1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
#region Copyright notice and license
// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#endregion
using System.Collections.Generic;
using System.Collections.ObjectModel;
namespace Google.Protobuf.Reflection
{
/// <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 new ReadOnlyCollection<TOutput>(array);
}
}
}