#prefer-named-capture-group

#Configuration

import { defineConfig, js } from '@rslint/core';

export default defineConfig([
  js.configs.recommended,
  {
    rules: {
      'prefer-named-capture-group': 'error',
    },
  },
]);

#Rule Details

This rule enforces using named capture groups instead of numbered capture groups in regular expressions. Named capture groups make a regular expression's intent easier to read, and make the captured values easier to retrieve (match.groups.name instead of a numbered index that shifts if the pattern changes).

This rule checks regex literals as well as string patterns passed to the RegExp constructor (including through globalThis/window/self/global) when the pattern is statically determinable.

Examples of incorrect code for this rule:

const foo = /(ba[rz])/;
const bar = new RegExp("(ba[rz])");
const baz = RegExp("(ba[rz])");

foo.exec("bar")[1]; // Retrieve the group result.

Examples of correct code for this rule:

const foo = /(?<id>ba[rz])/;
const bar = new RegExp("(?<id>ba[rz])");
const baz = RegExp("(?<id>ba[rz])");
const xyz = /xyz(?:zy|abc)/;

foo.exec("bar").groups.id; // Retrieve the group result.

#Options

This rule has no configurable options.

#Differences from ESLint

• rslint doesn't follow a local alias assigned from the global RegExp constructor — const R = RegExp; new R("(a)") is not reported, while ESLint reports it.

#When Not To Use It

If you are targeting ECMAScript 2017 or older environments, you should disable this rule, because named capture groups are only supported in ECMAScript 2018 and newer environments.

#Original Documentation

• ESLint: prefer-named-capture-group
• Source code