davidnagli

//useFirebase.js

import firebase from 'firebase';
import {useState, useEffect} from 'react';

export function useFirebase(refName){
  const [state, setState] = useState(null);

  useEffect(()=>{
    firebase.database().ref(refName).on('value', snapshot => {

davidnagli

// Readable version:
array.reduce((countsMap, item) => countsMap.set(item, countsMap.get(item) + 1 || 1), new Map)

// Minified version:
array.reduce((a,b)=>a.set(b,a.get(b)+1||1),new Map)