This package provides useful projections and tools to build projections that can be customized.
npm install --save @coriolis/parametered-projectionimport { lastPayloadOfType } from '@coriolis/parametered-projection'
// This projection would return an array of all payloads of events with type "target event type"
const myProjection = ({ useState, useProjection }) => (
useState(0),
useProjection(lastPayloadOfType('target event type')),
(list, event) => [...list, event]
)Of course this code sample is not doing anything interesting. But parametered projections are really helpful in real world.