/// <summary>
/// get next token and check if its type is expected..
/// </summary>
/// <param name="type"></param>
/// <returns></returns>
bool Match(int type)
{
bool flag;
currentToken = GetNextToken();
flag = (currentToken.TokenTypes == type);
//--currentTokenIndex;
return flag;
}
bool Match(char ch)
{
int type = Convert.ToInt32(ch);
bool flag;
currentToken = GetNextToken();
flag = (currentToken.TokenTypes == type);
//--currentTokenIndex;
return flag;
}
/// <summary>
/// 4. var-declaration → type-specifier ID(,...); | type-specifier ID [ NUM ](,...);
/// 5. type-specifier → int | void
/// </summary>
/// <returns></returns>
TreeNode VarDeclaration()
{
// now, cToken.str == ";", "," or "["
Word iToken = idNameToken as Word;
TreeNode temp = new TreeNode(NodeKind.varK, (TokenType)typeToken.TokenTypes, iToken.Lexeme, currentToken.LineNumber, scope);
if (CheckCurrentToken('[')) {
currentToken = GetNextToken();//must NUMber
if (!CheckCurrentToken(TokenType.NUMBER)) {
ErrorRecord(ParseErrorType.MissingArraySize);
ConsumeUntil(";", "}");
//error
/*scan->add_err();
sprintf(msg_temp,
"Syntax error: missing array size in declaration of array %s[]",
iToken.str.c_str());
outputMsg(scan->lineno(), msg_temp);
delete temp;
consumeUntil(SEMI, RBRACE); // error recovery in global declaration
return NULL;*/
return null;
}
temp.IsArray = true;
Number num = currentToken as Number;
temp.ArraySize = Convert.ToInt32(num.Lexeme);
if (!Match(Convert.ToInt32(']'))) {
ErrorRecord(ParseErrorType.MissingRBracketInArray);
--currentTokenIndex;
// need ']'
/*
scan->add_err();
sprintf(msg_temp,
"Syntax error: missing \']\' in declaration of array %s[]",
iToken.str.c_str());
scan->push();
*/
}
currentToken = GetNextToken();// ";" or ","
}
if (CheckCurrentToken(',')) {
idNameToken = currentToken = GetNextToken();//next id
if (idNameToken.TokenTypes != Convert.ToInt32( TokenType.ID)) {
//错误处理
ErrorRecord(ParseErrorType.ReservedToken);
ConsumeUntil(";", "}");
return temp;
}
currentToken = GetNextToken();//expected ";", ",", "["
if (CheckCurrentToken(';')||
CheckCurrentToken(',') ||
CheckCurrentToken('['))
{
temp.Sibling = VarDeclaration();
}
else {
//错误处理
ErrorRecord(ParseErrorType.MissingSemi);
--currentTokenIndex;
return temp;
}
}
else if ( !CheckCurrentToken(';')) {
//错误处理
ErrorRecord(ParseErrorType.MissingSemiAfterDeclarationSequence);
ConsumeUntil(";", "}");
}
return temp;
}
/// <summary>
/// 11. local-declarations→ local-declarations var-declaration | empty
/// </summary>
/// <returns></returns>
TreeNode LocalDeclarations()
{
TreeNode temp = null;
idNameToken = currentToken = GetNextToken();
if (idNameToken.TokenTypes != Convert.ToInt32(TokenType.ID))
{
//错误处理
ErrorRecord(ParseErrorType.ReservedToken);
ConsumeUntil(";");
return null;
}
currentToken = GetNextToken();//';', '[', ','
if (CheckCurrentToken(';') || CheckCurrentToken('[') || CheckCurrentToken(','))
{
temp = VarDeclaration();
}
else
{
//错误处理
ErrorRecord(ParseErrorType.MissingSemi);
--currentTokenIndex;
}
return temp;
}
/// <summary>
/// sub_compoundstmt → ID; | call; | expression_stmt
/// </summary>
/// <returns></returns>
TreeNode SubcompoundStmt()
{
TreeNode temp = null;
// cout << "Subcompound_stmt()" <<endl;
idNameToken = currentToken;
currentToken = GetNextToken();
if (CheckCurrentToken('('))
{ // call statement
temp = Call();
if (!Match(';'))
{
ErrorRecord(ParseErrorType.MissingSemiAfterFunCall);
--currentTokenIndex;
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \';\' after fun call");
//scan->push();
}
}
else
{
--currentTokenIndex;
currentToken = idNameToken;
