code: function RANGE(from, to) {
          if (null == from || 1 != from.length || null == to || 1 != to.length) {
              throw 'Invalid args for RANGE';
          }
  
          return function (buffer, index, depth) {
              if (typeof depth === "undefined") { depth = 0; }
              var r;
              if (index < buffer.length && buffer.charAt(index) >= from && buffer.charAt(index) <= to) {
                  return R.ok(paka.P.RANGE, index, 1, null);
              } else {
                  r = R.error(paka.P.RANGE, index, null, 'Expects number in range [' + from + ', ' + to + ']');
                  _update_last_error(r);
                  return r;
              }
          };
      }
docs: Range: matches character in a range