std::string TreeBuilder::getExpectedTokensGrammar() const
{
std::vector<std::string> tokens = getExpectedTokens();
if (tokens.empty())
return "No productions expected";
std::string result(tokens.at(0));
if (tokens.size() > 1)
{
result += ": [\n";
for (std::size_t i = 1; i < tokens.size(); ++i)
{
result += "\t" + tokens[i] + ",\n";
}
result.erase(result.end() - 1);
return result + "\n]";
}
return result;
}
void PlSqlParser::correctError(int *token, ParsingTableRow *row, ParsingTableAction **actionOnCurrentToken)
{
//qDebug("--------started error recovery--------------");
bool reservedWord = parsingTable->isReservedWord(scanner->getTokenLexeme());
if(*token!=PLS_SEMI){
*actionOnCurrentToken=row->actions->value(PLS_NOT_SEMI, 0);
if(!reservedWord){
replaceKeywordWithIdentifier(*token, row, actionOnCurrentToken);
}
}
if(*actionOnCurrentToken == 0 && !this->strict){ //try to recognize major constructs
//read input until we encounter one of (first of) PLS_SEMI, END opt_identifier PLS_SEMI
//while reading add all read tokens to token stack
QList<TokenInfo*> reduceTokens;
bool hasNonUsedReduceTokens = false;
do{
if(!reservedWord || countOnLastPosition>maxStayCountOnSamePosition){
reduceTokens.prepend(createTokenInfo(*token));
hasNonUsedReduceTokens = true;
}
if(*token == PLS_SEMI || reservedWord){
int reducedConstruct = 0;
QList<int> expectedTerminals = getExpectedTokens(row).first;
//bool waitingForSemicolon = (expectedTerminals.size()==1 && expectedTerminals[0]==PLS_SEMI);
bool waitingForSemicolon = expectedTerminals.contains(PLS_SEMI);
if(reservedWord && countOnLastPosition<=maxStayCountOnSamePosition &&
!waitingForSemicolon){ //if current token is reserved word, try to reduce expression first
int constuctsToCheck[] = {R_EXPRESSION, R_DECLARATION, R_STATEMENT};
reducedConstruct = reduceMajorConstruct(reduceTokens, constuctsToCheck, 3);
}else{ //on semicolon try to reduce declaration or statement
int constuctsToCheck[] = {R_DECLARATION, R_STATEMENT};
reducedConstruct = reduceMajorConstruct(reduceTokens, constuctsToCheck, 2);
}
if(reducedConstruct){
//read next token for parser to operate
if(!reservedWord || countOnLastPosition>maxStayCountOnSamePosition){
*token = scanner->getNextToken();
if(*token == PLS_SEMI){
correctError(token, row, actionOnCurrentToken);
}
}
ParsingTableRow *newRow=parsingTable->rows.at(stack.top()); //reduceMajorConstruct pushed new gotoState into stack
*actionOnCurrentToken=(*newRow->actions).value(*token, 0);
replaceKeywordWithIdentifier(*token, newRow, actionOnCurrentToken);
}else{
qDeleteAll(reduceTokens);
}
hasNonUsedReduceTokens = false;
break;
}
*token = scanner->getNextToken();
reservedWord = parsingTable->isReservedWord(scanner->getTokenLexeme());
}while(*token != PLS_E_O_F);
if(hasNonUsedReduceTokens){
qDeleteAll(reduceTokens);
}
}
if(scanner->getTokenStartPos() == lastErrorPosition){
++countOnLastPosition;
}else if(countOnLastPosition > 0){
countOnLastPosition = 0;
}
lastErrorPosition = scanner->getTokenStartPos();
//qDebug("--------completed error recovery--------------");
}
