JSFiddle - React, Tailwind, and code Playground

JavaScript

var obj = {
'name' : null,
'age' : 25,
'food': null
}

var newObj = {
'name' : null,
'food': null
}


function filterKeys(a, b) {
var firstKeys = Object.keys(a);
var secondKeys = Object.keys(b);
var missingKeys = firstKeys.filter(val => !secondKeys.includes(val));
return missingKeys;
}
var createdVarsAndFuncs = filterKeys(obj, newObj);
console.log(createdVarsAndFuncs);