// Copyright (c) 2016 Daniel Grunwald // // Permission is hereby granted, free of charge, to any person obtaining a copy of this // software and associated documentation files (the "Software"), to deal in the Software // without restriction, including without limitation the rights to use, copy, modify, merge, // publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons // to whom the Software is furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in all copies or // substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, // INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR // PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE // FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER // DEALINGS IN THE SOFTWARE. using System.Collections.Generic; namespace ICSharpCode.Decompiler.IL.Patterns { public class CaptureGroup {} /// <summary> /// Data holder for the overall pattern matching operation. /// </summary> /// <remarks> /// This type is a struct in order to prevent unnecessary memory allocations during pattern matching. /// The default value <c>default(Match)</c> represents an unsuccessful match. /// </remarks> public struct Match { static readonly List<KeyValuePair<CaptureGroup, ILInstruction>> emptyResults = new List<KeyValuePair<CaptureGroup, ILInstruction>>(); List<KeyValuePair<CaptureGroup, ILInstruction>> results; /// <summary> /// Gets whether the match was successful. /// </summary> public bool Success { get { return results != null; } internal set { if (value) { if (results == null) results = emptyResults; } else { results = null; } } } /// <summary> /// Gets whether the match was successful. /// </summary> public static bool operator true(Match m) { return m.Success; } /// <summary> /// Gets whether the match failed. /// </summary> public static bool operator false(Match m) { return !m.Success; } internal void Add(CaptureGroup g, ILInstruction n) { if (results == null) results = new List<KeyValuePair<CaptureGroup, ILInstruction>>(); results.Add(new KeyValuePair<CaptureGroup, ILInstruction>(g, n)); } internal int CheckPoint() { return results != null ? results.Count : 0; } internal void RestoreCheckPoint(int checkPoint) { if (results != null) results.RemoveRange(checkPoint, results.Count - checkPoint); } public IEnumerable<ILInstruction> Get(CaptureGroup captureGroup) { if (results != null) { foreach (var pair in results) { if (pair.Key == captureGroup) yield return pair.Value; } } } } }