private VirtualTreePoint GetStartPoint(SourceText text, BaseTypeDeclarationSyntax node, EnvDTE.vsCMPart part)
            {
                int startPosition;

                switch (part)
                {
                    case EnvDTE.vsCMPart.vsCMPartName:
                    case EnvDTE.vsCMPart.vsCMPartAttributes:
                    case EnvDTE.vsCMPart.vsCMPartWhole:
                    case EnvDTE.vsCMPart.vsCMPartBodyWithDelimiter:
                    case EnvDTE.vsCMPart.vsCMPartHeaderWithAttributes:
                        throw Exceptions.ThrowENotImpl();

                    case EnvDTE.vsCMPart.vsCMPartHeader:
                        startPosition = node.GetFirstTokenAfterAttributes().SpanStart;
                        break;

                    case EnvDTE.vsCMPart.vsCMPartAttributesWithDelimiter:
                        if (node.AttributeLists.Count == 0)
                        {
                            throw Exceptions.ThrowEFail();
                        }

                        goto case EnvDTE.vsCMPart.vsCMPartWholeWithAttributes;

                    case EnvDTE.vsCMPart.vsCMPartWholeWithAttributes:
                        startPosition = node.GetFirstToken().SpanStart;
                        break;

                    case EnvDTE.vsCMPart.vsCMPartNavigate:
                        startPosition = node.Identifier.SpanStart;
                        break;

                    case EnvDTE.vsCMPart.vsCMPartBody:
                        if (node.OpenBraceToken.IsMissing || node.CloseBraceToken.IsMissing)
                        {
                            throw Exceptions.ThrowEFail();
                        }

                        return GetBodyStartPoint(text, node.OpenBraceToken);

                    default:
                        throw Exceptions.ThrowEInvalidArg();
                }

                return new VirtualTreePoint(node.SyntaxTree, text, startPosition);
            }
 private SyntaxToken GetFirstTokenAfterAttributes(BaseTypeDeclarationSyntax node)
 {
     return node.AttributeLists.Count != 0
         ? node.AttributeLists.Last().GetLastToken().GetNextToken()
         : node.GetFirstToken();
 }