// <file>
// <copyright see="prj:///doc/copyright.txt"/>
// <license see="prj:///doc/license.txt"/>
// <owner name="Andrea Paatz" email="andrea@icsharpcode.net"/>
// <version>$Revision: 3263 $</version>
// </file>
using System;
using System.Globalization;
using System.IO;
using System.Text;
namespace ICSharpCode.NRefactory.Parser.VB
{
internal sealed class Lexer : AbstractLexer
{
bool lineEnd = true;
public Lexer(TextReader reader) : base(reader)
{
}
public override Token NextToken()
{
if (curToken == null) { // first call of NextToken()
curToken = Next();
specialTracker.InformToken(curToken.kind);
//Console.WriteLine("Tok:" + Tokens.GetTokenString(curToken.kind) + " --- " + curToken.val);
return curToken;
}
lastToken = curToken;
if (curToken.next == null) {
curToken.next = Next();
specialTracker.InformToken(curToken.next.kind);
}
curToken = curToken.next;
if (curToken.kind == Tokens.EOF && !(lastToken.kind == Tokens.EOL)) { // be sure that before EOF there is an EOL token
curToken = new Token(Tokens.EOL, curToken.col, curToken.line, "\n");
specialTracker.InformToken(curToken.kind);
curToken.next = new Token(Tokens.EOF, curToken.col, curToken.line, "\n");
specialTracker.InformToken(curToken.next.kind);
}
//Console.WriteLine("Tok:" + Tokens.GetTokenString(curToken.kind) + " --- " + curToken.val);
return curToken;
}
bool misreadExclamationMarkAsTypeCharacter;
protected override Token Next()
{
if (misreadExclamationMarkAsTypeCharacter) {
misreadExclamationMarkAsTypeCharacter = false;
return new Token(Tokens.ExclamationMark, Col - 1, Line);
}
unchecked {
int nextChar;
while ((nextChar = ReaderRead()) != -1) {
char ch = (char)nextChar;
if (Char.IsWhiteSpace(ch)) {
int x = Col - 1;
int y = Line;
if (HandleLineEnd(ch)) {
if (lineEnd) {
// second line end before getting to a token
// -> here was a blank line
specialTracker.AddEndOfLine(new Location(x, y));
} else {
lineEnd = true;
return new Token(Tokens.EOL, x, y);
}
}
continue;
}
if (ch == '_') {
if (ReaderPeek() == -1) {
errors.Error(Line, Col, String.Format("No EOF expected after _"));
return new Token(Tokens.EOF);
}
if (!Char.IsWhiteSpace((char)ReaderPeek())) {
int x = Col - 1;
int y = Line;
string s = ReadIdent('_');
lineEnd = false;
return new Token(Tokens.Identifier, x, y, s);
}
ch = (char)ReaderRead();
bool oldLineEnd = lineEnd;
lineEnd = false;
while (Char.IsWhiteSpace(ch)) {
if (HandleLineEnd(ch)) {
lineEnd = true;
break;
}
if (ReaderPeek() != -1) {
ch = (char)ReaderRead();
} else {
errors.Error(Line, Col, String.Format("No EOF expected after _"));
return new Token(Tokens.EOF);
}
}
if (!lineEnd) {
errors.Error(Line, Col, String.Format("Return expected"));
}
lineEnd = oldLineEnd;
continue;
}
if (ch == '#') {
while (Char.IsWhiteSpace((char)ReaderPeek())) {
ReaderRead();
}
if (Char.IsDigit((char)ReaderPeek())) {
int x = Col - 1;
int y = Line;
string s = ReadDate();
DateTime time = new DateTime(1, 1, 1, 0, 0, 0);
try {
time = DateTime.Parse(s, System.Globalization.CultureInfo.InvariantCulture, DateTimeStyles.NoCurrentDateDefault);
} catch (Exception e) {
errors.Error(Line, Col, String.Format("Invalid date time {0}", e));
}
return new Token(Tokens.LiteralDate, x, y, s, time, LiteralFormat.DateTimeLiteral);
} else {
ReadPreprocessorDirective();
continue;
}
}
if (ch == '[') { // Identifier
lineEnd = false;
