private PunctuationSyntax XmlMakeBeginProcessingInstructionToken(SyntaxList<SyntaxNode> precedingTrivia, Func<SyntaxList<SyntaxNode>> scanTrailingTrivia) { Debug.Assert(PeekChar() == '<'); Debug.Assert(PeekAheadChar(1) == '?'); AdvanceChar(2); var followingTrivia = scanTrailingTrivia(); return MakePunctuationToken(SyntaxKind.LessThanQuestionToken, "<?", precedingTrivia, followingTrivia); }