBuilder extends Builder {
+  int get modifiers;
+
+  bool get isAbstract => (modifiers & abstractMask) != 0;
+
+  bool get isConst => (modifiers & constMask) != 0;
+
+  bool get isExternal => (modifiers & externalMask) != 0;
+
+  bool get isFinal => (modifiers & finalMask) != 0;
+
+  bool get isStatic => (modifiers & staticMask) != 0;
+}