protected function parseNestedKeyPairHeader($nestedPairs)
    {
        return array_reduce(explode(';', $nestedPairs), function($result, $pair) {
            $keyVal = explode('=', $pair, 2);
            $key = trim(array_shift($keyVal));
            $val = trim(implode('=', $keyVal));
            if ($key !== '' && $val !== '') {
                $result[$key] = $val;
            }
            return $result;
        }, []);
    }
protected function parseNestedKeyPairHeader($nestedPairs)
    {
        return array_reduce(explode(';', $nestedPairs), function($result, $pair) {
            $keyVal = explode('=', $pair, 2);
            $key = trim(array_shift($keyVal));
            $val = trim(implode('=', $keyVal));
            if ($key !== '' && $val !== '') {
                $result[$key] = $val;
            }
            return $result;
        }, []);
    }
protected function parseNestedKeyPairHeader ( $ nestedPairs ) { return array_reduce ( explode ( ';' , $ nestedPairs ) , function ( $ result , $ pair ) { $ keyVal = explode ( '=' , $ pair , 2 ) ; $ key = trim ( array_shift ( $ keyVal ) ) ; $ val = trim ( implode ( '=' , $ keyVal ) ) ; if ( $ key !== '' && $ val !== '' ) { $ result [ $ key ] = $ val ; } return $ result ; } , [ ] ) ; }
Parse the any nested key-pair values in the header value

@param  string $nestedPairs
@return array
Parse the any nested key - pair values in the header value