Works in Chrome, but breaks in Safari: Invalid regular expression: invalid group specifier name /(?<=\/)([^#]+)(?=#*)/ [duplicate]

Question

In my Javascript code, this regex /(?<=\/)([^#]+)(?=#*)/ works fine in Chrome, but in safari, I get:

Invalid regular expression: invalid group specifier name

Any ideas?

Answer 1

Looks like Safari doesn't support lookbehind yet (that is, your (?<=\/)). One alternative would be to put the / that comes before in a non-captured group, and then extract only the first group (the content after the / and before the #).

/(?:\/)([^#]+)(?=#*)/

Also, (?=#*) is odd - you probably want to lookahead for something (such as # or the end of the string), rather than a * quantifier (zero or more occurrences of #). It might be better to use something like

/(?:\/)([^#]+)(?=#|$)/

or just omit the lookahead entirely (because the ([^#]+) is greedy), depending on your circumstances.

Answer 2

Just wanted to put this out there for anyone who stumbles across this issue and can't find anything...

I had the same issue, and it turned out to be a RegEx expression in one of my dependencies, namely Discord.js .

Luckily I no longer needed that package but if you do, consider putting an issue out there or something (maybe you shouldn't even be running discord.js in your frontend react app).