temp = ExpressionStmt();
}
return temp;
}
/// <summary>
/// 19. var → ID | ID [ expression ]
/// </summary>
/// <returns></returns>
TreeNode Var()
{
Word iToken = idNameToken as Word;
TreeNode temp = new TreeNode(ExpKind.IDK, (TokenType)currentToken.TokenTypes, iToken.Lexeme, currentToken.LineNumber, scope);
// "["
currentToken = GetNextToken();
if (CheckCurrentToken('['))
{
temp.IsArray = true;
currentToken = GetNextToken();
temp.Child[0] = Expression();
if (!Match(']'))
{
ErrorRecord(ParseErrorType.MissingRBracket);
--currentTokenIndex;
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \']\'");
//scan->push();
}
//改动，不把数组的大小变成一个单独的节点。
temp.ArraySize = Convert.ToInt16(temp.Child[0].Name.ToString());
temp.Child[0] = null;
}
else
{
--currentTokenIndex;
}
return temp;
}
/// <summary>
/// 3. declaration → var-declaration | fun-declaration
/// </summary>
/// <returns></returns>
TreeNode Declaration()
{
scope = "global"; // use global fun or var
TreeNode temp = null;
typeToken = currentToken;
currentToken = GetNextToken();
idNameToken = currentToken;
if (idNameToken.TokenTypes != Convert.ToInt32(TokenType.ID))
{
ErrorRecord(ParseErrorType.ReservedToken);
ConsumeUntil(";", "}");
//错误处理
//scan->add_err();
//sprintf(msg_temp, "Syntax error: %s is a reserved token", iToken.str.c_str());
//outputMsg(scan->lineno(), msg_temp);
//consumeUntil(SEMI, RBRACE);
}
else {
currentToken = GetNextToken();// expected a '(', '[' or ','
if (CheckCurrentToken('(')) {
// '(' is fun declaration
temp = FunDeclaration();
}
else if (CheckCurrentToken(';')||
CheckCurrentToken(',')||
CheckCurrentToken('['))
{
temp = VarDeclaration();
}
else {
ErrorRecord(ParseErrorType.MissingSemi);
ConsumeUntil(";", "}");
//错误处理
//scan->add_err();
//sprintf(msg_temp, "Syntax error: missing \';\' after indentifer %s",iToken.str.c_str());
//outputMsg(scan->lineno(), msg_temp);
//consumeUntil(SEMI, RBRACE);
}
}
return temp;
}
/// <summary>
/// 17. return-stmt → return; | return expression;
/// </summary>
/// <returns></returns>
TreeNode ReturnStmt()
{
// cToken.str == "return"
Word NToken = currentToken as Word;
TreeNode temp = new TreeNode(StmtKind.returnK, NToken.Lexeme, currentToken.LineNumber, scope);
currentToken = GetNextToken();
//TreeNode temp11 = new TreeNode(StmtKind.returnK, NToken.Lexeme, currentToken.LineNumber, scope);
//TreeNode temp1 = new TreeNode(StmtKind.returnK, NToken.Lexeme, currentToken.LineNumber, scope);
if (!CheckCurrentToken(';')) {
temp.Child[0] = Expression();
if (!Match(';')) {
//错误处理
ErrorRecord(ParseErrorType.MissingSemiInReturn);
--currentTokenIndex;
}
}
return temp;
}
/// <summary>
/// 10. compound-stmt → { local-declarations statement-list }
/// </summary>
/// <returns></returns>
TreeNode CompoundStmt()
{
TreeNode first = null;
TreeNode last = null;
TreeNode temp = null;
bool noBraces = false;
if (!Match(Convert.ToInt32('{')))
{// match "{"
noBraces = true;
--currentTokenIndex;
}
// local-declarations
while (true)
{
typeToken = currentToken = GetNextToken();
if (CheckCurrentToken(TokenType.INT) ||
CheckCurrentToken(TokenType.VOID))
{
temp = LocalDeclarations();
}
else
{
--currentTokenIndex;
break;
}
if (noBraces)
return temp;
if (temp != null)
{
if (first == null)
{
first = temp;
last = temp.LastSibling();
}
else
{
last.Sibling = temp;
last = temp.LastSibling();
}
}
}
//currentToken = GetNextToken();
currentToken = GetNextToken();
while (true) {
temp = null;
if (CheckCurrentToken('}')) {
if (noBraces) {
//错误处理
ErrorRecord(ParseErrorType.UnpairedRBrace);
}
break;
}
if (CheckCurrentToken(TokenType.EOF)) {
//错误处理
