[ 0 => '_DOUBLE_QUOTES_a\\xCC\\x8Ao\\xCC\\x88_DOUBLE_QUOTES_', 1 => 1, 2 => 'GRAPHEME_EXTR_COUNT', 3 => 2, 4 => '$next',]
[ 'result' => [ 'next' => 5, 'string' => 'ö', 'encoded' => 'o%CC%88', ], 'php_version' => '7.1.33 Linux x86_64',]