Benchmark: !! vs default if statement

HTML Preparation code:

<script src=''>
    var a = true;
</script>

Tests:

Default
if (window.a) return true;
!!
if (!!window.a) return true;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Default
!!

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36

Browser/OS: Chrome 109 on Windows

View result in a separate tab

Test name	Executions per second
Default	3524210.5 Ops/sec
!!	3476503.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared, and the pros and cons of different approaches.

**Benchmark Overview**

The benchmark is comparing two versions of an if statement: one using the null-coalescing operator (`!!`) and another without it (the "default" version). The test aims to determine which approach is faster on a desktop browser.

**Script Preparation Code**

The script preparation code is empty, indicating that no additional setup or initialization is required for the benchmark. This simplifies the test and allows for direct comparison between the two if statement versions.

**Html Preparation Code**

The HTML preparation code includes an empty `<script>` tag, which is used to initialize a variable `a` with a value of `true`. This setup ensures that the if statement will always evaluate to true, allowing us to compare the performance of the two if statement versions.

**Benchmark Definition JSON**

The benchmark definition provides two test cases:

1. **Default**: The first test case uses the traditional if statement without the null-coalescing operator (`if (window.a) return true;`).
2. **!!**: The second test case uses the if statement with the null-coalescing operator (`if (!!window.a) return true;`).

**Comparison**

The comparison between the two versions is straightforward:

* **Default** : Evaluates `window.a` directly.
* **!!** : Uses the null-coalescing operator to convert `window.a` to a boolean value (true or false), and then evaluates the resulting expression.

**Pros and Cons**

Here's a brief analysis of each approach:

* **Default**: Simple and straightforward, but may be slower due to potential type coercion.
	+ Pros: Easy to read and understand.
	+ Cons: May incur additional overhead due to type coercion.
* **!!**: Explicitly forces the evaluation of `window.a` as a boolean value.
	+ Pros: Avoids potential type coercion issues and can be faster.
	+ Cons: Requires knowledge of the null-coalescing operator.

**Library**

There is no explicit library mentioned in the benchmark definition. However, the use of `window` suggests that this benchmark may target browser-specific or cross-platform JavaScript environments.

**Special JS Feature/Syntax**

The null-coalescing operator (`!!`) is a special feature introduced in ECMAScript 2017 (ES2017). It allows explicit boolean conversion of a value, which can be useful in certain scenarios. This feature is supported by modern browsers and is not specific to any particular browser or platform.

**Alternatives**

Other alternatives for evaluating an if statement could include:

* Using `Boolean(a)` instead of `!!a` (although this would have the same effect).
* Using a ternary operator (`a ? true : false`) instead of a traditional if statement.
* Using `if (typeof a === 'boolean' && a) return true;` to explicitly check for boolean values.

Keep in mind that these alternatives may not provide the exact same performance characteristics as the benchmarking setup.

Related benchmarks:

!! vs default if statement (version: 0)

Comparing performance of: Default vs !!

Created: one year ago by: Guest

Jump to the latest result

Default

!!

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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