code: function replacer(key, value) {
          if (!value) {
              return value;
          }
  
          const type = typeof value;
  
          if (type === 'object') {
              if (isRegExp(value)) {
                  return '@__R-' + UID + '-' + (regexps.push(value) - 1) + '__@';
              }
  
              return value;
          }
  
          if (type === 'function') {
              return '@__F-' + UID + '-' + (functions.push(value) - 1) + '__@';
          }
  
          return value;
      }
docs: Returns placeholders for functions and regexps (identified by index) which are later replaced by their string representation.