ICSharpCode.NRefactory.CSharp.CombineQueryExpressions.TryRemoveTransparentIdentifier C# (CSharp) Method

		bool TryRemoveTransparentIdentifier(QueryExpression query, QueryFromClause fromClause, QueryExpression innerQuery, string continuationIdentifier, out string transparentIdentifier)
		{
			transparentIdentifier = fromClause.Identifier;

			Match match = selectTransparentIdentifierPattern.Match(innerQuery.Clauses.Last());
			if (!match.Success)
				return false;
			QuerySelectClause selectClause = (QuerySelectClause)innerQuery.Clauses.Last();
			Expression nae1 = match.Get<Expression>("nae1").SingleOrDefault();
			string nae1Name = ExtractExpressionName(ref nae1);
			if (nae1Name == null)
				return false;

			Expression nae2 = match.Get<Expression>("nae2").SingleOrDefault();
			string nae2Name = ExtractExpressionName(ref nae2);
			if (nae1Name == null)
				return false;

			bool introduceLetClause = true;
			var nae1Identifier = nae1 as IdentifierExpression;
			var nae2Identifier = nae2 as IdentifierExpression;
			if (nae1Identifier != null && nae2Identifier != null && nae1Identifier.Identifier == nae1Name && nae2Identifier.Identifier == nae2Name) {
				introduceLetClause = false;
			}

			if (nae1Name != continuationIdentifier) {
				if (nae2Name == continuationIdentifier) {
					//Members are in reversed order
					string tempName = nae1Name;
					Expression tempNae = nae1;

					nae1Name = nae2Name;
					nae1 = nae2;
					nae2Name = tempName;
					nae2 = tempNae;
				} else {
					return false;
				}
			}

			if (introduceLetClause && innerQuery.Clauses.OfType<QueryFromClause>().Any(from => from.Identifier == nae2Name)) {
				return false;
			}
			if (introduceLetClause && innerQuery.Clauses.OfType<QueryJoinClause>().Any(join => join.JoinIdentifier == nae2Name)) {
				return false;
			}

			// from * in (from x in ... select new { x = x, y = expr }) ...
			// =>
			// from x in ... let y = expr ...
			fromClause.Remove();
			selectClause.Remove();
			// Move clauses from innerQuery to query
			QueryClause insertionPos = null;
			foreach (var clause in innerQuery.Clauses) {
				query.Clauses.InsertAfter(insertionPos, insertionPos = clause.Detach());
			}
			if (introduceLetClause) {
				query.Clauses.InsertAfter(insertionPos, new QueryLetClause { Identifier = nae2Name, Expression = nae2.Detach() });
			}
			return true;
		}