$s[abbbbbb]
$s
^s.match[(?=b);g][D]

$s[a
a
a
b
b
bbb]
^s.match[(?=[\nb]);g][D]

$s[bcbcabc]
$s
^s.match[(?=[bc]);g][D]

#empty match after last char test

$title[word1 word2]
$m[^title.match[\b()\b;g']]
^json:string[$m]