ESLint Config Naming

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Variables (const / global) ​

  • Selector: variable with modifiers const, global
  • Allowed: camelCase, UPPER_CASE, PascalCase
  • Leading underscore: allowed

Why This Rule ​

Global constants serve different purposes and benefit from naming flexibility:

  • UPPER_CASE: Configuration constants (MAX_RETRIES, API_BASE_URL)
  • PascalCase: Singletons, factory exports, or namespace-like objects (AppConfig, Logger)
  • camelCase: Default export helpers or utility instances (defaultClient, mainRouter)
  • Leading underscore: Internal constants not meant for external use (_internalCache)

Global scope often contains objects that aren't simple values - they might be configured instances, singletons, or complex objects that deserve PascalCase treatment. This flexibility prevents forcing awkward names like LOGGER_INSTANCE when Logger is clearer.

Examples:

ts
// Configuration
export const MAX_RETRIES = 3; // WHY: UPPER_CASE shows a configuration constant

// Singleton instance
export const DatabaseConnection = createConnection(); // WHY: PascalCase indicates a named exported instance

// Utility instance
export const apiClient = new ApiClient(); // WHY: camelCase for runtime value

References:

✅ Good ​

ts
const MAX_RETRIES = 3; // WHY: UPPER_CASE for a true constant
const ApiBaseUrl = 'https://example.com'; // WHY: PascalCase used for exported namespace-like object

❌ Bad ​

ts
const max_retries = 3; // WHY: snake_case global const is discouraged