Dead Code

ID: dead_code | Severity: Low (default)

Dead code refers to exported functions, classes, or variables that are not imported or used anywhere else in the project.

Why this is a smell

• Maintenance Burden: Developers might spend time updating or refactoring code that isn't even used.
• Bundle Size: Increases the final application size (though many bundlers do tree-shaking).
• Confusion: Makes the API of a module appear larger and more complex than it actually is.

Examples

Bad

// utils.ts
export const usedHelper = () => { ... };
export const unusedHelper = () => { ... }; // Reported as dead code

// main.ts
import { usedHelper } from './utils';

How to fix

1. Delete it: If it's truly unused, the best action is removal.
2. Mark as Entry Point: If it's part of a public API or a dynamic import, add it to entry_points in your config.

Configuration

entry_points:
  - 'src/index.ts'
  - 'src/api/**/*.ts'

ESLint Rule

This detector is available as an ESLint rule for real-time feedback in your editor.

// eslint.config.js
export default [
  {
    rules: {
      '@archlinter/no-dead-code': 'warn',
    },
  },
];

See ESLint Integration for setup instructions.