source: trunk/HeuristicLab.ExtLibs/HeuristicLab.NRefactory/5.5.0/NRefactory-5.5.0/PatternMatching/Backreference.cs @ 16824

// 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
// 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;
using System.Linq;

namespace ICSharpCode.NRefactory.PatternMatching
{
  /// <summary>
  /// Matches the last entry in the specified named group.
  /// </summary>
  public class Backreference : Pattern
  {
    readonly string referencedGroupName;
    
    public string ReferencedGroupName {
      get { return referencedGroupName; }
    }
    
    public Backreference(string referencedGroupName)
    {
      if (referencedGroupName == null)
        throw new ArgumentNullException("referencedGroupName");
      this.referencedGroupName = referencedGroupName;
    }
    
    public override bool DoMatch(INode other, Match match)
    {
      var last = match.Get (referencedGroupName).Last ();
      if (last == null && other == null)
        return true;
      return last.IsMatch(other);
    }
  }
}