Run results for: double equals null vs boolean

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.1.1 Safari/605.1.15

Browser: Safari 13

Operating system: Mac OS X 10.14.6

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
== null	1908542.0 Ops/sec
implicit boolean conversion	1898400.0 Ops/sec
explicit boolean conversion	1907274.0 Ops/sec
typeof + triple equals null	1898105.0 Ops/sec

Script Preparation code:

var values = [(function*() {})(), undefined, null, {}];

Tests:

== null
let isIterable; for (const value of values) { isIterable = value != null && typeof value[Symbol.iterator] === "function"; }
implicit boolean conversion
let isIterable; for (const value of values) { isIterable = value && typeof value[Symbol.iterator] === "function"; }
explicit boolean conversion
let isIterable; for (const value of values) { isIterable = !!value && typeof value[Symbol.iterator] === "function"; }
typeof + triple equals null
let isIterable; for (const value of values) { isIterable = typeof value !== "undefined" && value !== null && typeof value[Symbol.iterator] === "function"; }