ErrorRecord(ParseErrorType.MissingRBraceBeforeEOF);
--currentTokenIndex;
break;
}
switch (currentToken.TokenTypes) {
case (Int32)TokenType.READ:
temp = ReadStmt();
break;
case (Int32)TokenType.WRITE:
temp = WriteStmt();
break;
case (Int32)(';'):
case (Int32)TokenType.NUMBER:
case (Int32)('('):
temp = ExpressionStmt();
break;
case (Int32)TokenType.ID:
temp = SubcompoundStmt();
break;
case (Int32)TokenType.IF:
temp = IfStmt();
// currentToken = GetNextToken();
break;
case (Int32)TokenType.WHILE:
temp = WhileStmt();
break;
case (Int32)TokenType.RETURN:
temp = ReturnStmt();
break;
case (Int32)TokenType.ELSE:
//错误处理
ErrorRecord(ParseErrorType.UnpairedElseStatement);
ConsumeUntil(";", "}");
//scan->add_err();
//outputMsg(scan->lineno(), " unpaired \'else\' statement");
//consumeUntil(SEMI, RBRACE);
break;
default:
//错误处理
ErrorRecord(ParseErrorType.UndefinedSymbol);
ConsumeUntil(";", "}");
//scan->add_err();
//sprintf(msg_temp, "Syntax error: undefined symbol \"%s\"", cToken.str.c_str());
//outputMsg(scan->lineno(), msg_temp);
//consumeUntil(SEMI, RBRACE);
break;
}
if (noBraces)
return temp;//// no braces
if (temp != null) {
if (first == null)
{
first = temp;
last = temp.LastSibling();
}
else {
last.Sibling = temp;
last = temp.LastSibling();
}
}
currentToken = GetNextToken();
}
return first;
}
private void ConsumeUntil(string type)
{
while (currentToken.TokenInfo != type && currentToken.TokenInfo != "EOF")
currentToken = GetNextToken();
}
/// <summary>
/// 28. args → arg-list | empty & 29. arg-list → arg-list , expression | expression
/// </summary>
/// <returns></returns>
private TreeNode Args()
{
TreeNode first = null;
TreeNode temp = null;
currentToken = GetNextToken();
if (CheckCurrentToken(')')) {
--currentTokenIndex;
return null;
}
while (true) {
if ((temp = Expression()) != null)
{
if (first == null) first = temp;
else
{
temp.Sibling = first;
first = temp;
}
}
currentToken = GetNextToken();
if (currentToken.TokenTypes == Convert.ToInt32(','))
{
currentToken = GetNextToken();
}
else
{
break;
}
}
--currentTokenIndex;
return first;
}
/// <summary>
/// 31. write → write( int );
/// </summary>
/// <returns></returns>
TreeNode WriteStmt()
{
TreeNode temp = null;
if (!Match('('))
{
ErrorRecord(ParseErrorType.MissingRParenthesis);
ConsumeUntil(";", "}");
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \'(\'");
//consumeUntil(SEMI, RBRACE);
return null;
}
temp = new TreeNode(StmtKind.writeK, "write", currentToken.LineNumber, scope);
currentToken = GetNextToken();
if ((temp.Child[0] = Expression()) != null)
{
temp.Child[0].Father = temp;
}
if (!Match(')'))
{
ErrorRecord(ParseErrorType.MissingRParenthesis);
ConsumeUntil(";", "}");
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \')\'");
//consumeUntil(SEMI, RBRACE);
return temp;
}
if (!Match(';'))
{
ErrorRecord(ParseErrorType.MissingSemiOnly);
--currentTokenIndex;
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \';\'");
//scan->push();
}
return temp;
}
/// <summary>
/// 16. iteration-stmt → while ( expression ) statement
/// </summary>
/// <returns></returns>
TreeNode WhileStmt()
{
Word CToken = currentToken as Word;
TreeNode temp = new TreeNode(StmtKind.whileK,CToken.Lexeme,currentToken.LineNumber,scope);
TreeNode p = null;
if (!Match('('))
{
ErrorRecord(ParseErrorType.MissingLParenthesisInWhile);
/*
// while (
scan->add_err(); // add error count,
// out put the error message
outputMsg(scan->lineno(), "Syntax error: missing \'(\' in \"while\" statement");
*/
}
else {
currentToken = GetNextToken();
}
// cToken should be the first token of expression now ...
