crazy4s
asked on
Error in c# Visual Studio
Hi all,
I'm a newbie in using c#. I got 2 errors when i debug the below program, can anyone help me to figure out where's wrong?
Thanks in advance.
Error:
An unhandled exception of type 'System.OverflowException'
Additional information: Value was either too large or too small for a character.
I'm a newbie in using c#. I got 2 errors when i debug the below program, can anyone help me to figure out where's wrong?
Thanks in advance.
Error:
An unhandled exception of type 'System.OverflowException'
Additional information: Value was either too large or too small for a character.
using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Clist_Parser
{
class Lexer
{
private char ch = ' ';
private StreamReader input;
private int lineno = 1;
private int col = 1;
private const string letters = "abcdefghijklmnopqrstuvwxyz"
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
private const string digits = "0123456789";
private const char eolnCh = '\n';
// private const char eofCh = '\0';
private int nextChar()
{
int nextchar;
nextchar = input.Read();
return nextchar;
}
public int get_lineno()
{
return lineno;
}
private bool isLetter(char c)
{
return (c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z');
}
private bool isDigit(char c)
{
return (c >= '0' && c <= '9');
}
private void check(char c)
{
ch = Convert.ToChar(nextChar());
if (ch != c)
error("Illegal character, expecting " + c);
ch = Convert.ToChar(nextChar());
}
private Token chkOpt(char c, Token one, Token two)
{
ch = Convert.ToChar(nextChar());
if (ch != '=')
return one;
else
return two;
}
private String concat(String set)
{
String r = "";
do
{
r += ch;
ch = Convert.ToChar(nextChar());
} while (set.IndexOf(ch) >= 0);
return r;
}
public int getCurrentLine()
{
return lineno;
}
public void error(String msg)
{
Console.WriteLine(lineno);
Console.WriteLine(" Error: column " + col + " " + msg);
return;
}
/*
* param: filename is the file you need to open
* set up the member ch which is the next char in
* the file to be analyzed
*/
public Lexer(String fileName)
{
try
{
input = new StreamReader(fileName);
ch = Convert.ToChar(nextChar());
}
catch (FileNotFoundException e)
{
// Let the user know what went wrong.
Console.WriteLine(e.Message);
}
}
/*
* This method tokenize the input stream from the input;
* return each token to the caller.
*
*/
public Token next()
{
do
{
if (isLetter(ch))
{
String spelling = concat(letters + digits);
return Token.keyword(spelling);
}
else if (isDigit(ch))
{
String number = concat(digits);
if (ch != '.')
return Token.mkIntLiteral(number);
number += concat(digits);
return Token.mkIntLiteral(number);
}
else switch (ch)
{
case ' ': case '\t': case '\r': case eolnCh:
ch = Convert.ToChar(nextChar());
break;
case '/':
ch = Convert.ToChar(nextChar());
if (ch != '/')
return Token.divideTok;
do
{
ch = Convert.ToChar(nextChar());
} while (ch != eolnCh);
ch = Convert.ToChar(nextChar());
break;
case '\'':
char ch1 = Convert.ToChar(nextChar());
nextChar();
ch = Convert.ToChar(nextChar());
return Token.mkCharLiteral("" + ch1);
case '+':
ch = Convert.ToChar(nextChar());
return Token.plusTok;
case '-':
ch = Convert.ToChar(nextChar());
return Token.minusTok;
case '*':
ch = Convert.ToChar(nextChar());
return Token.multiplyTok;
case '!':
chkOpt('!', Token.notTok, Token.noteqTok);
break;
case '>':
chkOpt('>', Token.gtTok, Token.gteqTok);
break;
case '<':
chkOpt('<', Token.ltTok, Token.lteqTok);
break;
case ',':
ch = Convert.ToChar(nextChar());
return Token.commaTok;
case ';':
ch = Convert.ToChar(nextChar());
return Token.semicolonTok;
case '(':
ch = Convert.ToChar(nextChar());
return Token.leftParenTok;
case ')':
ch = Convert.ToChar(nextChar());
return Token.rightParenTok;
