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ReadableBase.prototype.flatMap - stream - Node documentation
method ReadableBase.prototype.flatMap

Usage in Deno

import { ReadableBase } from "node:stream";
ReadableBase.prototype.flatMap(
fn: (
data: any,
options?: Pick<ArrayOptions, "signal">,
) => any
,
options?: ArrayOptions,
): Readable

This method returns a new stream by applying the given callback to each chunk of the stream and then flattening the result.

It is possible to return a stream or another iterable or async iterable from fn and the result streams will be merged (flattened) into the returned stream.

Parameters

fn: (
data: any,
options?: Pick<ArrayOptions, "signal">,
) => any

a function to map over every chunk in the stream. May be async. May be a stream or generator.

optional
options: ArrayOptions

Return Type

Readable

a stream flat-mapped with the function fn.