/// <summary>
/// Initializes reserve table with reserve words and token codes
/// </summary>
/// <returns>Reserve table with reserve words and token codes</returns>
static ReserveTable InitializeReserveWordTable()
{
ReserveTable reserveWords = new ReserveTable();
// Token Codes
reserveWords.Add("GOTO", 0);
reserveWords.Add("INTEGER", 1);
reserveWords.Add("TO", 2);
reserveWords.Add("DO", 3);
reserveWords.Add("IF", 4);
reserveWords.Add("THEN", 5);
reserveWords.Add("ELSE", 6);
reserveWords.Add("FOR", 7);
reserveWords.Add("OF", 8);
reserveWords.Add("WRITELN", 9);
reserveWords.Add("READLN", 10);
reserveWords.Add("BEGIN", 11);
reserveWords.Add("END", 12);
reserveWords.Add("VAR", 13);
reserveWords.Add("WHILE", 14);
reserveWords.Add("UNIT", 15);
reserveWords.Add("LABEL", 16);
reserveWords.Add("REPEAT", 17);
reserveWords.Add("UNTIL", 18);
reserveWords.Add("PROCEDURE", 19);
reserveWords.Add("DOWNTO", 20);
reserveWords.Add("FUNCTION", 21);
reserveWords.Add("RETURN", 22);
reserveWords.Add("REAL", 23);
reserveWords.Add("STRING", 24);
reserveWords.Add("ARRAY", 25);
// Other Tokens
reserveWords.Add("/", 30);
reserveWords.Add("*", 31);
reserveWords.Add("+", 32);
reserveWords.Add("-", 33);
reserveWords.Add("(", 34);
reserveWords.Add(")", 35);
reserveWords.Add(";", 36);
reserveWords.Add(":=", 37);
reserveWords.Add(">", 38);
reserveWords.Add("<", 39);
reserveWords.Add(">=", 40);
reserveWords.Add("<=", 41);
reserveWords.Add("=", 42);
reserveWords.Add("<>", 43);
reserveWords.Add(",", 44);
reserveWords.Add("[", 45);
reserveWords.Add("]", 46);
reserveWords.Add(":", 47);
reserveWords.Add(".", 48);
return(reserveWords);
}
/// <summary>
/// Initializes the Lexical Analyzer to a baseline state.
/// </summary>
/// <param name="fileText">The source text as a string array</param>
/// <param name="symbolTable">The table that will hold all symbols found</param>
/// <param name="reserveTable">The table containing the reserve words for the langauge</param>
public void Initialize(string[] fileText, SymbolTable symbolTable, ReserveTable reserveTable)
{
SymbolTable = symbolTable;
ReserveTable = reserveTable;
EndOfFile = false;
EchoOn = false;
FileText = fileText;
CurrentLineIndex = 0;
CurrentCharIndex = 0;
CurrentLine = FileText[CurrentLineIndex];
}
/// <summary>
/// Queries the Reserve Table to determine if the current token is a reserve word.
/// If it is then the proper token code is returned from the table.
/// If it is not a reserve word it is given the identifier token code.
/// </summary>
/// <returns></returns>
private int GetIdentifierCode()
{
int code = ReserveTable.LookupName(NextToken.ToUpper());
if (code == -1)
{
return(IDENTIFIER);
}
return(code);
}
static void Main(string[] args)
{
// My test file
//string inputFilePath = @"C:\projects\CS4100_Compiler_Design\TestInput\program.txt";
// My test file
//string inputFilePath = @"C:\projects\CS4100_Compiler_Design\TestInput\GetNextCharTest.txt";
// Provided test file
string inputFilePath = @"C:\projects\CS4100_Compiler_Design\TestInput\LexicalTestF20.txt";
// Initialize structures
ReserveTable reserveWords = InitializeReserveWordTable();
ReserveTable tokenCodes = InitializeTokenCodeTable();
SymbolTable symbolTable = new SymbolTable();
try
{
// Initialize input file
string[] fileText = InitializeInputFile(inputFilePath);
// Initialize the Lexical Analyzer (Scanner)
LexicalAnalyzer scanner = new LexicalAnalyzer();
scanner.Initialize(fileText, symbolTable, reserveWords);
bool echoOn = true;
while (!scanner.EndOfFile)
{
scanner.GetNextToken(echoOn);
if (!scanner.EndOfFile)
{
PrintToken(scanner.NextToken, scanner.TokenCode, tokenCodes, symbolTable);
}
}
symbolTable.PrintSymbolTable();
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
/// <summary>
/// Builds and prints the hard coded Reserve Table and Quad Table to run the summation algorithm.
/// </summary>
/// <returns>The Quad Table</returns>
static QuadTable BuildQuadsForSummation()
{
ReserveTable reserveTable = new ReserveTable();
reserveTable.PrintReserveTable();
QuadTable quadTable = new QuadTable(reserveTable);
quadTable.AddQuad(5, 4, 0, 0);
quadTable.AddQuad(5, 5, 0, 1);
quadTable.AddQuad(5, 5, 0, 2);
quadTable.AddQuad(3, 0, 2, 6);
quadTable.AddQuad(13, 6, 0, 8);
quadTable.AddQuad(4, 1, 2, 1);
quadTable.AddQuad(4, 2, 5, 2);
quadTable.AddQuad(14, 0, 0, 3);
quadTable.AddQuad(5, 1, 0, 3);
quadTable.AddQuad(16, 3, 0, 0);
quadTable.AddQuad(0, 0, 0, 0);
quadTable.PrintQuadTable();
return(quadTable);
}
/// <summary>
/// Prints the Lexeme, the token code, a table-looked-up 4-character mnemonic for that code,
/// and for identifiers and literals added to the symbol table, the symbol table location index of the token.