case '[':
ch = Convert.ToChar(nextChar());
return Token.leftBracketTok;
case ']':
ch = Convert.ToChar(nextChar());
return Token.rightBracketTok;
case '{':
ch = Convert.ToChar(nextChar());
return Token.leftBraceTok;
case '}':
ch = Convert.ToChar(nextChar());
return Token.rightBraceTok;
/* case "while":
ch = Convert.ToChar(nextChar());
return Token.whileTok;
case "true":
ch = Convert.ToChar(nextChar());
return Token.trueTok;
case "main":
ch = Convert.ToChar(nextChar());
return Token.mainTok;
case "int":
ch = Convert.ToChar(nextChar());
return Token.intTok;
case "if":
ch = Convert.ToChar(nextChar());
return Token.ifTok;
case "float":
ch = Convert.ToChar(nextChar());
return Token.floatTok;
case "false":
ch = Convert.ToChar(nextChar());
return Token.falseTok;
case "else":
ch = Convert.ToChar(nextChar());
return Token.elseTok;
case "char":
ch = Convert.ToChar(nextChar());
return Token.charTok;
case "bool":
ch = Convert.ToChar(nextChar());
return Token.boolTok;
case "eof":
ch = Convert.ToChar(nextChar());
return Token.eofTok; */
case '&':
check('&');
return Token.andTok;
case '|':
check('|');
return Token.orTok;
case '=':
chkOpt('=', Token.assignTok, Token.eqeqTok);
break;
} // end switch
} while (true);
} // next
}
}
debug and use stack trace to find the error location in your code
ASKER
I have this token file....
the program actually executed with no errors... but when i debug the console disappeared within a sec and the msg box(the error) pop up!
this is the main program
the program actually executed with no errors... but when i debug the console disappeared within a sec and the msg box(the error) pop up!
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Clist_Parser
{
class Token
{
public enum TokenType
{
Bool, Char, Else, False, Float,
If, Int, Main, True, While,
Eof, LeftBrace, RightBrace, LeftBracket, RightBracket,
LeftParen, RightParen, Semicolon, Comma, Assign,
Equals, Less, LessEqual, Greater, GreaterEqual,
Not, NotEqual, Plus, Minus, Multiply,
Divide, And, Or, Identifier, IntLiteral,
FloatLiteral, CharLiteral
}
private static readonly int KEYWORDS = 10;
private static readonly String[] reserved = new String[KEYWORDS];
private static Token[] token = new Token[KEYWORDS];
public static readonly Token eofTok = new Token(TokenType.Eof, "<<EOF>>");
public static readonly Token boolTok = new Token(TokenType.Bool, "bool");
public static readonly Token charTok = new Token(TokenType.Char, "char");
public static readonly Token elseTok = new Token(TokenType.Else, "else");
public static readonly Token falseTok = new Token(TokenType.False, "false");
public static readonly Token floatTok = new Token(TokenType.Float, "float");
public static readonly Token ifTok = new Token(TokenType.If, "if");
public static readonly Token intTok = new Token(TokenType.Int, "int");
public static readonly Token mainTok = new Token(TokenType.Main, "main");
public static readonly Token trueTok = new Token(TokenType.True, "true");
public static readonly Token whileTok = new Token(TokenType.While, "while");
public static readonly Token leftBraceTok = new Token(TokenType.LeftBrace, "{");
public static readonly Token rightBraceTok = new Token(TokenType.RightBrace, "}");
public static readonly Token leftBracketTok = new Token(TokenType.LeftBracket, "[");
public static readonly Token rightBracketTok = new Token(TokenType.RightBracket, "]");
public static readonly Token leftParenTok = new Token(TokenType.LeftParen, "(");
public static readonly Token rightParenTok = new Token(TokenType.RightParen, ")");
public static readonly Token semicolonTok = new Token(TokenType.Semicolon, ";");
public static readonly Token commaTok = new Token(TokenType.Comma, ",");
public static readonly Token assignTok = new Token(TokenType.Assign, "=");
