function isParamComplexArray (paramKey) {
  // this checks if parameter key numbered element (i.e. itemArray[1] is complex array param)
  let regex = /\[[\d]+\]/gm;
  return regex.test(paramKey);
}
Tests whether given parameter is of complex array type from param key

@param {*} paramKey - Parmaeter key that is to be tested
@returns {Boolean} - result