combineEvents

import { combineEvents } from 'patronum';
// or
import { combineEvents } from 'patronum/combine-events';

combineEvents(events)

since

patronum 2.1.0 Use combineEvents({ events }) with patronum < 2.1.0

Motivation

Method allows to trigger event when all of given events are triggered, with payloads of given events

Note

Consider using stores with combine in case of lazy-loaded modules, as they could miss some updates happened before module loaded

Formulae

const target = combineEvents({ key1: event1, key2: event2 });

• When all events are triggered, trigger target with {key1: firstPayload, key2: secondPayload}

const target = combineEvents([event1, event2]);

• When all events are triggered, trigger target with [firstPayload, secondPayload]

Arguments

1. events — Object or array with events

Returns

• target — Event with the same shape as events, that triggered after all events triggered

combineEvents({ events, reset, target })

Motivation

Object form which allow to pass reset unit or target

Formulae

const target = combineEvents({
  events: {
    key1: event1,
    key2: event2,
  },
  reset: resetUnit,
  target: targetUnit,
});

• When all events are triggered, trigger target with {key1: firstPayload, key2: secondPayload}

const target = combineEvents({
  events: [event1, event2],
  reset: resetUnit,
  target: targetUnit,
});

• When all events are triggered, trigger target with [firstPayload, secondPayload]

Arguments

1. events — Object or array with events
2. reset (Unit<any>) - Optional. Any unit which will reset state of combineEvents and collecting of payloads will start from scratch
3. target (Unit<Shape>) - Optional. Any unit with type matching events shape

Returns

• target — When target option is not defined, will return new event with the same shape as events, otherwise target unit will return

Example

const first = createEvent<number>();
const second = createEvent<string>();
const third = createEvent<boolean>();
const target = createEvent<{ a: number; b: string; c: boolean }>();
const reset = createEvent();

combineEvents({
  events: {
    a: first,
    b: second,
    c: third,
  },
  reset,
  target,
});

target.watch((object) => {
  console.log('first event data', object.a);
  console.log('second event data', object.b);
  console.log('third event data', object.c);
});

first(15); // nothing
second('wow'); // nothing
third(false); // target triggered with {a: 15, b: 'wow', c: false}

first(10);
second('-');

reset(); // combineEvents state is erased

third(true); // nothing, as it's a first saved payload
first(0);
second('ok'); // target triggered with {a: 0, b: 'ok', c: true}