Why let a = [{}] and a.indexOf({}) -1?

Asked Jul 05 '19 at 14:38

Active Jul 05 '19 at 14:42

Viewed 45 times

IndexOf cannot find my object. Here is the JsFiddle

let a = [{}]
console.log(a.indexOf({}))

asked Jul 05 '19 at 14:38

TSR

6

Because `{} !== {}`. Try `a.indexOf(a[0])`. – jonrsharpe Jul 05 '19 at 14:39
1

Every distinct object is `!==` to every other object. – Pointy Jul 05 '19 at 14:39
When you compare objects it checks whether the two operands refer to the same object in memory. `indexOf` obviously use equality internally. `{} === {}` is `false` – Maheer Ali Jul 05 '19 at 14:40

0 Answers0