public static readonly Token eqeqTok = new Token(TokenType.Equals, "==");
public static readonly Token ltTok = new Token(TokenType.Less, "<");
public static readonly Token lteqTok = new Token(TokenType.LessEqual, "<=");
public static readonly Token gtTok = new Token(TokenType.Greater, ">");
public static readonly Token gteqTok = new Token(TokenType.GreaterEqual, ">=");
public static readonly Token notTok = new Token(TokenType.Not, "!");
public static readonly Token noteqTok = new Token(TokenType.NotEqual, "!=");
public static readonly Token plusTok = new Token(TokenType.Plus, "+");
public static readonly Token minusTok = new Token(TokenType.Minus, "-");
public static readonly Token multiplyTok = new Token(TokenType.Multiply, "*");
public static readonly Token divideTok = new Token(TokenType.Divide, "/");
public static readonly Token andTok = new Token(TokenType.And, "&&");
public static readonly Token orTok = new Token(TokenType.Or, "||");
private TokenType type;
private String value = "";
private Token(TokenType t, String v)
{
type = t;
value = v;
if (t.CompareTo(TokenType.Eof) < 0)
{
int ti = (int)t;
reserved[ti] = v;
token[ti] = this;
}
}
public TokenType getType() { return type; }
public String getValue() { return value; }
public static Token keyword(String name)
{
char ch = name[0];
if (ch >= 'A' && ch <= 'Z') return mkIdentTok(name);
for (int i = 0; i < KEYWORDS; i++)
if (name.CompareTo(reserved[i]) == 0) return token[i];
return mkIdentTok(name);
} // keyword
public static Token mkIdentTok(String name)
{
return new Token(TokenType.Identifier, name);
}
public static Token mkIntLiteral(String name)
{
return new Token(TokenType.IntLiteral, name);
}
public static Token mkFloatLiteral(String name)
{
return new Token(TokenType.FloatLiteral, name);
}
public static Token mkCharLiteral(String name)
{
return new Token(TokenType.CharLiteral, name);
}
public String toString()
{
if (type.CompareTo(TokenType.Identifier) < 0) return value;
return type + "\t" + value;
} // toString
}
}this is the main program
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Clist_Parser
{
class Program
{
static void Main(string[] args)
{
Lexer lexer = new Lexer(args[0]);
Token tok = lexer.next();
while (tok != Token.eofTok)
{
Console.WriteLine("Line " + lexer.getCurrentLine() + "Token Type is " + tok.getType() + " string value is " + tok.getValue());
tok = lexer.next();
}
}
}
}
see this: http://msdn.microsoft.com/en-us/library/system.console.read.aspx
i guess that your error is around the nextchar = input.Read();
when it return -1 then you have problem during converting -1 to char.
i guess that your error is around the nextchar = input.Read();
when it return -1 then you have problem during converting -1 to char.
ASKER
but why is it returning -1?
it should be reading the first character in the file ryte? how can i solve this prob?
it should be reading the first character in the file ryte? how can i solve this prob?
ASKER CERTIFIED SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
do you meant something like this:
private int result = 1;
public Lexer(String fileName)
{
try
{
input = new StreamReader(fileName);
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
}
catch (FileNotFoundException e)
{
// Let the user know what went wrong.
Console.WriteLine(e.Message);
}
}
yes, st. like this
ASKER
hmm but i still get the same error msg box pop up?
do i still need to do anything with it?
do i still need to do anything with it?
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
sorry can you explain in more details... n do i need to check for those in the func next() too or?
everywhere, to make sure that you do not pass -1 to the function that convert number to char.
