Manual watch

Sometimes you might want to watch if store values used by some function changed, but you don't want it to re-run automatically.

manualWatch function allows exactly that. First argument is normal reaction callback, and 2nd one is callback that will be called each time some of store values used by the reaction changes

import { manualWatch } from 'statek';

const myStore = store({ count: 1 });

const callReaction = manualWatch(
  () => {
    return myStore.count;
  },
  () => {
    console.log('Count changed! Call reaction again to get fresh results!');
  },
);

manualWatch reaction will not start until we call it for the first time with

const currentCount = callReaction();

Stop manual reaction

If you want to stop receiving notifications about manual reaction used data updates, call callReaction.stop():

const callReaction = manualWatch(
  () => {
    // reaction content
  },
  () => {
    // change callback
  },
);

// later on
callReaction.stop();

Adding arguments

Manual reaction can accept any count of arguments:

const callReaction = manualWatch(
  multiplier => {
    return myStore.count * multiplier;
  },
  () => {
    // change callback
  },
);

callReaction(2);

caution

Calling manual reaction after it's stop function was called will throw an error.

Stop manual reaction#

Adding arguments#

caution

Stop manual reaction

Adding arguments