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Discussion on: Practical Guide to Fp-ts: P3 — Task, Either, TaskEither

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Replies for: hey, great articles cycle. waiting for the next one! after you got T.Task<Error | Resp> from TaskEither how would you take the value out? wi...

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Ryan Lee • • Edited

Task is just a promise, so you can just await it and use an if statement.

import * as T from 'fp-ts/lib/Task'

type Resp = { code: number; description: string }

declare const task: T.Task<Error | Resp>
(async() => {
  const result = await task()
  if (result instanceof Error) {
    // Result is Error
  } else {
    // Result is Resp
  }
})()