if (ReaderPeek() == -1) {
errors.Error(Line, Col, String.Format("Identifier expected"));
}
ch = (char)ReaderRead();
if (ch == ']' || Char.IsWhiteSpace(ch)) {
errors.Error(Line, Col, String.Format("Identifier expected"));
}
int x = Col - 1;
int y = Line;
string s = ReadIdent(ch);
if (ReaderPeek() == -1) {
errors.Error(Line, Col, String.Format("']' expected"));
}
ch = (char)ReaderRead();
if (!(ch == ']')) {
errors.Error(Line, Col, String.Format("']' expected"));
}
return new Token(Tokens.Identifier, x, y, s);
}
if (Char.IsLetter(ch)) {
int x = Col - 1;
int y = Line;
char typeCharacter;
string s = ReadIdent(ch, out typeCharacter);
if (typeCharacter == '\0') {
int keyWordToken = Keywords.GetToken(s);
if (keyWordToken >= 0) {
// handle 'REM' comments
if (keyWordToken == Tokens.Rem) {
ReadComment();
if (!lineEnd) {
lineEnd = true;
return new Token(Tokens.EOL, Col, Line, "\n");
}
continue;
}
lineEnd = false;
return new Token(keyWordToken, x, y, s);
}
}
lineEnd = false;
return new Token(Tokens.Identifier, x, y, s);
}
if (Char.IsDigit(ch)) {
lineEnd = false;
return ReadDigit(ch, Col - 1);
}
if (ch == '&') {
lineEnd = false;
if (ReaderPeek() == -1) {
return ReadOperator('&');
}
ch = (char)ReaderPeek();
if (Char.ToUpper(ch, CultureInfo.InvariantCulture) == 'H' || Char.ToUpper(ch, CultureInfo.InvariantCulture) == 'O') {
return ReadDigit('&', Col - 1);
}
return ReadOperator('&');
}
if (ch == '\'' || ch == '\u2018' || ch == '\u2019') {
int x = Col - 1;
int y = Line;
ReadComment();
if (!lineEnd) {
lineEnd = true;
return new Token(Tokens.EOL, x, y, "\n");
}
continue;
}
if (ch == '"') {
lineEnd = false;
int x = Col - 1;
int y = Line;
string s = ReadString();
if (ReaderPeek() != -1 && (ReaderPeek() == 'C' || ReaderPeek() == 'c')) {
ReaderRead();
if (s.Length != 1) {
errors.Error(Line, Col, String.Format("Chars can only have Length 1 "));
}
if (s.Length == 0) {
s = "\0";
}
return new Token(Tokens.LiteralCharacter, x, y, '"' + s + "\"C", s[0], LiteralFormat.CharLiteral);
}
return new Token(Tokens.LiteralString, x, y, '"' + s + '"', s, LiteralFormat.StringLiteral);
}
Token token = ReadOperator(ch);
if (token != null) {
lineEnd = false;
return token;
}
errors.Error(Line, Col, String.Format("Unknown char({0}) which can't be read", ch));
}
return new Token(Tokens.EOF);
}
}
string ReadIdent(char ch)
{
char typeCharacter;
return ReadIdent(ch, out typeCharacter);
}
string ReadIdent(char ch, out char typeCharacter)
{
typeCharacter = '\0';
sb.Length = 0;
sb.Append(ch);
int peek;
while ((peek = ReaderPeek()) != -1 && (Char.IsLetterOrDigit(ch = (char)peek) || ch == '_')) {
ReaderRead();
sb.Append(ch.ToString());
}
if (peek == -1) {
return sb.ToString();
}
if ("%&@!#$".IndexOf((char)peek) != -1) {
typeCharacter = (char)peek;
ReaderRead();
if (typeCharacter == '!') {
peek = ReaderPeek();
if (peek != -1 && (peek == '_' || peek == '[' || char.IsLetter((char)peek))) {
misreadExclamationMarkAsTypeCharacter = true;
}
}
}
return sb.ToString();
}
char PeekUpperChar()
{
return Char.ToUpper((char)ReaderPeek(), CultureInfo.InvariantCulture);
}
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1818:DoNotConcatenateStringsInsideLoops")]
Token ReadDigit(char ch, int x)
{
sb.Length = 0;
sb.Append(ch);
int y = Line;
string digit = "";
if (ch != '&') {
digit += ch;
}
bool ishex = false;
bool isokt = false;