temp.Child[0] = Expression();
if (temp.Child[0] != null)
temp.Child[0].Father = temp;
if (!Match(')')) {
//while()
//错误处理
ErrorRecord(ParseErrorType.MissingRParenthesisInWhile);
}
p = temp.Child[1] = CompoundStmt();
if (p != null)
p.Father = temp;
while (p != null && p.Sibling != null) {
p = p.Sibling;
p.Father = temp;
}
return temp;
}
/// <summary>
/// 7. params → params-list | void
/// 8. param-list→ param-list, param | param
/// 9. param→ type-specifier ID | type-specifier ID [ ]
/// </summary>
/// <returns></returns>
TreeNode Params()
{
TreeNode first = null;
TreeNode temp = null;
typeToken = currentToken = GetNextToken();
if (CheckCurrentToken(')')) {
--currentTokenIndex;//scan->push();
return temp;//null
}
if (typeToken.TokenTypes == Convert.ToInt32(TokenType.VOID))
{
if (Match(Convert.ToInt32( ')')))
{
--currentTokenIndex;
return temp; // NULL
}
else
{
--currentTokenIndex;//scan->push(); // not ")"
}
}
while (typeToken.TokenTypes == Convert.ToInt32(TokenType.INT) ||
typeToken.TokenTypes == Convert.ToInt32(TokenType.VOID))
{
idNameToken = currentToken = GetNextToken();
if (idNameToken.TokenTypes != Convert.ToInt32(TokenType.ID))
{
//error
ErrorRecord(ParseErrorType.InvalidParameter);
}
else {
Word iToken = idNameToken as Word;
temp = new TreeNode(NodeKind.paramK, (TokenType)typeToken.TokenTypes, iToken.Lexeme, currentToken.LineNumber, scope);
temp.Sibling = first;
first = temp;
}
currentToken = GetNextToken();
if (CheckCurrentToken('[')) {
temp.IsArray = true;
if (!Match(Convert.ToInt32(']')))
{
//错误处理
ErrorRecord(ParseErrorType.MissingArrayParameter);
ConsumeUntil(";", ")");
}
else {
currentToken = GetNextToken();//','
}
}
if (CheckCurrentToken(')')) {//')'
break;//')'
}
else if (CheckCurrentToken(','))//','
{
typeToken = currentToken = GetNextToken();
}
else {
break;
}
}
--currentTokenIndex; //next is ')'
return first;
}
/// <summary>
/// 2. declaration-list → declaration-list declaration | declaration
/// </summary>
/// <returns></returns>
TreeNode DeclarationList()
{
TreeNode program = null;
TreeNode last = null;
TreeNode temp = null;
currentToken = GetNextToken();
while (!CheckCurrentToken(TokenType.EOF)) {
if (!CheckCurrentToken(TokenType.INT)&&
!CheckCurrentToken(TokenType.VOID) &&!CheckCurrentToken(';'))
{
ErrorRecord(ParseErrorType.InvalidType);
ConsumeUntil(";","}");
//错误处理
//scan->add_err();
//sprintf(msg_temp, "Syntax error: invalid type \'%s\'",
// cToken.str.c_str());
//outputMsg(scan->lineno(), msg_temp);
//consumeUntil(SEMI, RBRACE); // ';', '}'
}
else if ((temp = Declaration()) != null)
{
if (program == null)
{
program = temp;
last = temp.LastSibling();
}
else
{
last.Sibling = temp;
last = temp.LastSibling();
}
}
currentToken = GetNextToken();
}
return program;
}
/// <summary>
/// 30. read → read( int );
/// </summary>
/// <returns></returns>
TreeNode ReadStmt()
{
// currentToken.str == "read"
TreeNode temp = null;
if (!Match('('))
{
ErrorRecord(ParseErrorType.MissingLParenthesis);
ConsumeUntil(";","}");
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \'(\'");
//consumeUntil(SEMI, RBRACE);
return null;
}
idNameToken = currentToken = GetNextToken();
if (!CheckCurrentToken(TokenType.ID))
{
//错误处理
ErrorRecord(ParseErrorType.BadArgument);
ConsumeUntil(";", "}");
return null;
}
temp = new TreeNode(StmtKind.readK, "read", currentToken.LineNumber, scope);
