private char _decimal, _listSep, _percent;              // localized decimal separator, list separator, percent sign

        #endregion ** fields

        //---------------------------------------------------------------------------

        #region ** ctor

        public CalcEngine()
        {
            CultureInfo = CultureInfo.InvariantCulture;
            _tkTbl      = GetSymbolTable();
            _fnTbl      = GetFunctionTable();
            _vars       = new Dictionary <string, object>(StringComparer.OrdinalIgnoreCase);
            _cache      = new ExpressionCache(this);
            _optimize   = true;
#if DEBUG
            //this.Test();
#endif
        }
        char _decimal, _listSep, _percent;                // localized decimal separator, list separator, percent sign

        #endregion

        //---------------------------------------------------------------------------
        #region ** ctor

        public CalcEngine()
        {
            CultureInfo = CultureInfo.InvariantCulture;
            _tkTbl = GetSymbolTable();
            _fnTbl = GetFunctionTable();
            _vars = new Dictionary<string, object>(StringComparer.OrdinalIgnoreCase);
            _cache = new ExpressionCache(this);
            _optimize = true;
#if DEBUG
            //this.Test();
#endif
        }