// Create as much of the parse tree as possible.
public override int CreateParseSubTree(ref CLexicalAnalyzer plexAnal, ref CSymbolTable pSymbolTable)
{
CToken pToken = null;
{
//Munch a <IF>
if ((CLexicalAnalyzer.LEX_FAIL == plexAnal.GetNextToken(ref pToken, ref pSymbolTable)) ||
pToken == null || !pToken.IsIFStatement())
{
//throw(C_UM_ERROR_INTERNALERR);
}
//Munch a <(>
if ((CLexicalAnalyzer.LEX_FAIL == plexAnal.GetNextToken(ref pToken, ref pSymbolTable)) ||
pToken == null || (pToken.GetSubType() != RUL_TOKEN_SUBTYPE.RUL_LPAREN))
{
//ADD_ERROR(C_IF_ERROR_MISSINGLP);
plexAnal.UnGetToken();
}
//Munch & Parse the expression.
//we got to give the expression string to the expression parser.
//
CExpParser expParser = new CExpParser();
//try
{
m_pExpression = expParser.ParseExpression(ref plexAnal, ref pSymbolTable, STMT_EXPR_TYPE.EXPR_IF);
if (m_pExpression == null)
{
//ADD_ERROR(C_IF_ERROR_MISSINGEXP);
}
}
//Munch a <)>
if ((CLexicalAnalyzer.LEX_FAIL == plexAnal.GetNextToken(ref pToken, ref pSymbolTable)) ||
pToken == null || (pToken.GetSubType() != RUL_TOKEN_SUBTYPE.RUL_RPAREN))
{
//ADD_ERROR(C_IF_ERROR_MISSINGRP);
plexAnal.UnGetToken();
}
//Eat a Statement...
CParserBuilder builder = new CParserBuilder();
m_pStatement = (CStatement)builder.CreateParser(ref plexAnal, STATEMENT_TYPE.STMT_asic);
if (null != m_pStatement)
{
int i32Ret = m_pStatement.CreateParseSubTree(ref plexAnal, ref pSymbolTable);
if (i32Ret == 0)
{
//ADD_ERROR(C_IF_ERROR_MISSINGSTMT);
}
}
else
{
//ADD_ERROR(C_IF_ERROR_MISSINGSTMT);
}
//See if you can snatch a "else"
try
{
m_pElse = (CELSEStatement)builder.CreateParser(ref plexAnal, STATEMENT_TYPE.STMT_SELECTION);
if (null != m_pElse)
{
m_pElse.CreateParseSubTree(ref plexAnal, ref pSymbolTable);
}
}
catch (Exception ex)
{
string exinfo = ex.Message;
//return 0;
}
return(1);
}
}