Benchmark: Array() vs new Array()

Tests:

Without "new"
Array(500)
With "new"
new Array(500)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Without "new"
With "new"

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser/OS: Chrome 132 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Without "new"	146494624.0 Ops/sec
With "new"	8647939.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Measuring the performance of creating an array in JavaScript is a fundamental benchmark, as it can have significant implications for various aspects of web development.

**What's being tested?**

The provided benchmark tests two approaches to create an empty array: using `Array()` and `new Array()`. The test aims to determine which method is faster and more efficient.

**Options compared:**

1. **Using `Array()`**: This approach creates a new instance of the `Array` constructor without the `new` keyword.
2. **Using `new Array()`**: This approach creates a new instance of the `Array` constructor with the `new` keyword.

**Pros and Cons of each approach:**

* Using `Array()`: This method is more concise and doesn't require the use of the `new` keyword, making it a popular choice in JavaScript. However, some older browsers or versions might not support this syntax.
* Using `new Array()`: This method is more explicit and ensures that a new instance of the `Array` constructor is created, regardless of the browser version.

**Other considerations:**

The choice between these two methods depends on the specific use case and target audience. If the code needs to be compatible with older browsers or versions, using `new Array()` might be necessary. However, in modern JavaScript development, using `Array()` is generally preferred for its conciseness and readability.

**Library usage:**

There is no library used in this benchmark.

**Special JS feature/syntax:**

None of the test cases use any special JavaScript features or syntax that would require additional explanation.

**Benchmark preparation code and definition:**

The provided benchmark definition json includes a script preparation code, which is empty. This means that no code needs to be executed before running the benchmark. The HTML preparation code is also empty, indicating that no specific HTML setup is required for this benchmark.

**Alternatives:**

Other alternatives to test the performance of creating an array in JavaScript include:

* Using `Array.from()` or `Array.prototype.fill()`
* Creating an array with a constructor function (e.g., `function MyArray() { }`)
* Using a library like Lodash or Underscore.js, which might provide optimized array creation methods.

However, these alternatives are not included in the provided benchmark, and it's likely that the test is focused on comparing the performance of the two most common approaches: using `Array()` and `new Array()`.

Related benchmarks:

Array() vs new Array() (version: 0)

Comparing performance of: Without "new" vs With "new"

Created: one year ago by: Guest

Jump to the latest result

Without "new"

With "new"

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):