Benchmark: nullish assignment vs if 2

Script Preparation code:

var object;

Tests:

??=
object ??= {}
if
if (!object) { object = {} }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
??=
if

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 YaBrowser/24.7.0.0 Safari/537.36

Browser/OS: Yandex Browser 24 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
??=	23343858.0 Ops/sec
if	23076156.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided JSON data to understand what is being tested in this JavaScript microbenchmark.

**Benchmark Definition**

The benchmark definition represents two approaches for handling nullish values (i.e., values that are either null or undefined) in an object.

1. **Nullish Coalescing Operator (`??`)**
	* The script preparation code creates an empty object `var object;`.
	* The benchmark definition uses the nullish coalescing operator `object ??= {}`. This operator is available in JavaScript from ES2022.
	* The test name is `"??="`, which means it's testing the behavior of the nullish coalescing operator with this specific script.
2. **If-Null Check**
	* The script preparation code still creates an empty object `var object;`.
	* The benchmark definition uses an if-statement to check if the object is null or undefined, and then assigns a new object `{}` if it is: `if (!object) {\r\n  object = {}\r\n}`.
	* The test name is `"if"`, which means it's testing the behavior of this specific if-statement with this script.

**Pros and Cons**

1. **Nullish Coalescing Operator (`??`)**:
	* Pros:
		+ More concise and readable code.
		+ Reduces the need for explicit null checks.
	* Cons:
		+ Requires support for ES2022 syntax, which might not be available in older browsers or environments.
		+ Can lead to confusion if not used carefully.
2. **If-Null Check**:
	* Pros:
		+ Widely supported across older browsers and environments.
		+ More explicit about the intent of checking for null or undefined values.
	* Cons:
		+ Requires more code and is less concise.
		+ Can be slower due to the additional operation.

**Library and Special JS Feature**

There are no libraries mentioned in this benchmark. The only special feature being tested is the nullish coalescing operator (`??`), which was introduced in ES2022.

**Other Alternatives**

For handling nullish values, other approaches could include:

1. Using `||` (logical OR) operator: `object || {}`
2. Using a function that checks for null or undefined values: `function getOrDefault(object) { return object || {}; }`
3. Using a library like Lodash's `getIn()` method.

However, these alternatives might not be as concise or readable as the nullish coalescing operator (`??`), and their performance may vary depending on the specific use case.

**Additional Considerations**

When dealing with nullish values, it's essential to consider the following:

1. Nullability: Understanding whether a value can be null or undefined helps in choosing the right approach.
2. Concurrency: In multi-threaded environments, nullish checks might introduce additional overhead.
3. Performance: Optimize for performance by avoiding unnecessary checks and using efficient data structures.

I hope this explanation helps you understand what is being tested in this JavaScript microbenchmark!

Related benchmarks:

nullish assignment vs if 2 (version: 0)

Comparing performance of: ??= vs if

Created: one year ago by: Guest

Jump to the latest result

??=

if

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):