flatMap

flatMap function on IO allows you to change the IO to new IO.

Type

// IO<R, E, A>type: flatMap<R1 extends R, E1 extends E, B>(f: (val: A) => IO<R1, E1, B>): IO<R1, E, B>

Usage

io[IO<R, E, number>].flatMap((input) => new IO((value) => Either.Right(value + 1)))io[IO<R, E, number>].flatMap((input) => IO.fromFunction((value) => value + 1))io[IO<R, E, number>].flatMap(Console.flatIOLog)

Example

import { IO, Runtime, Either } from "ziojs";
const passInput = (input: number) => Either.Right(input);const addOne = (input: number) => Either.Right(input + 1);
const io = new IO(func);const addOneIO = new IO(addOne);
Runtime.unsafeRunSync(io.flatMap((input) => addOneIO.provide(input)).provide(4)) // 5Runtime.unsafeRunSync(io.flatMap(Console.flatIOLog).provide(4))

tip

Using chain method can reduce boilerplate code