ILSpy/ICSharpCode.Decompiler/CSharp/Syntax/PatternMatching/Match.cs

// Copyright (c) 2011-2013 AlphaSierraPapa for the SharpDevelop Team
// 
// 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
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// 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
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// DEALINGS IN THE SOFTWARE.

#nullable enable

using System.Collections.Generic;

namespace ICSharpCode.Decompiler.CSharp.Syntax.PatternMatching
{
	/// <summary>
	/// Represents the result of a pattern matching operation.
	/// </summary>
	public struct Match
	{
		// TODO: maybe we should add an implicit Match->bool conversion? (implicit operator bool(Match m) { return m != null; })

		List<KeyValuePair<string, INode?>> results;

		public bool Success {
			get { return results != null; }
		}

		internal static Match CreateNew()
		{
			Match m;
			m.results = new List<KeyValuePair<string, INode?>>();
			return m;
		}

		internal int CheckPoint()
		{
			return results.Count;
		}

		internal void RestoreCheckPoint(int checkPoint)
		{
			results.RemoveRange(checkPoint, results.Count - checkPoint);
		}

		public IEnumerable<INode?> Get(string groupName)
		{
			if (results == null)
				yield break;
			foreach (var pair in results)
			{
				if (pair.Key == groupName)
					yield return pair.Value;
			}
		}

		public IEnumerable<T> Get<T>(string groupName) where T : INode
		{
			if (results == null)
				yield break;
			foreach (var pair in results)
			{
				if (pair.Key == groupName)
					yield return (T)pair.Value!;
			}
		}

		public bool Has(string groupName)
		{
			if (results == null)
				return false;
			foreach (var pair in results)
			{
				if (pair.Key == groupName)
					return true;
			}
			return false;
		}

		public void Add(string? groupName, INode? node)
		{
			if (groupName != null && node != null)
			{
				results.Add(new KeyValuePair<string, INode?>(groupName, node));
			}
		}

		internal void AddNull(string? groupName)
		{
			if (groupName != null)
			{
				results.Add(new KeyValuePair<string, INode?>(groupName, null));
			}
		}
	}
}