Private member naming (ARCH3009)

Key typescript.naming.private-member-naming · Severity info · Category naming

Private/non-public members should follow the language’s privacy-signalling convention, which in TypeScript is a leading underscore. This visually separates internal state from the public API.

Incorrect

class Cache {
  private store = new Map<string, unknown>();
  private hitCount = 0;

  get(key: string) {
    return this.store.get(key);
  }
}

Correct

class Cache {
  private _store = new Map<string, unknown>();
  private _hitCount = 0;

  get(key: string) {
    return this._store.get(key);
  }
}

Fix

Prefix the private member name with a leading underscore to signal its privacy.