TaskEither Quick Reference

TaskEither = async operation that can fail. Its shape is () => Promise<Either<E, A>>: construction is lazy.

When to Use

• You need a quick fp-ts reference for async operations that can fail.
• The task involves API calls, Promise wrapping, or composing asynchronous error-handling pipelines.
• You want a concise cheat sheet for TaskEither operators and patterns.

Create

import * as TE from 'fp-ts/TaskEither'
import * as T from 'fp-ts/Task'