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Function: findLastAsync()

Returns an async iterable containing the last value of asyncIterable for which fn returns a value awaitable to a truthy value. Otherwise, returns an empty async iterable.

Example​

const asyncIterable = asAsync([1, 2, `sloth`, 4, `other string`])

console.log(
  await pipe(
    asyncIterable,
    findLastAsync(value => typeof value === `string`),
    orAsync(() => `yawn!`),
  ),
)
//=> other string

console.log(
  await pipe(
    asyncIterable,
    findLastAsync(value => Array.isArray(value)),
    orAsync(() => `yawn!`),
  ),
)
//=> yawn!

findLastAsync(fn)​

findLastAsync<Value>(fn): (asyncIterable) => AsyncOptional<Value>

Returns an async iterable containing the last value of asyncIterable for which fn returns a value awaitable to a truthy value. Otherwise, returns an empty async iterable.

Type Parameters​

• Value

Parameters​

• fn

Returns​

Function

Parameters​

• asyncIterable: AsyncIterable<Value, any, any>

Returns​

AsyncOptional<Value>

Example​

const asyncIterable = asAsync([1, 2, `sloth`, 4, `other string`])

console.log(
  await pipe(
    asyncIterable,
    findLastAsync(value => typeof value === `string`),
    orAsync(() => `yawn!`),
  ),
)
//=> other string

console.log(
  await pipe(
    asyncIterable,
    findLastAsync(value => Array.isArray(value)),
    orAsync(() => `yawn!`),
  ),
)
//=> yawn!

Defined in​

filters.d.ts:660

findLastAsync(fn, asyncIterable)​

findLastAsync<Value>(fn, asyncIterable): AsyncOptional<Value>

Returns an async iterable containing the last value of asyncIterable for which fn returns a value awaitable to a truthy value. Otherwise, returns an empty async iterable.

Type Parameters​

• Value

Parameters​

• fn

• asyncIterable: AsyncIterable<Value, any, any>

Returns​

AsyncOptional<Value>

Example​

const asyncIterable = asAsync([1, 2, `sloth`, 4, `other string`])

console.log(
  await pipe(
    asyncIterable,
    findLastAsync(value => typeof value === `string`),
    orAsync(() => `yawn!`),
  ),
)
//=> other string

console.log(
  await pipe(
    asyncIterable,
    findLastAsync(value => Array.isArray(value)),
    orAsync(() => `yawn!`),
  ),
)
//=> yawn!

Defined in​

filters.d.ts:660