Try it, if not , just share your current code and a sample test file, i will try to debug this
Try it, if not , just share your current code and a sample test file, i will try to debug this
ASKER
looks abit messy but i tried checking it all... but still got the same error msg...
using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Clist_Parser
{
class Lexer
{
private char ch = ' ';
private char ch1;
private StreamReader input;
private int lineno = 1;
private int col = 1;
private int result = 1;
private const string letters = "abcdefghijklmnopqrstuvwxyz"
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
private const string digits = "0123456789";
private const char eolnCh = '\n';
// private const char eofCh = '\0';
private int nextChar()
{
int nextchar;
nextchar = input.Read();
return nextchar;
}
public int get_lineno()
{
return lineno;
}
private bool isLetter(char c)
{
return (c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z');
}
private bool isDigit(char c)
{
return (c >= '0' && c <= '9');
}
private void check(char c)
{
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
if (ch != c)
error("Illegal character, expecting " + c);
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
}
private Token chkOpt(char c, Token one, Token two)
{
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
if (ch != '=')
return one;
else
return two;
}
private String concat(String set)
{
String r = "";
do
{
r += ch;
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
} while (set.IndexOf(ch) >= 0);
return r;
}
public int getCurrentLine()
{
return lineno;
}
public void error(String msg)
{
Console.WriteLine(lineno);
Console.WriteLine(" Error: column " + col + " " + msg);
return;
}
/*
* param: filename is the file you need to open
* Also, you need to set up the member ch which is the next char in
* the file to be analyzed
*/
public Lexer(String fileName)
{
try
{
input = new StreamReader(fileName);
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
}
catch (FileNotFoundException e)
{
// Let the user know what went wrong.
Console.WriteLine(e.Message);
}
}
/*
* This method tokenize the input stream from the input;
* return each token to the caller.
*
*/
public Token next()
{
do
{
if (isLetter(ch))
{
String spelling = concat(letters + digits);
return Token.keyword(spelling);
}
else if (isDigit(ch))
{
String number = concat(digits);
if (ch != '.')
return Token.mkIntLiteral(number);
number += concat(digits);
return Token.mkIntLiteral(number);
}
else switch (ch)
{
case ' ': case '\t': case '\r': case eolnCh:
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
break;
case '/':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
if (ch != '/')
return Token.divideTok;
do
{
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
} while (ch != eolnCh);
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
break;
case '\'':
while (result != -1)
{
ch1 = Convert.ToChar(nextChar());
result++;
}
nextChar();
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.mkCharLiteral("" + ch1);
case '+':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.plusTok;
case '-':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.minusTok;
case '*':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.multiplyTok;
case '!':
chkOpt('!', Token.notTok, Token.noteqTok);
break;
case '>':
chkOpt('>', Token.gtTok, Token.gteqTok);
break;
case '<':
chkOpt('<', Token.ltTok, Token.lteqTok);
break;
case ',':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.commaTok;
case ';':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.semicolonTok;
case '(':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.leftParenTok;
case ')':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.rightParenTok;
case '[':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.leftBracketTok;
case ']':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.rightBracketTok;
case '{':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.leftBraceTok;
case '}':
while (result != -1)
{
ch = Convert.ToChar(nextChar());
result++;
}
return Token.rightBraceTok;
/* case "while":
ch = Convert.ToChar(nextChar());
return Token.whileTok;
case "true":
ch = Convert.ToChar(nextChar());
return Token.trueTok;
case "main":
ch = Convert.ToChar(nextChar());
return Token.mainTok;
case "int":
ch = Convert.ToChar(nextChar());
return Token.intTok;
case "if":
ch = Convert.ToChar(nextChar());
return Token.ifTok;
case "float":
ch = Convert.ToChar(nextChar());
return Token.floatTok;
case "false":
ch = Convert.ToChar(nextChar());
return Token.falseTok;
case "else":
ch = Convert.ToChar(nextChar());
return Token.elseTok;
case "char":
ch = Convert.ToChar(nextChar());
return Token.charTok;
case "bool":
ch = Convert.ToChar(nextChar());
return Token.boolTok;
case "eof":
ch = Convert.ToChar(nextChar());
return Token.eofTok; */
case '&':
check('&');
return Token.andTok;
case '|':
check('|');
return Token.orTok;
case '=':
chkOpt('=', Token.assignTok, Token.eqeqTok);
break;
} // end switch
} while (true);
} // next
}
}the filename to read - test2.txt
// a first program with
// two comment lins
int main () {
char c ;
int i;
c = 'h';
} // end of file
ok,
it is really like i think.
