javascript collection group by code example

Example 1: javascript array group by id

var results = orgs.reduce(function(results, org) {
    (results[org.id] = results[org.id] || []).push(org);
    return results;
}, {})

Example 2: group by in javascript

let group = cars.reduce((r, a) => { console.log("a", a); console.log('r', r); r[a.make] = [...r[a.make] || [], a]; return r;}, {});console.log("group", group);