/// <summary>
/// <Factor>::= <number> | ( <expr> ) | {+|-} <factor>
/// <variable> | TRUE | FALSE
/// </summary>
public Exp Factor(ProcedureBuilder ctx)
{
TOKEN l_token;
Exp RetValue = null;
if (Current_Token == TOKEN.TOK_NUMERIC)
{
RetValue = new NumericConstant(GetNumber());
Current_Token = GetToken();
}
else if (Current_Token == TOKEN.TOK_STRING)
{
RetValue = new StringLiteral(last_str);
Current_Token = GetToken();
}
else if (Current_Token == TOKEN.TOK_BOOL_FALSE ||
Current_Token == TOKEN.TOK_BOOL_TRUE)
{
RetValue = new BooleanConstant(
Current_Token == TOKEN.TOK_BOOL_TRUE ? true : false);
Current_Token = GetToken();
}
else if (Current_Token == TOKEN.TOK_OPAREN)
{
Current_Token = GetToken();
RetValue = BExpr(ctx); // Recurse
if (Current_Token != TOKEN.TOK_CPAREN)
{
Console.WriteLine("Missing Closing Parenthesis\n");
throw new Exception();
}
Current_Token = GetToken();
}
else if (Current_Token == TOKEN.TOK_PLUS || Current_Token == TOKEN.TOK_SUB)
{
l_token = Current_Token;
Current_Token = GetToken();
RetValue = Factor(ctx);
if (l_token == TOKEN.TOK_PLUS)
{
RetValue = new UnaryPlus(RetValue);
}
else
{
RetValue = new UnaryMinus(RetValue);
}
}
else if (Current_Token == TOKEN.TOK_NOT)
{
l_token = Current_Token;
Current_Token = GetToken();
RetValue = Factor(ctx);
RetValue = new LogicalNot(RetValue);
}
else if (Current_Token == TOKEN.TOK_UNQUOTED_STRING)
{
String str = base.last_str;
if (!prog.IsFunction(str))
{
//
// if it is not a function..it ought to
// be a variable...
SYMBOL_INFO inf = ctx.GetSymbol(str);
if (inf == null)
{
throw new Exception("Undefined symbol");
}
GetNext();
return(new Variable(inf));
}
//
// P can be null , if we are parsing a
// recursive function call
//
Procedure p = prog.GetProc(str);
// It is a Function Call
// Parse the function invocation
//
Exp ptr = ParseCallProc(ctx, p);
GetNext();
return(ptr);
}
else
{
Console.WriteLine("Illegal Token");
throw new Exception();
}
return(RetValue);
}
/// <summary>
/// <Factor>::= <number> | ( <expr> ) | {+|-} <factor>
/// <variable> | TRUE | FALSE
/// </summary>
public Exp Factor(ProcedureBuilder ctx)
{
TOKEN l_token;
Exp RetValue = null;
if (Current_Token == TOKEN.TOK_NUMERIC)
{
RetValue = new NumericConstant(GetNumber());
Current_Token = GetToken();
}
else if (Current_Token == TOKEN.TOK_STRING)
{
RetValue = new StringLiteral(last_str);
Current_Token = GetToken();
}
else if (Current_Token == TOKEN.TOK_BOOL_FALSE ||
Current_Token == TOKEN.TOK_BOOL_TRUE)
{
RetValue = new BooleanConstant(
Current_Token == TOKEN.TOK_BOOL_TRUE ? true : false);
Current_Token = GetToken();
}
else if (Current_Token == TOKEN.TOK_OPAREN)
{
Current_Token = GetToken();
RetValue = BExpr(ctx); // Recurse
if (Current_Token != TOKEN.TOK_CPAREN)
{
Console.WriteLine("Missing Closing Parenthesis\n");
throw new CParserException(-100, "Missing Closing Parenthesis\n", SaveIndex());
}
Current_Token = GetToken();
}
else if (Current_Token == TOKEN.TOK_PLUS || Current_Token == TOKEN.TOK_SUB)
{
l_token = Current_Token;
Current_Token = GetToken();
RetValue = Factor(ctx);
if (l_token == TOKEN.TOK_PLUS)
{
RetValue = new UnaryPlus(RetValue);
}
else
{
RetValue = new UnaryMinus(RetValue);
}
}
else if (Current_Token == TOKEN.TOK_NOT)
{
l_token = Current_Token;
Current_Token = GetToken();
RetValue = Factor(ctx);
RetValue = new LogicalNot(RetValue);
}
else if (Current_Token == TOKEN.TOK_UNQUOTED_STRING)
{
String str = base.last_str;
if (!prog.IsFunction(str))
{
//
// if it is not a function..it ought to
// be a variable...
SYMBOL_INFO inf = ctx.GetSymbol(str);
if (inf == null)
{
throw new CParserException(-100, "Undefined symbol " + str, SaveIndex());
}
if (inf.Type != TYPE_INFO.TYPE_ARRAY &&
inf.Type != TYPE_INFO.TYPE_MAP)
{
GetNext();
return(new Variable(inf));
}
if (inf.Type == TYPE_INFO.TYPE_ARRAY)
{
GetNext();
if (Current_Token != TOKEN.TOK_OSUBSCRIPT)
{
CSyntaxErrorLog.AddLine("[ expected");
CSyntaxErrorLog.AddLine(GetCurrentLine(SaveIndex()));
throw new CParserException(-100, "[ expected", SaveIndex());
}
GetNext();
Exp index = BExpr(ctx);
if (Current_Token != TOKEN.TOK_CSUBSCRIPT)
{
CSyntaxErrorLog.AddLine("] expected");
CSyntaxErrorLog.AddLine(GetCurrentLine(SaveIndex()));
throw new CParserException(-100, "] expected", SaveIndex());
}
GetNext();
return(new IndexedExp(new IndexedVariable(inf, index, null)));
}
else
{
GetNext();
if (Current_Token != TOKEN.TOK_OSUBSCRIPT)
{
CSyntaxErrorLog.AddLine("[ expected");
CSyntaxErrorLog.AddLine(GetCurrentLine(SaveIndex()));
throw new CParserException(-100, "[ expected", SaveIndex());
}
GetNext();
Exp index = BExpr(ctx);
if (Current_Token != TOKEN.TOK_CSUBSCRIPT)
{
CSyntaxErrorLog.AddLine("] expected");
CSyntaxErrorLog.AddLine(GetCurrentLine(SaveIndex()));
throw new CParserException(-100, "] expected", SaveIndex());
}
GetNext();
return(new HashExp(new HashedVariable(inf, index, null)));
}
}
//
// P can be null , if we are parsing a
// recursive function call
//
Procedure p = prog.GetProc(str);
// It is a Function Call
// Parse the function invocation
//
Exp ptr = ParseCallProc(ctx, p);
GetNext();
return(ptr);
}
else
{
//Console.WriteLine("Illegal Token");
throw new CParserException(-100, "Illegal Token", SaveIndex());
}
return(RetValue);
}