Type Alias: Either<T>

type Either<T>: {
  error: Error;
  result: undefined;
 } & [Error, undefined] | {
  error: undefined;
  result: T;
 } & [undefined, T];

type Either<T>: {
  error: Error;
  result: undefined;
 } & [Error, undefined] | {
  error: undefined;
  result: T;
 } & [undefined, T];

type Either<T>: {
  error: Error;
  result: undefined;
 } & [Error, undefined] | {
  error: undefined;
  result: T;
 } & [undefined, T];

type Either<T>: {
  error: Error;
  result: undefined;
 } & [Error, undefined] | {
  error: undefined;
  result: T;
 } & [undefined, T];

Either type represents a data structure that encapsulates a successful result or an Error. It wraps the result of a Promise in an object, making it easier to handle errors by returning an object that either contains a 'result' value of type T (if successful), or an 'error' of type Error.

Type Parameters