if ((temp.Child[0] = Var()) != null)
{
temp.Child[0].Father = temp;
}
if (!Match(')'))
{
ErrorRecord(ParseErrorType.MissingRParenthesis);
ConsumeUntil(";", "}");
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \')\'");
//consumeUntil(SEMI, RBRACE);
return temp;
}
if (!Match(';'))
{
ErrorRecord(ParseErrorType.MissingSemiOnly);
--currentTokenIndex;
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \';\'");
//scan->push();
}
return temp;
}
/// <summary>
/// 18. expression → var = expression | simple-expression
/// </summary>
/// <returns></returns>
private TreeNode Expression()
{
// cToken == (, k_ID, k_NUM
TreeNode temp = SimpleExpression();
TreeNode p = temp;
currentToken = GetNextToken();
if (CheckCurrentToken('='))
{
if (temp.Type != TokenType.ID && (Int32)temp.Type != (Int32)('='))
{
//错误处理
ErrorRecord(ParseErrorType.LeftID);
ConsumeUntil(";", ")");
return null;
}
p = new TreeNode(ExpKind.OpK, (TokenType)currentToken.TokenTypes, currentToken.TokenInfo, currentToken.LineNumber, scope);
p.Child[0] = temp;
if (p.Child[0] != null)
p.Child[0].Father = p;
currentToken = GetNextToken();
p.Child[1] = Expression();
if (p.Child[1] != null)
p.Child[1].Father = p;
}
else {
--currentTokenIndex;
}
return p;
}
/// <summary>
/// 20. simple-expression → additive-expression relop additive-expression
/// |additive-expression
/// 21. relop →<= | < | > | >= | == | !=
/// </summary>
/// <returns></returns>
private TreeNode SimpleExpression()
{
TreeNode p = AdditiveExpression();
currentToken = GetNextToken();
if (CheckCurrentToken(TokenType.LESSEQUAL) ||
CheckCurrentToken('<') || CheckCurrentToken('>') ||
CheckCurrentToken(TokenType.GREATERQUAL) || CheckCurrentToken(TokenType.EQUAL) ||
CheckCurrentToken(TokenType.NOTEQUAL))
{
TreeNode temp = new TreeNode(ExpKind.OpK, (TokenType)currentToken.TokenTypes, currentToken.TokenInfo, currentToken.LineNumber, scope);
temp.Child[0] = p;
p = temp;
if (p.Child[0] != null)
p.Child[0].Father = p;
currentToken = GetNextToken();
p.Child[1] = AdditiveExpression();
if (p.Child[1] != null) {
p.Child[1].Father = p;
}
}
else {
--currentTokenIndex;
}
return p;
}
/// <summary>
/// 26. factor → ( expression ) | var | call | NUM
/// </summary>
/// <returns></returns>
private TreeNode Factor()
{
TreeNode temp = null;
switch (currentToken.TokenTypes)
{
case (Int32)TokenType.NUMBER:
Number NToken = currentToken as Number;
temp = new TreeNode(ExpKind.ConstK, (TokenType)currentToken.TokenTypes, NToken.Lexeme , currentToken.LineNumber, scope);
break;
case (Int32)TokenType.ID:
idNameToken = currentToken;
currentToken = GetNextToken();
if (CheckCurrentToken('(')) temp = Call();
else
{
--currentTokenIndex;
temp = Var();
}
break;
case (Int32)('('):
currentToken = GetNextToken();
temp = Expression();
if (!Match(')'))
{
ErrorRecord(ParseErrorType.MissingRParenthesis);
--currentTokenIndex;
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax Error: missing \')\'");
//scan->push();
}
break;
default:
ErrorRecord(ParseErrorType.ExpressionIsUnexpected);
ConsumeUntil(";", "}");
//scan->add_err();
//sprintf(msg_temp, "Syntax error: \'%s\' expression is unexpected!", cToken.str.c_str());
//outputMsg(scan->lineno(), msg_temp);
//consumeUntil(SEMI, RBRACE);
break;
}
return temp;
}
/// <summary>
/// 24. term → term mulop factor | factor
/// 25. mulop →* | /
/// </summary>