bool issingle = false;
bool isdouble = false;
bool isdecimal = false;
if (ReaderPeek() == -1) {
if (ch == '&') {
errors.Error(Line, Col, String.Format("digit expected"));
}
return new Token(Tokens.LiteralInteger, x, y, sb.ToString() ,ch - '0', LiteralFormat.DecimalNumber);
}
if (ch == '.') {
if (Char.IsDigit((char)ReaderPeek())) {
isdouble = true; // double is default
if (ishex || isokt) {
errors.Error(Line, Col, String.Format("No hexadecimal or oktadecimal floating point values allowed"));
}
while (ReaderPeek() != -1 && Char.IsDigit((char)ReaderPeek())){ // read decimal digits beyond the dot
digit += (char)ReaderRead();
}
}
} else if (ch == '&' && PeekUpperChar() == 'H') {
const string hex = "0123456789ABCDEF";
sb.Append((char)ReaderRead()); // skip 'H'
while (ReaderPeek() != -1 && hex.IndexOf(PeekUpperChar()) != -1) {
ch = (char)ReaderRead();
sb.Append(ch);
digit += Char.ToUpper(ch, CultureInfo.InvariantCulture);
}
ishex = true;
} else if (ReaderPeek() != -1 && ch == '&' && PeekUpperChar() == 'O') {
const string okt = "01234567";
sb.Append((char)ReaderRead()); // skip 'O'
while (ReaderPeek() != -1 && okt.IndexOf(PeekUpperChar()) != -1) {
ch = (char)ReaderRead();
sb.Append(ch);
digit += Char.ToUpper(ch, CultureInfo.InvariantCulture);
}
isokt = true;
} else {
while (ReaderPeek() != -1 && Char.IsDigit((char)ReaderPeek())) {
ch = (char)ReaderRead();;
digit += ch;
sb.Append(ch);
}
}
if (digit.Length == 0) {
errors.Error(Line, Col, String.Format("digit expected"));
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), 0, LiteralFormat.DecimalNumber);
}
if (ReaderPeek() != -1 && "%&SILU".IndexOf(PeekUpperChar()) != -1 || ishex || isokt) {
bool unsigned = false;
if (ReaderPeek() != -1) {
ch = (char)ReaderPeek();
sb.Append(ch);
ch = Char.ToUpper(ch, CultureInfo.InvariantCulture);
unsigned = ch == 'U';
if (unsigned) {
ReaderRead(); // read the U
ch = (char)ReaderPeek();
sb.Append(ch);
ch = Char.ToUpper(ch, CultureInfo.InvariantCulture);
if (ch != 'I' && ch != 'L' && ch != 'S') {
errors.Error(Line, Col, "Invalid type character: U" + ch);
}
}
}
try {
if (isokt) {
ReaderRead();
ulong number = 0L;
for (int i = 0; i < digit.Length; ++i) {
number = number * 8 + digit[i] - '0';
}
if (ch == 'S') {
if (unsigned)
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), (ushort)number, LiteralFormat.OctalNumber);
else
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), (short)number, LiteralFormat.OctalNumber);
} else if (ch == '%' || ch == 'I') {
if (unsigned)
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), (uint)number, LiteralFormat.OctalNumber);
else
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), (int)number, LiteralFormat.OctalNumber);
} else if (ch == '&' || ch == 'L') {
if (unsigned)
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), (ulong)number, LiteralFormat.OctalNumber);
else
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), (long)number, LiteralFormat.OctalNumber);
} else {
if (number > uint.MaxValue) {
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), unchecked((long)number), LiteralFormat.OctalNumber);
} else {
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), unchecked((int)number), LiteralFormat.OctalNumber);
}
}
}
LiteralFormat literalFormat = ishex ? LiteralFormat.HexadecimalNumber : LiteralFormat.DecimalNumber;
