An fp-ts style ADT to capture the concept of an Option in progress.

@nll/datum

ADT for asynchronous data updated to work with fp-ts@2+.

Version 3+ release only includes an es module build. It also references the fp-ts/es6 build.

Documentation

Full Documentation

Usage Example

``bash
npm i @nll/datum fp-ts
`

`typescript
import { sequenceT } from 'fp-ts/es6/Apply';
import { pipe } from 'fp-ts/es6/pipeable';

import {
DatumEither,
datumEither,
failure,
initial,
map,
pending,
success,
toRefresh
} from '../src/DatumEither';

const sequence = sequenceT(datumEither);

// Here are some DatumEithers
const someInitial: DatumEither = initial; // Type: Initial
const somePending: DatumEither = pending; // Type: Pending
const someSuccess: DatumEither = success('DATA!'); // Type: Replete>
const someFailure: DatumEither = failure('ERROR!'); // Type: Replete>

// Here are some Refreshing Datume
const someRefreshingSuccess = toRefresh(someSuccess); // Type: Refresh>
const someRefreshingFailure = toRefresh(someFailure); // Type: Refresh>

const result1 = pipe(
sequence(someInitial, somePending, someSuccess),
map(([a, b, c]) => a + b + c)
);
console.log(result1);
/**
* The initial short circuits the sequence
* result1 === initial
*/

const result2 = pipe(
sequence(someRefreshingSuccess, someRefreshingFailure),
map(([a, b]) => a + b)
);
console.log(result2);
/**
* The failure shortcircuits the sequence.
* result2 === refresh(left('ERROR!'))
*/

const result3 = pipe(
sequence(someSuccess, someRefreshingSuccess),
map(([a, b]) => a + b)
);
console.log(result3);
/**
* All values are good, so map is called, since one of the DatumEithers is refreshing, the sequence is refreshing
* result3 = refresh(right('DATA!DATA!'))
*/
``