regexp to get words up next, exists or not

Question

This regexp is matching strings after /ab. Also, i would like to match empty strings after /ab. How can i do that?. Thanks in advance.

const TelegramBot = require('node-telegram-bot-api');
const token = process.env.TOKEN;
const bot = new TelegramBot(token, { polling: true });

bot.onText(/\/ab (.+)/, (msg, match) => {
    const chatId = msg.chat.id
    const prompt = match[1]
    bot.sendMessage(chatId, prompt)
})

@ServeshChaturvedi for example if input is: '/ab'; prompt = '' (empty string), if input is: '/ab hello world'; prompt = 'hello world' — sonEtLumiere, Aug 08 '22 at 04:29
So the match is always nothing? Or is it everything after `/ab`? how would a guaranteed result of nothing be useful? — zer00ne, Aug 08 '22 at 04:36
@zer00ne i need to get anything after /ab, words or empty strings — sonEtLumiere, Aug 08 '22 at 04:39
@sonEtLumiere IC, ok see my [answer](https://stackoverflow.com/a/73272970/2813224). — zer00ne, Aug 08 '22 at 04:40

zer00ne · Accepted Answer · 2022-08-08T05:00:05.263

1

Use a lookbehind: /^(?![\s\S])|(?<=\/ab).*/g

A lookbehind (?<=) will match anything in front of it without being included in the actual match. ~~As for return an empty string, you'll need to explicitly return a "" if there's no match. You can change this line maybe:~~ Added an alternate ^(?!\[\s\S\])|

const rgx = new RegExp(/^(?![\s\S])|(?<=\/ab).*/, 'g');

const str = `/ab 1234 hdsso
/abksdfsioiowe
/ab
khbigigi7 
s366s7d /ab`;

let matches = [...str.matchAll(rgx)].flat();

console.log(matches);

Regex101

edited Aug 08 '22 at 05:00

answered Aug 08 '22 at 04:34

zer00ne

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your answer is usefull but that regexp doesn't work as i expected – sonEtLumiere Aug 08 '22 at 04:43
You want `/ab` included in the match? – zer00ne Aug 08 '22 at 04:46
no, only the words after /ab, also empty strings – sonEtLumiere Aug 08 '22 at 04:47
1

@sonEtLumiere see update – zer00ne Aug 08 '22 at 05:00

regexp to get words up next, exists or not

1 Answers1