doesn't support positive or negative lookbehind syntax

[masukomi]

Positive lookbehind: (?<=Y)X, matches X, but only if there’s Y before it.
Negative lookbehind: (?<!Y)X, matches X, but only if there’s no Y before it.

[liudongmiao]

demo: https://jianyu.io/regulex/

[masukomi]

that demo link didn't include positive or negative lookbehind, but i fiddled with it and it looks good to me. Thanks :D

demo with positive lookbehind

demo with negative lookbehind