React useMapbox hook in ES6

use-mapbox.js

import mapboxgl from 'mapbox-gl/dist/mapbox-gl-csp'
import MapboxWorker from 'worker-loader!mapbox-gl/dist/mapbox-gl-csp-worker' // Load worker code separately with worker-loader

import 'mapbox-gl/dist/mapbox-gl.css'

export const useMapbox = (opts) => {
  mapboxgl.workerClass = MapboxWorker
  mapboxgl.accessToken = "public/private access token"

  const init = (sources) => {
    const [poisA, poisB, poisC] = sources

    const map = new mapboxgl.Map(opts)
    map.on('load', () => {
      // defaults for map load event
    })

    // add any other default event handlers for map (operate on sources)

    return map
  }

  return init
}

Thank you for such a detailed breakdown of the code!