Don't use object properties
// ❌ wrong use of Map
const wrongMap = new Map();
wrongMap['key1'] = 'value1'; // add "object properties"❗️
wrongMap['key2'] = 'value2';
// ✅ correct use of Map
const dict = new Map();
dict.set('Jessie', {phone: "213-555-1234", address: "123 N 1st Ave"});
dict.set('Hilary', {phone: "617-555-4321", address: "321 S 2nd St"});
// --------------- log ---------------
[
wrongMap, // {key1: 'value1', key2: 'value2'} ⭐️
wrongMap.has('key1'), // false❗️
wrongMap.delete('key2'), // false❗️ (no such key)
'---------------------',
dict, // {} (object Map) ⭐️
dict.has('Jessie'), // true
dict.delete('Raymond'), // false (no such key)
dict.delete('Hilary'), // true (key deleted successfully)
dict.get('Hilary'), // undefined (no such key)
dict.get('Jessie'), // {phone: "213-555-1234", address: "123 N 1st Ave"}
dict.size, // 1
].forEach(x => log(x));
codepen ⟩ Map: don't use object properties❗️
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