/*
* Parses TYPEDEF commands (First token, then delegates rest to specific TYPEDEF implementations).
* Populates typedef table.
*/
public static TYPEDEF Parse(string code, Dictionary <string, TYPEDEF> typedefTable)
{
if (String.IsNullOrEmpty(code))
{
throw new ArgumentNullException("code");
}
if (null == typedefTable)
{
throw new ArgumentNullException("typedefTable");
}
string[] tokens = code.Split(new char[] { ' ', '\t' }, StringSplitOptions.RemoveEmptyEntries);
if (tokens.Length < 3)
{
throw new ArgumentException("TYPEDEF statements must consist of at least three tokens (TYPEDEF <NAME> <TYPE>), received: " + code);
}
if (tokens[0].ToUpper() != "TYPEDEF")
{
throw new ArgumentException("TYPEDEFs must start with keyword TYPEDEF, but received: " + tokens[0]);
}
TYPEDEF parsedType = null;
string Type = tokens[2].ToUpper();
if (Type == "BASIC")
{
parsedType = new BASIC(tokens, typedefTable);
}
else if (Type == "PRODUCT")
{
parsedType = new PRODUCT(tokens, typedefTable);
}
else if (Type == "SUM")
{
parsedType = new SUM(tokens, typedefTable);
}
else if (Type == "SEQUENCE")
{
parsedType = new SEQUENCE(tokens, typedefTable);
}
else if (Type == "FUNCTION")
{
parsedType = new FUNCTION(tokens, typedefTable);
}
else if (Type == "SUBTYPE")
{
parsedType = new SUBTYPE(tokens, typedefTable);
}
else
{
throw new SyntacticException("Not a valid TYPEDEF: " + code);
}
return(parsedType);
}
public override string Eval(List <Expression> expList, Dictionary <string, TYPEDEF> typedefTable, Dictionary <string, VARDECL> symbolTable)
{
if (expList.Count != 2)
{
throw new SemanticException("CONS Operator requires one expression (CONS <exp1> <exp2> ).");
}
string seqname1 = expList[0].Eval(typedefTable, symbolTable);
string seqname2 = expList[1].Eval(typedefTable, symbolTable);
if (!typedefTable.ContainsKey(seqname1))
{
throw new SemanticException("There is no SEQUENCE type named " + seqname1);
}
if (!typedefTable.ContainsKey(seqname2))
{
throw new SemanticException("There is no SEQUENCE type named " + seqname2);
}
TYPEDEF seqdef1 = typedefTable[seqname1];
TYPEDEF seqdef2 = typedefTable[seqname2];
if (seqdef1.Type != "SEQUENCE")
{
throw new SemanticException("CONS operator is only allowed on two SEQUENCEs");
}
if (seqdef2.Type != "SEQUENCE")
{
throw new SemanticException("CONS operator is only allowed on two SEQUENCEs");
}
if ((seqdef1 as SEQUENCE).AliasedType != (seqdef2 as SEQUENCE).AliasedType)
{
throw new SemanticException("Type Error: Can not CONS two different types together.");
}
return((seqdef1 as SEQUENCE).Name);
}
public override string Eval(List <Expression> expList, Dictionary <string, TYPEDEF> typedefTable, Dictionary <string, VARDECL> symbolTable)
{
if (expList.Count < 1)
{
throw new SemanticException("NIL Operator requires one expression (NIL <exp1> <exp2> ).");
}
string seqname1 = expList[0].Variable;
if (!typedefTable.ContainsKey(seqname1))
{
throw new SemanticException("There is no SEQUENCE type named " + seqname1);
}
TYPEDEF seqdef1 = typedefTable[seqname1];
if (seqdef1.Type != "SEQUENCE")
{
throw new SemanticException("NIL operator is only allowed on two SEQUENCEs");
}
return((seqdef1 as SEQUENCE).Name);
}
public override string Eval(Dictionary <string, TYPEDEF> typedefTable, Dictionary <string, VARDECL> symbolTable)
{
TYPEDEF type = typedefTable[symbolTable[(expList[0] as VariableExpression).Variable].Type];
return(type.Eval(expList.GetRange(1, expList.Count - 1), typedefTable, symbolTable));
}
public static void Main(string[] args)
{
if (args.Length < 1 || !File.Exists(args[0]))
{
Console.WriteLine("tail.exe file.tail");
System.Environment.Exit(0);
}
Dictionary <string, TYPEDEF> typedefTable = new Dictionary <string, TYPEDEF> ();
Dictionary <string, VARDECL> symbolTable = new Dictionary <string, VARDECL> ();
string[] lines = File.ReadAllLines(args[0]);
// Organize the TAIL contructs into lists.
// Then process the lists.
// I assume that if correct syntax is used and that
// only TAIL expressions, typedefs, vardecls or empty lines
// can exist in a tail file.
int lineCount = 0;
foreach (string line in lines)
{
try
{
if (line.ToUpper().StartsWith("TYPEDEF"))
{
TYPEDEF.Parse(line, typedefTable);
}
else if (line.ToUpper().StartsWith("VARDECL"))
{
new VARDECL(line, typedefTable, symbolTable);
}
else if (!String.IsNullOrEmpty(line))
{
ExpressionEval.Eval(line, typedefTable, symbolTable);
}
}
catch (SemanticException semex)
{
Console.WriteLine("Semantic Exception on line " + lineCount + " : " + semex.Message);
}
catch (SyntacticException synex)
{
Console.WriteLine("Syntax Exceptionon line " + lineCount + " : " + synex.Message);
}
catch (Exception ex)
{
Console.WriteLine("Internal Exception: " + ex.Message);
}
lineCount++;
}
/*
* foreach (string str in typedefTable.Keys)
* {
* Console.WriteLine("Type: " + str);
* }
*
* Console.WriteLine("");
*
* foreach (string str in symbolTable.Keys)
* {
* Console.WriteLine("Var: " + str);
* }*/
}