#radix

#Configuration

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

export default defineConfig([
  js.configs.recommended,
  {
    rules: {
      'radix': 'error',
    },
  },
]);

#Rule Details

This rule enforces that parseInt() and Number.parseInt() are called with an explicit radix argument. Without a radix, parseInt defaults to decimal for most inputs but previously inferred 16 for strings starting with 0x (and some implementations inferred 8 for strings starting with 0), which made the behavior hard to predict. Passing an explicit radix eliminates the ambiguity.

The rule reports three kinds of problems:

• No arguments — parseInt() is called with no arguments at all.
• Missing radix — parseInt(s) is called with only the string argument. A suggestion fix is offered that inserts , 10 (or 10, when a trailing comma is present) to pass the decimal radix explicitly.
• Invalid radix — the second argument is a literal (or the identifier undefined) that cannot be an integer between 2 and 36.

Examples of incorrect code for this rule:

parseInt();
parseInt("071");
parseInt("071", "abc");
parseInt("071", 37);
parseInt("071", 10.5);
Number.parseInt();
Number.parseInt("071");

Examples of correct code for this rule:

parseInt("071", 10);
parseInt("071", 8);
parseInt("071", foo);
Number.parseInt("071", 10);
parseFloat(someValue);

#Options

The rule accepts a deprecated string option ("always" or "as-needed"). It is preserved for backward compatibility and does not change the rule's behavior — a radix argument is always required regardless of the option.

#Original Documentation

• ESLint rule documentation