if (ch == 'S') {
ReaderRead();
if (unsigned)
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), UInt16.Parse(digit, ishex ? NumberStyles.HexNumber : NumberStyles.Number), literalFormat);
else
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), Int16.Parse(digit, ishex ? NumberStyles.HexNumber : NumberStyles.Number), literalFormat);
} else if (ch == '%' || ch == 'I') {
ReaderRead();
if (unsigned)
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), UInt32.Parse(digit, ishex ? NumberStyles.HexNumber : NumberStyles.Number), literalFormat);
else
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), Int32.Parse(digit, ishex ? NumberStyles.HexNumber : NumberStyles.Number), literalFormat);
} else if (ch == '&' || ch == 'L') {
ReaderRead();
if (unsigned)
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), UInt64.Parse(digit, ishex ? NumberStyles.HexNumber : NumberStyles.Number), literalFormat);
else
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), Int64.Parse(digit, ishex ? NumberStyles.HexNumber : NumberStyles.Number), literalFormat);
} else if (ishex) {
ulong number = UInt64.Parse(digit, NumberStyles.HexNumber);
if (number > uint.MaxValue) {
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), unchecked((long)number), literalFormat);
} else {
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), unchecked((int)number), literalFormat);
}
}
} catch (OverflowException ex) {
errors.Error(Line, Col, ex.Message);
return new Token(Tokens.LiteralInteger, x, y, sb.ToString(), 0, LiteralFormat.None);
}
}
Token nextToken = null; // if we accedently read a 'dot'
if (!isdouble && ReaderPeek() == '.') { // read floating point number
ReaderRead();
if (ReaderPeek() != -1 && Char.IsDigit((char)ReaderPeek())) {
isdouble = true; // double is default
if (ishex || isokt) {
errors.Error(Line, Col, String.Format("No hexadecimal or oktadecimal floating point values allowed"));
}
digit += '.';
while (ReaderPeek() != -1 && Char.IsDigit((char)ReaderPeek())){ // read decimal digits beyond the dot
digit += (char)ReaderRead();
}
} else {
nextToken = new Token(Tokens.Dot, Col - 1, Line);
}
}
if (ReaderPeek() != -1 && PeekUpperChar() == 'E') { // read exponent
isdouble = true;
digit += (char)ReaderRead();
if (ReaderPeek() != -1 && (ReaderPeek() == '-' || ReaderPeek() == '+')) {
digit += (char)ReaderRead();
}
while (ReaderPeek() != -1 && Char.IsDigit((char)ReaderPeek())) { // read exponent value
digit += (char)ReaderRead();
}
}
if (ReaderPeek() != -1) {
switch (PeekUpperChar()) {
case 'R':
case '#':
ReaderRead();
isdouble = true;
break;
case 'D':
case '@':
ReaderRead();
isdecimal = true;
break;
case 'F':
case '!':
ReaderRead();
issingle = true;
break;
}
}
try {
if (issingle) {
return new Token(Tokens.LiteralSingle, x, y, sb.ToString(), Single.Parse(digit, CultureInfo.InvariantCulture), LiteralFormat.DecimalNumber);
}
if (isdecimal) {
return new Token(Tokens.LiteralDecimal, x, y, sb.ToString(), Decimal.Parse(digit, NumberStyles.Currency | NumberStyles.AllowExponent, CultureInfo.InvariantCulture), LiteralFormat.DecimalNumber);
}
if (isdouble) {
return new Token(Tokens.LiteralDouble, x, y, sb.ToString(), Double.Parse(digit, CultureInfo.InvariantCulture), LiteralFormat.DecimalNumber);
}
} catch (FormatException) {
errors.Error(Line, Col, String.Format("{0} is not a parseable number", digit));
