Regex issues

[No3371]

Example

    1.  「ことの葉は強 (こは) く見ゆれどすまひ草露には―・つるものにざりける」〈[源順集](https://dictionary.goo.ne.jp/word/person/%E6%BA%90%E9%A0%86/#jn-212920)〉

Issues

1. ^ 1. 「(.+)\n(?! 2.) expected to work but failed to match, does amber support Negative Look Ahead?
2. ^ 1. 「(.+)\n matching works but replacing does not, it failed to capture.
   >「$1 replacement result:

   Expected: 1. 「ことの葉は強 (こは) く見ゆれどすまひ草露には―・つるものにざりける」〈[源順集](https://dictionary.goo.ne.jp/word/person/%E6%BA%90%E9%A0%86/#jn-212920)〉
   Returned: > 1. 「

3. As other have reported, amber does not support \n in replacement string.

[danopia]

As far as Negative Look Ahead, it looks like rust regex chooses to not have look aheads because of unpredictable performance.

• Does not support (?!...) negative lookahead assertion? rust-lang/regex#127