Unicode regex \p{L} not working in NodeJS

Question

I am trying to make the following unicode regular expression work in nodejs, but all I get is an invalid escape error. I can't figure out, what to escape here or if this for some reason doesn't work at all in node. This is my original regex:

/([\p{L}|\-]+)/ug

If I escape the \p like \\p, the regex doesn't work anymore (outputs only p,L and -)

This works in chrome, so it should work in node somehow too, right? Thanks for your help.

var str = "thÛs Ís spå-rtÅ!";

console.log(str.match(/([\p{L}|\-]+)/ug))

Answer 1

A quick look through the nodejs changelog revealed this PR:

https://github.com/nodejs/node/pull/19052

which most notably states:

RegExp Unicode Property Escapes are at stage 4 and will be included in ES2018. They are available since V8 6.4 without a flag so they will be unflagged in Node.js v10. They are also available under the --harmony_regexp_property flag in Node.js v6-v9 and under the --harmony flag in Node.js v8-v9.

So by the look of it, if you are on node v6-v9, you can enable this feature by running node with a flag. For example, this works for me on node v8.11.3:

node --harmony regex-test.js

(where regex-test.js contains your sample code). Running this without the flag gives your Invalid escape error.

If you can update your node version to v10+, no flag is needed.