Benchmark: isIteratorOrAsyncIterator

HTML Preparation code:

var a = (function *() {})();
var b = undefined;
var c = null;
var d = {next: () => ({value: 1, done: false})};

Script Preparation code:

var a = (function *() {})();
var b = undefined;
var c = null;
var d = {next: () => ({value: 1, done: false})};
var values = [a, b, c, d];

Tests:

null check with next typeof check
for (const value of values) { if (value != null && typeof value.next === "function") { } }
boolean check with next typeof check
for (const value of values) { if (value && typeof value.next === "function") { } }
boolean check with next boolean check
for (const value of values) { if (value && value.next) { } }
null or undefined with next typeof check
for (const value of values) { if (value !== undefined && value !== null && typeof value.next === "function") { } }
null or undefined with boolean next check
for (const value of values) { if (value !== undefined && value !== null && value.next) { } }

Rendered benchmark preparation results:

Previous results

Test case name	Result
null check with next typeof check
boolean check with next typeof check
boolean check with next boolean check
null or undefined with next typeof check
null or undefined with boolean next check

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Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.5 Safari/605.1.15

Browser/OS: Safari 13 on Mac OS X 10.14.6

Test name	Executions per second
null check with next typeof check	6533637.0 Ops/sec
boolean check with next typeof check	6526039.0 Ops/sec
boolean check with next boolean check	6400167.0 Ops/sec
null or undefined with next typeof check	907124.2 Ops/sec
null or undefined with boolean next check	917572.9 Ops/sec

isIteratorOrAsyncIterator (version: 0)