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Function: filterMapAsync()

Returns an async iterable containing the values of asyncIterable transformed by fn in iteration order excluding the values for which fn returns a value awaitable to null or undefined.

Example​

import { asAsync, filterMapAsync, pipe, reduceAsync, toArray } from 'lfi'

const API_URL = `https://api.dictionaryapi.dev/api/v2/entries/en`

console.log(
  await pipe(
    asAsync([
      { sloth: `sloth` },
      { sloth: `lazy` },
      { notSloth: `active` },
      { sloth: `sleep` },
      { notSloth: `awake` },
    ]),
    filterMapAsync(async object => {
      if (!object.sloth) {
        return null
      }

      const response = await fetch(`${API_URL}/${object.sloth}`)
      return (await response.json())[0].phonetic
    }),
    reduceAsync(toArray()),
  ),
)
//=> [ '/slɑθ/', '/ˈleɪzi/', '/sliːp/' ]
Playground

Since​

v0.0.1

Call Signature​

filterMapAsync<From, To>(fn): (asyncIterable) => AsyncIterable<NonNullable<To>, any, any>

Type Parameters​

• From

• To extends [] | unknown[]

Parameters​

fn​

(value) => MaybePromiseLike<undefined | null | To>

Returns​

Function

Parameters​

asyncIterable​

AsyncIterable<From, any, any>

Returns​

AsyncIterable<NonNullable<To>, any, any>

Defined in​

filters.d.ts:228

Call Signature​

filterMapAsync<From, To>(fn, asyncIterable): AsyncIterable<NonNullable<To>, any, any>

Type Parameters​

• From

• To extends [] | unknown[]

Parameters​

fn​

(value) => MaybePromiseLike<undefined | null | To>

asyncIterable​

AsyncIterable<From, any, any>

Returns​

AsyncIterable<NonNullable<To>, any, any>

Defined in​

filters.d.ts:231

Call Signature​

filterMapAsync<From, To>(fn): (asyncIterable) => AsyncIterable<NonNullable<To>, any, any>

Type Parameters​

• From

• To

Parameters​

fn​

(value) => MaybePromiseLike<undefined | null | To>

Returns​

Function

Parameters​

asyncIterable​

AsyncIterable<From, any, any>

Returns​

AsyncIterable<NonNullable<To>, any, any>

Defined in​

filters.d.ts:236

Call Signature​

filterMapAsync<From, To>(fn, asyncIterable): AsyncIterable<NonNullable<To>, any, any>

Type Parameters​

• From

• To

Parameters​

fn​

(value) => MaybePromiseLike<undefined | null | To>

asyncIterable​

AsyncIterable<From, any, any>

Returns​

AsyncIterable<NonNullable<To>, any, any>

Defined in​

filters.d.ts:239