First cut at new layout

1 files changed, 43 insertions, 0 deletions

diff --git a/src/ProtocolBuffers/Descriptors/DescriptorUtil.cs b/src/ProtocolBuffers/Descriptors/DescriptorUtil.cs
new file mode 100644
index 00000000..c945616d
--- /dev/null
+++ b/src/ProtocolBuffers/Descriptors/DescriptorUtil.cs
@@ -0,0 +1,43 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.
+// http://code.google.com/p/protobuf/
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+using System.Collections.Generic;
+using Google.ProtocolBuffers.Collections;
+
+namespace Google.ProtocolBuffers.Descriptors {
+  /// <summary>
+  /// Internal class containing utility methods when working with descriptors.
+  /// </summary>
+  internal static class DescriptorUtil {
+    /// <summary>
+    /// Equivalent to Func[TInput, int, TOutput] but usable in .NET 2.0. Only used to convert
+    /// arrays.
+    /// </summary>
+    internal delegate TOutput IndexedConverter<TInput, TOutput>(TInput element, int index);
+
+    /// <summary>
+    /// Converts the given array into a read-only list, applying the specified conversion to
+    /// each input element.
+    /// </summary>
+    internal static IList<TOutput> ConvertAndMakeReadOnly<TInput, TOutput>(IList<TInput> input,
+        IndexedConverter<TInput, TOutput> converter) {
+      TOutput[] array = new TOutput[input.Count];
+      for (int i = 0; i < array.Length; i++) {
+        array[i] = converter(input[i], i);
+      }
+      return Lists<TOutput>.AsReadOnly(array);
+    }
+  }
+}