/// <returns></returns>
private TreeNode Term()
{
TreeNode p = Factor();
currentToken = GetNextToken();
while (CheckCurrentToken('*') || CheckCurrentToken('/') || CheckCurrentToken('%')) {
TreeNode temp = new TreeNode(ExpKind.OpK, (TokenType)currentToken.TokenTypes, currentToken.TokenInfo, currentToken.LineNumber, scope);
temp.Child[0] = p;
p = temp;
if (p.Child[0] != null)
p.Child[0].Father = p;
currentToken = GetNextToken();
p.Child[1] = Factor();
if (p.Child[1] != null)
{
p.Child[1].Father = p;
}
currentToken = GetNextToken();
}
--currentTokenIndex;
return p;
}
/// <summary>
/// 15. selection-stmt → if (expression ) s tatement
/// | if ( expression ) statement else statement
/// </summary>
/// <returns></returns>
TreeNode IfStmt()
{
Word CToken = currentToken as Word;
TreeNode temp = new TreeNode(StmtKind.ifK,CToken.Lexeme,currentToken.LineNumber,scope);
TreeNode p = null;
if (!Match('('))
{ // if (
//错误处理
ErrorRecord(ParseErrorType.MissingLParenthesisInIf);
//scan->add_err();
//outputMsg(scan->lineno(), "Syntax error: missing \'(\' in \"if\" statement");
}
else
{
currentToken = GetNextToken();
}
temp.Child[0] = Expression();
if (temp.Child[0] != null)
temp.Child[0].Father = temp;
if (!Match(')')) {
//错误处理
ErrorRecord(ParseErrorType.MissingRParenthesisInIf);
}
p = temp.Child[1] = CompoundStmt();
if (p != null)
p.Father = temp;
while (p != null && p.Sibling != null) {
p = p.Sibling;
p.Father = temp;
}
currentToken = GetNextToken();
if (CheckCurrentToken(TokenType.ELSE))
{
p = temp.Child[2] = CompoundStmt();
if (p != null) p.Father = temp;
while (p!=null && p.Sibling!=null)
{
p = p.Sibling;
p.Father = temp;
}
}
else {
// if has no 'else' statement, push the next token back
--currentTokenIndex;
}
return temp;
}
/// <summary>
/// 把token加到token链表
/// </summary>
/// <param name="token">token类型</param>
private void AddToTokenList(Token token)
{
token.LineNumber += 1;
token.ColumnNumber += 1;
tokenList.Add(token);
}
public void ParseLL1(List<Token> tokenList)
{
///*语法树的根节点*/
TreeNode rootPointer;
currentToken = GetNextToken();
int pNum = 0; //纪录选中的产生式编号
LL1Table.CreatLL1Table();
///*指向整个语法树根节点的指针，由它得到语法树*/
rootPointer = OperateTree.NewRootNode();
treeStack.Push(rootPointer);
///*从这里开始进行语法分析和语法树的生成*/
elementStack.Push(new LL1StackElement(true, NonTerminalType.Program,-1));
/*取一个token*/
int lineNum = currentToken.LineNumber;
while (elementStack.Count != 0)
{
LL1StackElement element = (LL1StackElement)elementStack.Peek();
/*检测终极符是否匹配*/
if (element.Flag == false)
{
if (Convert.ToInt16(element.TokenType) == currentToken.TokenTypes)
{
elementStack.Pop();
currentToken = GetNextToken();
if (currentToken == null) {//空
break;
}
//lineno = currentToken.lineshow;
}
else
{
//syntaxError("unexpected token -> ");
//fprintf(listing, " %s", currentToken.Sem);
//fprintf(listing, " ");
////printf("terminal not match!\n");
////printf("%d\n",stacktopT);
//exit(0);
}
}
else
{ /*根据非终极符和栈中符号进行预测*/
pNum = LL1Table.LL1table[Convert.ToInt16(element.NonTerminalType), currentToken.TokenTypes];
if (pNum == 39)
{
//向前看一个 读完i返回原处
}
else if (pNum == 7)
{
//向前看两个 读完i返回原处
}
elementStack.Pop();
// if (0==pnum)
// { printf("no predict!\n");
// printf("%d\n",stacktopN);
// }
Predict(pNum);
}
}
if (tokenList[i].TokenTypes != Convert.ToInt16(TokenType.EOF))
{
//syntaxError("Code ends before file \n");
}
//return rootPointer;
}