Feature Request (sed): Support for extended match strings

[brc-dd]

I would like to request support for expressions like this:

sed -i ':a;N;$!ba;s/\n/ /g' file

Refer: https://stackoverflow.com/a/1252191/11613622

Currently, it is only supported by GNU sed; can be considered as low-priority (though the linked SO thread has over 2M views).

[nfischer]

Is any of this supported by JavaScript regex?

[brc-dd]

@nfischer The branching and flow control part (:a;N;$!ba;) is not there in JS regex. The substitution (s/\n/ /g) can be directly done using JS replace.

Here are the official docs BTW: https://www.gnu.org/software/sed/manual/html_node/Multiline-techniques.html, https://www.gnu.org/software/sed/manual/html_node/Branching-and-flow-control.html

[nfischer]

Hmm OK. Anything beyond simple regex support is unlikely to be supported. If you can refactor to use other unix commands instead (ex. see my replies on #983), I recommend using that workaround.

[brc-dd]

@nfischer Thanks. Well, I'm simply using replace with \n as match string for this particular case.