/// </summary>
/// <param name="nextToken">The token most recently found</param>
/// <param name="tokenCode">The token code of the most recently found token</param>
/// <param name="mnemonicTable">Table containing the mnemonic associated with each token code</param>
/// <param name="symbolTable">Table containing identifiers, numeric constants, and string constants</param>
static void PrintToken(string nextToken, int tokenCode, ReserveTable mnemonicTable, SymbolTable symbolTable)
{
string mneumonic = mnemonicTable.LookupCode(tokenCode);
int symbolTableIndex;
if (tokenCode == 50)
{
symbolTableIndex = symbolTable.LookupSymbol(nextToken.ToUpper());
}
else
{
symbolTableIndex = symbolTable.LookupSymbol(nextToken);
}
if (symbolTableIndex == -1)
{
Console.WriteLine($"\t|Token: {nextToken, -40} | Token Code: {tokenCode, 2} | Mneumonic: {mneumonic, 4} | Symbol Table Index: |");
}
else
{
Console.WriteLine($"\t|Token: {nextToken, -40} | Token Code: {tokenCode, 2} | Mneumonic: {mneumonic, 4} | Symbol Table Index: {symbolTableIndex, 2}|");
}
}
/// <summary>
/// Constructor which takes a Reserve Table object and initializes the Quad Table
/// </summary>
/// <param name="reserveTable"></param>
public QuadTable(ReserveTable reserveTable)
{
ReserveTable = reserveTable;
Initialize();
}
/// <summary>
/// One of the predefined one or two character tokens
/// from section 6 of the CS4100projectlangFA20-TOKENS.pdf
/// has been detected so this method stores it in NextToken.
/// </summary>
/// <param name="c">The current character</param>
private void GetOneOrTwoCharToken(char c)
{
CurrentState = State.ONE_OR_TWO_CHAR_TOKEN_ACCEPT;
switch (c)
{
case '/':
case '*':
case '+':
case '-':
case '(':
case ')':
case ';':
case '=':
case ',':
case '[':
case ']':
case '.':
NextToken += CurrentChar;
break;
case ':':
if (LookAhead() == '=')
{
NextToken += CurrentChar;
GetNextChar();
NextToken += CurrentChar;
}
else
{
NextToken += CurrentChar;
}
break;
case '>':
if (LookAhead() == '=')
{
NextToken += CurrentChar;
GetNextChar();
NextToken += CurrentChar;
}
else
{
NextToken += CurrentChar;
}
break;
case '<':
if (LookAhead() == '=' || LookAhead() == '>')
{
NextToken += CurrentChar;
GetNextChar();
NextToken += CurrentChar;
}
else
{
NextToken += CurrentChar;
}
break;
}
AcceptToken(ReserveTable.LookupName(NextToken), State.ONE_OR_TWO_CHAR_TOKEN_ACCEPT);
}
/// <summary>
/// Initializes the reserve table containing the token codes and mnemonics
/// </summary>
/// <returns>Reserve table containing the token codes and mnemonics</returns>
static ReserveTable InitializeTokenCodeTable()
{
ReserveTable tokenCodes = new ReserveTable();
// Reserve Words
tokenCodes.Add("GOTO", 0);
tokenCodes.Add("_INT", 1);
tokenCodes.Add("__TO", 2);
tokenCodes.Add("__DO", 3);
tokenCodes.Add("__IF", 4);
tokenCodes.Add("THEN", 5);
tokenCodes.Add("ELSE", 6);
tokenCodes.Add("_FOR", 7);
tokenCodes.Add("__OF", 8);
tokenCodes.Add("WTLN", 9);
tokenCodes.Add("RDLN", 10);
tokenCodes.Add("_BEG", 11);
tokenCodes.Add("_END", 12);
tokenCodes.Add("_VAR", 13);
tokenCodes.Add("WHIL", 14);
tokenCodes.Add("UNIT", 15);
tokenCodes.Add("LABL", 16);
tokenCodes.Add("REPT", 17);
tokenCodes.Add("UNTL", 18);
tokenCodes.Add("PROC", 19);
tokenCodes.Add("DOWN", 20);
tokenCodes.Add("FUNC", 21);
tokenCodes.Add("RTRN", 22);
tokenCodes.Add("REAL", 23);
tokenCodes.Add("_STR", 24);
tokenCodes.Add("ARRY", 25);
// Other Tokens
tokenCodes.Add("_DIV", 30);
tokenCodes.Add("_MUL", 31);
tokenCodes.Add("_ADD", 32);
tokenCodes.Add("_SUB", 33);
tokenCodes.Add("LPAR", 34);
tokenCodes.Add("RPAR", 35);
tokenCodes.Add("SEMI", 36);
tokenCodes.Add("ASGN", 37);
tokenCodes.Add("__GT", 38);
tokenCodes.Add("__LT", 39);
tokenCodes.Add("GTEQ", 40);
tokenCodes.Add("LTEQ", 41);
tokenCodes.Add("__EQ", 42);
tokenCodes.Add("NTEQ", 43);
tokenCodes.Add("COMM", 44);
tokenCodes.Add("LBRC", 45);
tokenCodes.Add("RBRC", 46);
tokenCodes.Add("COLN", 47);
tokenCodes.Add("_DOT", 48);
// Identifiers
tokenCodes.Add("IDNT", 50);
// Numeric Constants
tokenCodes.Add("INTC", 51);
tokenCodes.Add("FLTC", 52);
// String
tokenCodes.Add("STRC", 53);
// Used for any other input characters which are not defined.
tokenCodes.Add("UNDF", 99);
return(tokenCodes);
}