public Ast Parse(Tokenizer tokenizer, ErrorRecord errorRecord)
{
symbolStack.Push(parsingTable.LastSymbol);
symbolStack.Push(parsingTable.FirstSymbol);
Token lastToken = null;
while (symbolStack.Count != 0)
{
if (EnableStackTrace)
{
TraceStack(tokenizer.Peek(), symbolStack, semanticStack);
}
Symbol symbol = symbolStack.Pop();
Token token = tokenizer.Peek();
if (token is ErrorToken)
{
errorRecord.AddLexicalError(token as ErrorToken, StackTrace);
return(null);
}
if (symbol.ToSymbolType() == SymbolType.Token)
{
if (symbol == token.Symbol)
{
lastToken = tokenizer.Pop();
}
else
{
errorRecord.AddSyntaxError(symbol, token, StackTrace);
return(null);
}
}
else if (symbol.ToSymbolType() == SymbolType.NonTerminal)
{
var rule = parsingTable[symbol, token.Symbol];
if (rule == null)
{
errorRecord.AddSyntaxError(symbol, token, StackTrace);
return(null);
}
else
{
symbolStack.Push(rule.Reverse);
}
}
else if (symbol.ToSymbolType() == SymbolType.Semantic)
{
astFactory.ProcessAction(semanticStack, symbol, lastToken);
}
}
return(semanticStack.Peek());
}