And here is a example how to fix
int tmp= nextChar();
while (tmp != -1)
{
ch = Convert.ToChar(tmp);
tmp = nextChar();
result++;
}
it is really like i think.
And here is a example how to fix
int tmp= nextChar();
while (tmp != -1)
{
ch = Convert.ToChar(tmp);
tmp = nextChar();
result++;
}
ASKER
hmm is your result same as col since i've this at the beginning?
private int col = 1;
but i got no output for this:(
private int col = 1;
but i got no output for this:(
public Lexer(String fileName)
{
try
{
input = new StreamReader(fileName);
int tmp = nextChar();
while (tmp != -1)
{
ch = Convert.ToChar(tmp);
tmp = nextChar();
col++;
}
}
catch (FileNotFoundException e)
{
// Let the user know what went wrong.
Console.WriteLine(e.Message);
}
}
public Token next()
{
int tmp;
do
{
if (isLetter(ch))
{
String spelling = concat(letters + digits);
return Token.keyword(spelling);
}
else if (isDigit(ch))
{
String number = concat(digits);
if (ch != '.')
return Token.mkIntLiteral(number);
number += concat(digits);
return Token.mkIntLiteral(number);
}
else switch (ch)
{
case ' ': case '\t': case '\r': case eolnCh:
tmp = nextChar();
while (tmp != -1)
{
ch = Convert.ToChar(tmp);
tmp = nextChar();
col++;
}
break;
case '/':
ch = Convert.ToChar(nextChar());
if (ch != '/')
return Token.divideTok;
string line = input.ReadLine();
string comment = line.Substring(col);
Console.WriteLine("Line " + getCurrentLine() + "Token Type is COMMENT and value is /" + comment);
do
{
tmp = nextChar();
while (tmp != -1)
{
ch = Convert.ToChar(tmp);
tmp = nextChar();
col++;
}
} while (ch != eolnCh);
tmp = nextChar();
while (tmp != -1)
{
ch = Convert.ToChar(tmp);
tmp = nextChar();
col++;
}
break;
// other codes
you must use it appropriately:
use while () , if (), .... as necessary
use while () , if (), .... as necessary
ASKER
i edited some of the codes... but i'm not sure how can i check for next char after the '=' by not changing the chkOpt method....
i only call nextChar() once since i want to check every single char once only...
But i got a really weird output for this test:
// a first program with
// two comment lins
int main () {
char c ;
int i;
c = 'h';
} // end of file
i only call nextChar() once since i want to check every single char once only...
But i got a really weird output for this test:
// a first program with
// two comment lins
int main () {
char c ;
int i;
c = 'h';
} // end of file
using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Clist_Parser
{
class Lexer
{
private char ch;
private StreamReader input;
private int lineno = 1;
private int col = 1;
private const string letters = "abcdefghijklmnopqrstuvwxyz"
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
private const string digits = "0123456789";
private const char eolnCh = '\n';
// private const char eofCh = '\0';
private int nextChar()
{
int nextchar;
nextchar = input.Read();
return nextchar;
}
public int get_lineno()
{
return lineno;
}
private bool isLetter(char c)
{
return (c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z');
}
private bool isDigit(char c)
{
return (c >= '0' && c <= '9');
}
private void check(char c)
{
ch = Convert.ToChar(nextChar());
if (ch != c)
error("Illegal character, expecting " + c);
ch = Convert.ToChar(nextChar());
}
private Token chkOpt(char c, Token one, Token two)
{
ch = Convert.ToChar(nextChar());
if (ch != '=')
return one;
else
return two;
}
private String concat(String set)
{
String r = "";
do
{
r += ch;
ch = Convert.ToChar(nextChar());
} while (set.IndexOf(ch) >= 0);
return r;
}
public int getCurrentLine()
{
return lineno;
}
public void error(String msg)
{
Console.WriteLine(lineno);
Console.WriteLine(" Error: column " + col + " " + msg);
return;
}
/*
* param: filename is the file you need to open
* set up the member ch which is the next char in
* the file to be analyzed
*/
public Lexer(String fileName)
{
try
{
input = new StreamReader(fileName);
int tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
}
}
catch (FileNotFoundException e)
{
// Let the user know what went wrong.