if (issingle)
return new Token(Tokens.LiteralSingle, x, y, sb.ToString(), 0f, LiteralFormat.DecimalNumber);
if (isdecimal)
return new Token(Tokens.LiteralDecimal, x, y, sb.ToString(), 0m, LiteralFormat.DecimalNumber);
if (isdouble)
return new Token(Tokens.LiteralDouble, x, y, sb.ToString(), 0.0, LiteralFormat.DecimalNumber);
}
Token token;
try {
token = new Token(Tokens.LiteralInteger, x, y, sb.ToString(), Int32.Parse(digit, ishex ? NumberStyles.HexNumber : NumberStyles.Number), ishex ? LiteralFormat.HexadecimalNumber : LiteralFormat.DecimalNumber);
} catch (Exception) {
try {
token = new Token(Tokens.LiteralInteger, x, y, sb.ToString(), Int64.Parse(digit, ishex ? NumberStyles.HexNumber : NumberStyles.Number), ishex ? LiteralFormat.HexadecimalNumber : LiteralFormat.DecimalNumber);
} catch (FormatException) {
errors.Error(Line, Col, String.Format("{0} is not a parseable number", digit));
// fallback, when nothing helps :)
token = new Token(Tokens.LiteralInteger, x, y, sb.ToString(), 0, LiteralFormat.DecimalNumber);
} catch (OverflowException) {
errors.Error(Line, Col, String.Format("{0} is too long for a integer literal", digit));
// fallback, when nothing helps :)
token = new Token(Tokens.LiteralInteger, x, y, sb.ToString(), 0, LiteralFormat.DecimalNumber);
}
}
token.next = nextToken;
return token;
}
void ReadPreprocessorDirective()
{
Location start = new Location(Col - 1, Line);
string directive = ReadIdent('#');
string argument = ReadToEndOfLine();
this.specialTracker.AddPreprocessingDirective(new PreprocessingDirective(directive, argument.Trim(), start, new Location(start.X + directive.Length + argument.Length, start.Y)));
}
string ReadDate()
{
char ch = '\0';
sb.Length = 0;
int nextChar;
while ((nextChar = ReaderRead()) != -1) {
ch = (char)nextChar;
if (ch == '#') {
break;
} else if (ch == '\n') {
errors.Error(Line, Col, String.Format("No return allowed inside Date literal"));
} else {
sb.Append(ch);
}
}
if (ch != '#') {
errors.Error(Line, Col, String.Format("End of File reached before Date literal terminated"));
}
return sb.ToString();
}
string ReadString()
{
char ch = '\0';
sb.Length = 0;
int nextChar;
while ((nextChar = ReaderRead()) != -1) {
ch = (char)nextChar;
if (ch == '"') {
if (ReaderPeek() != -1 && ReaderPeek() == '"') {
sb.Append('"');
ReaderRead();
} else {
break;
}
} else if (ch == '\n') {
errors.Error(Line, Col, String.Format("No return allowed inside String literal"));
} else {
sb.Append(ch);
}
}
if (ch != '"') {
errors.Error(Line, Col, String.Format("End of File reached before String terminated "));
}
return sb.ToString();
}
void ReadComment()
{
Location startPos = new Location(Col, Line);
sb.Length = 0;
StringBuilder curWord = specialCommentHash != null ? new StringBuilder() : null;
int missingApostrophes = 2; // no. of ' missing until it is a documentation comment
int nextChar;
while ((nextChar = ReaderRead()) != -1) {
char ch = (char)nextChar;
if (HandleLineEnd(ch)) {
break;
}
sb.Append(ch);
if (missingApostrophes > 0) {
if (ch == '\'' || ch == '\u2018' || ch == '\u2019') {
if (--missingApostrophes == 0) {
specialTracker.StartComment(CommentType.Documentation, startPos);
sb.Length = 0;
}
} else {
specialTracker.StartComment(CommentType.SingleLine, startPos);
missingApostrophes = 0;
}
}
if (specialCommentHash != null) {
