public Token.Token NextToken()
{
SkipWhiteSpace();
if (EndOfSource())
{
return null;
}
if ("{}}[]:,".Contains(lookahead))
{
Token.Token ret = new Token.Token(Token.TokenType.SYMBOL, lookahead.ToString());
Advance();
return ret;
}
else if (lookahead == '"')
{
return String();
}
else if (Char.IsDigit(lookahead))
{
return Number();
}
else
{
return Word();
}
}
private Token.Token String()
{
String val = "";
char prev = lookahead;
while (true)
{
Advance();
if (prev == '\\')
{
switch (lookahead)
{
case 'n':
val += '\n';
break;
case 'r':
val += '\r';
break;
case '\\':
val += '\\';
break;
case '"':
val += '"';
break;
default:
throw new InvalidLexemeException("Invalid escape sequence \\" + lookahead);
}
}
else
{
if (lookahead == '"')
{
Token.Token ret = new Token.Token(Token.TokenType.STRING, val);
Advance();
return ret;
}
val += lookahead;
}
prev = lookahead;
}
}
private void Advance()
{
currentToken = lexer.NextToken();
}
