Benchmark: Boolean vs !! vs length

Script Preparation code:

var newArr = ['1', '2', '3', '4'];

Tests:

Test1
!!newArr.length
Test2
Boolean(newArr.length)
Test3
newArr.length > 0

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Test1
Test2
Test3

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/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Test1	120758184.0 Ops/sec
Test2	80472104.0 Ops/sec
Test3	112243696.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain the provided benchmark.

**What is being tested?**

The provided benchmark measures the performance of three different ways to check if an array has elements: using the double negation operator (`!!`), the `Boolean()` function, and comparing the length of the array with 0 (`newArr.length > 0`). The goal is to determine which approach is the fastest.

**Options being compared**

There are three options being compared:

1. `!!newArr.length`
2. `Boolean(newArr.length)`
3. `newArr.length > 0`

Each option has its pros and cons:

* **`!!newArr.length`**: This method uses a single operator to check if the array length is falsy (i.e., 0). It's concise and readable, but may incur additional overhead due to the double negation operation.
* **`Boolean(newArr.length)`**: This method creates a new `Boolean` object with the result of evaluating the array length as a boolean value. While it provides explicitness, it involves more operations and may be slower than the first option.
* **`newArr.length > 0`**: This method directly compares the array length to 0 using a greater-than operator. It's straightforward but may require additional computations due to potential type coercion.

**Library**

The benchmark uses no external libraries beyond what's built into JavaScript (e.g., `Boolean()`). However, some browsers may provide additional features or optimizations that could affect the results, such as just-in-time compilation or caching of common expressions.

**Special JS feature or syntax**

There are no special features or syntax mentioned in the provided benchmark. The tests only use standard JavaScript operators and constructs.

**Other alternatives**

To explore alternative approaches, one might consider:

* Using a library like `lodash` which provides a more concise version of the second option: `_.gt(newArr.length, 0)`
* Employing a more specialized data structure or algorithm for array manipulation
* Experimenting with different browsers or JavaScript engines to see if their optimizations affect performance

Keep in mind that the choice of approach often depends on specific use cases and requirements. The benchmark provided by MeasureThat.net is designed to help developers identify potential performance bottlenecks in everyday code.

In terms of optimizing this particular code, it's likely that the most significant improvements can be made by reducing unnecessary operations or leveraging browser-specific features that optimize common expressions (e.g., caching `newArr.length` before using it).

Related benchmarks:

Boolean vs !! vs length (version: 0)

Comparing performance of: Test1 vs Test2 vs Test3

Created: 2 years ago by: Guest

Jump to the latest result

Test1

Test2

Test3

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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