How to find the last part of an address?

Question

JavaScript

There is a regular expression that looks for the part of the address string that matches the house number:

((?<!(д(ом)?|стр(оение)?|/|-)\.?\s*\d*)\d+((,?\s*(к(ор(п(ус)?)?)?\.?)\s*\d+)|(\s*[а-я])|(\s*/\s*\d+))?\s*$)

It definitely works .
But I can't use it in a script:

const addr = 'Россия, Республика Татарстан, Казань, улица Бутлерова, 41';
const regEx = new RegExp('((?<!(д(ом)?|стр(оение)?|/|-)\.?\s*\d*)\d+((,?\s*(к(ор(п(ус)?)?)?\.?)\s*\d+)|(\s*[а-я])|(\s*/\s*\d+))?\s*$)');
const beginStr = addr.match(regEx);
console.log('addr', addr)
console.log('regEx', regEx)
console.log('beginStr', beginStr)

This is expressed in the fact that the result in the console is displayed as null.
Please help me fix the script. LIVE DEMO here .

Answer 1

when you use regular expressions in js using the constructor RegExp, you should escape slashes
i.e. not 1 slash \, but 2 \\
well, or use a literal notation
https://jsfiddle.net/nick_sdk/8zh4o7cn/