Console.WriteLine(e.Message);
}
}
/*
* This method tokenize the input stream from the input;
* return each token to the caller.
*
*/
public Token next()
{
int tmp;
do
{
if (isLetter(ch))
{
String spelling = concat(letters + digits);
return Token.keyword(spelling);
}
else if (isDigit(ch))
{
String number = concat(digits);
if (ch != '.')
return Token.mkIntLiteral(number);
number += concat(digits);
return Token.mkIntLiteral(number);
}
else switch (ch)
{
case ' ': case '\t': case '\r':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
tmp = nextChar();
col++;
}
break;
case eolnCh:
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
tmp = nextChar();
col = 1;
lineno++;
}
break;
case '/':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
if (ch != '/')
return Token.divideTok;
string line = input.ReadLine();
string comment = line.Substring(0);
Console.WriteLine("Line " + getCurrentLine() + "Token Type is COMMENT and value is //" + comment);
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col = 1;
lineno++;
}
break;
case '\'':
char ch1 = ' ';
tmp = nextChar();
if (tmp != -1)
{
ch1 = Convert.ToChar(tmp);
tmp = nextChar();
col++;
}
nextChar();
tmp = nextChar();
if (tmp != -1)
{
ch1 = Convert.ToChar(tmp);
tmp = nextChar();
col++;
}
return Token.mkCharLiteral("" + ch1);
case '+':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.plusTok;
case '-':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.minusTok;
case '*':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.multiplyTok;
case '!':
return chkOpt('!', Token.notTok, Token.noteqTok);
case '>':
return chkOpt('>', Token.gtTok, Token.gteqTok);
case '<':
return chkOpt('<', Token.ltTok, Token.lteqTok);
case ',':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.commaTok;
case ';':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.semicolonTok;
case '(':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.leftParenTok;
case ')':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.rightParenTok;
case '[':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.leftBracketTok;
case ']':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.rightBracketTok;
case '{':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.leftBraceTok;
case '}':
tmp = nextChar();
if (tmp != -1)
{
ch = Convert.ToChar(tmp);
col++;
}
return Token.rightBraceTok;
/* case "while":
ch = Convert.ToChar(nextChar());
return Token.whileTok;
case "true":
ch = Convert.ToChar(nextChar());
return Token.trueTok;
case "main":
ch = Convert.ToChar(nextChar());
return Token.mainTok;
case "int":
ch = Convert.ToChar(nextChar());
return Token.intTok;
case "if":
ch = Convert.ToChar(nextChar());
return Token.ifTok;
case "float":
ch = Convert.ToChar(nextChar());
return Token.floatTok;
case "false":
ch = Convert.ToChar(nextChar());
return Token.falseTok;
case "else":
ch = Convert.ToChar(nextChar());
return Token.elseTok;
case "char":
ch = Convert.ToChar(nextChar());
return Token.charTok;
case "bool":
ch = Convert.ToChar(nextChar());
return Token.boolTok;
case "eof":
ch = Convert.ToChar(nextChar());
return Token.eofTok; */
case '&':
check('&');
return Token.andTok;
case '|':
check('|');
return Token.orTok;
case '=':
return chkOpt('=', Token.assignTok, Token.eqeqTok);
} // end switch
} while (true);
} // next
}
}ASKER
since i solved the errors i should proceed to another thread to ask another question.
Thanks.
Thanks.
What is token ?
Do you try to assign a string to a char somewhere ?