Meaning of variable in array as property name?

Question

var expertise = \'journalism\'
var person = {
    name: \'Sharon\',
    age: 27,
    [expertise]: {
        years: 5,
        interests: [\'international\', \'politics\'         


        

Answer 1

It is Computed property (ES2015) :

This is a sample:

var prop = 'foo';
var o = {
  [prop]: 'hey',
  ['b' + 'ar']: 'there'
};

and you may use :

console.log(o.foo)  // hey
console.log(o.bar)  // there