Type alias PartializedUnion<T, AllKeys>

PartializedUnion<T> creates a union type where each member has its own properties as required, while properties from other members of the union are made optional and set to undefined. This is useful for cases where different configurations or variants in a union require only their specific fields.

Example

type Config = PartializedUnion<
  | { dbConnectionString: string; maxConnections: number }
  | { apiEndpoint: string; apiKey: string }
  | { storageBucket: string; accessKeyId: string; secretAccessKey: string }
>;

// Example usage:
function configureService(config: Config) {
  if (config.dbConnectionString) {
    console.log(`Configuring database with connection string ${config.dbConnectionString}`);
  } else if (config.apiEndpoint) {
    console.log(`Configuring API with endpoint ${config.apiEndpoint}`);
  } else if (config.storageBucket && config.accessKeyId && config.secretAccessKey) {
    console.log(`Configuring storage bucket ${config.storageBucket}`);
  } else {
    console.log('Invalid configuration');
  }
}

configureService({ dbConnectionString: 'postgres://...', maxConnections: 100 });
configureService({ apiEndpoint: 'https://api.example.com', apiKey: '1234' });
configureService({ storageBucket: 'my-bucket', accessKeyId: 'AKIA...', secretAccessKey: 'abcd' });
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