Using OR in regex to replace multiple matches with JS replace()

Question

A few other answers to similar questions mention to simply use an | to do multiple matches, but it doesn't seem to be working in JS for me.

I have the following string: /hi_hawaii_zip_codes_geo.min.json and want to output hawaii.

The following code doesn't work: str.replace(/_z.*|^.{0,5}/, '') however, running _z.*|^.{0,5} matches fine on regexpal.com as a test, and I'm able to replace the correct matching substrings by chaining 2 replace()s.

Is there some special exception for regex in JS or replace that I'm overlooking?

[`/^.{0,4}|_z.*/g`](https://regexr.com/3rkcg) – Arman Charan Jun 27 '18 at 00:46 — Arman Charan, Jun 27 '18 at 00:46

score 2 · Answer 1 · answered Jun 27 '18 at 00:33

2

Add the global flag:

str.replace(/_z.*|^.{0,5}/g, '')
            add “g” —————-^

answered Jun 27 '18 at 00:33

Bohemian

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thank you! that's what I was missing, didn't realize the particularities of replace(). – Jacob Simmons Jun 27 '18 at 15:55

score 1 · Answer 2 · answered Jun 27 '18 at 01:26

1

It's not clear from the question why replace needs to be used at all. There are at least 2 other approaches to getting "hawaii" from the same str:

str.match(/_(.*?)_/)[1]

and

str.split('_')[1]

answered Jun 27 '18 at 01:26

cybersam

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Thanks! I was aware of split, but really wanted to work and improve my regex through this as well. – Jacob Simmons Jun 27 '18 at 15:54

Using OR in regex to replace multiple matches with JS replace()

2 Answers2