singleton

singleton.ts

class ConfigService {
  private static instance: ConfigService;
  private config = { apiUrl: 'https://api.example.com' };

  private constructor() {} // // Private constructor prevents direct instantiation

  static getInstance(): ConfigService {
    if (!ConfigService.instance) {
      ConfigService.instance = new ConfigService();
    }
    return ConfigService.instance;
  }

  getApiUrl() {
    return this.config.apiUrl;
  }
}

// Usage
const config1 = ConfigService.getInstance();
const config2 = ConfigService.getInstance(); // // true - same instance!