if (Char.IsLetter(ch)) {
curWord.Append(ch);
} else {
string tag = curWord.ToString();
curWord.Length = 0;
if (specialCommentHash.ContainsKey(tag)) {
Location p = new Location(Col, Line);
string comment = ch + ReadToEndOfLine();
this.TagComments.Add(new TagComment(tag, comment, p, new Location(Col, Line)));
sb.Append(comment);
break;
}
}
}
}
if (missingApostrophes > 0) {
specialTracker.StartComment(CommentType.SingleLine, startPos);
}
specialTracker.AddString(sb.ToString());
specialTracker.FinishComment(new Location(Col, Line));
}
Token ReadOperator(char ch)
{
int x = Col - 1;
int y = Line;
switch(ch) {
case '+':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.PlusAssign, x, y);
default:
break;
}
return new Token(Tokens.Plus, x, y);
case '-':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.MinusAssign, x, y);
default:
break;
}
return new Token(Tokens.Minus, x, y);
case '*':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.TimesAssign, x, y);
default:
break;
}
return new Token(Tokens.Times, x, y, "*");
case '/':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.DivAssign, x, y);
default:
break;
}
return new Token(Tokens.Div, x, y);
case '\\':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.DivIntegerAssign, x, y);
default:
break;
}
return new Token(Tokens.DivInteger, x, y);
case '&':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.ConcatStringAssign, x, y);
default:
break;
}
return new Token(Tokens.ConcatString, x, y);
case '^':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.PowerAssign, x, y);
default:
break;
}
return new Token(Tokens.Power, x, y);
case ':':
return new Token(Tokens.Colon, x, y);
case '=':
return new Token(Tokens.Assign, x, y);
case '<':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.LessEqual, x, y);
case '>':
ReaderRead();
return new Token(Tokens.NotEqual, x, y);
case '<':
ReaderRead();
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.ShiftLeftAssign, x, y);
default:
break;
}
return new Token(Tokens.ShiftLeft, x, y);
}
return new Token(Tokens.LessThan, x, y);
case '>':
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.GreaterEqual, x, y);
case '>':
ReaderRead();
if (ReaderPeek() != -1) {
switch (ReaderPeek()) {
case '=':
ReaderRead();
return new Token(Tokens.ShiftRightAssign, x, y);
default:
break;
}
}
return new Token(Tokens.ShiftRight, x, y);
}
return new Token(Tokens.GreaterThan, x, y);
case ',':
return new Token(Tokens.Comma, x, y);
case '.':
// Prevent OverflowException when Peek returns -1
int tmp = ReaderPeek();
if (tmp > 0 && Char.IsDigit((char)tmp)) {
return ReadDigit('.', Col);
}
return new Token(Tokens.Dot, x, y);
case '(':
return new Token(Tokens.OpenParenthesis, x, y);
case ')':
return new Token(Tokens.CloseParenthesis, x, y);
case '{':
return new Token(Tokens.OpenCurlyBrace, x, y);
case '}':
return new Token(Tokens.CloseCurlyBrace, x, y);
case '?':
return new Token(Tokens.QuestionMark, x, y);
case '!':
return new Token(Tokens.ExclamationMark, x, y);
}
return null;
}
public override void SkipCurrentBlock(int targetToken)
{
int lastKind = -1;
int kind = base.lastToken.kind;
while (kind != Tokens.EOF &&
!(lastKind == Tokens.End && kind == targetToken))
{
lastKind = kind;
NextToken();
kind = lastToken.kind;
}
}
}
}
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