public static StringBuilder ExtractOperator(this StringBuilder @this)
{
return(@this.ExtractOperator(0));
}
public static StringBuilder ExtractOperator(this StringBuilder @this, out int endIndex)
{
return(@this.ExtractOperator(0, out endIndex));
}
public static StringBuilder ExtractOperator(this StringBuilder @this, int startIndex)
{
int endIndex;
return(@this.ExtractOperator(startIndex, out endIndex));
}
public static StringBuilder ExtractToken(this StringBuilder @this, int startIndex, out int endIndex)
{
/* A token can be:
* - Keyword / Literal
* - Operator
* - String
* - Integer
* - Real
*/
// CHECK first which type is the token
var ch1 = @this[startIndex];
var pos = startIndex + 1;
switch (ch1)
{
case '@':
if (pos < @this.Length && @this[pos] == '"')
{
return(@this.ExtractStringArobasDoubleQuote(startIndex, out endIndex));
}
if (pos < @this.Length && @this[pos] == '\'')
{
return(@this.ExtractStringArobasSingleQuote(startIndex, out endIndex));
}
break;
case '"':
return(@this.ExtractStringDoubleQuote(startIndex, out endIndex));
case '\'':
return(@this.ExtractStringSingleQuote(startIndex, out endIndex));
case '`':
case '~':
case '!':
case '#':
case '$':
case '%':
case '^':
case '&':
case '*':
case '(':
case ')':
case '-':
case '_':
case '=':
case '+':
case '[':
case ']':
case '{':
case '}':
case '|':
case ':':
case ';':
case ',':
case '.':
case '<':
case '>':
case '?':
case '/':
return(@this.ExtractOperator(startIndex, out endIndex));
case '0':
if (pos < @this.Length && (@this[pos] == 'x' || @this[pos] == 'X'))
{
return(@this.ExtractHexadecimal(startIndex, out endIndex));
}
return(@this.ExtractNumber(startIndex, out endIndex));
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
return(@this.ExtractNumber(startIndex, out endIndex));
default:
if ((ch1 >= 'a' && ch1 <= 'z') || (ch1 >= 'A' && ch1 <= 'Z'))
{
return(@this.ExtractKeyword(startIndex, out endIndex));
}
endIndex = -1;
return(null);
}
throw new Exception("Invalid token");
}