Benchmark: new Array() vs []

Tests:

new Array()
const x = new Array()
[]
const x = []

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
new Array()
[]

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/110.0

Browser/OS: Firefox 110 on Linux

View result in a separate tab

Test name	Executions per second
new Array()	1089267840.0 Ops/sec
[]	1090963712.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of MeasureThat.net and explore what's being tested in this specific benchmark.

**Benchmark Overview**

The provided JSON represents a simple benchmark that compares two approaches: using the `new` keyword to create an empty array (`const x = new Array()`) versus simply assigning an empty array literal (`const x = []`). The benchmark is designed to measure the performance difference between these two approaches in different JavaScript engines.

**Options Compared**

The two options being compared are:

1. `const x = new Array()`: This approach uses the `new` keyword to create a new, empty array object.
2. `const x = []`: This approach directly assigns an empty array literal to the variable `x`.

**Pros and Cons of Each Approach**

**Using `new Array()`**

Pros:

* Explicitly creates a new, empty array object
* Can be useful for explicit control over array creation

Cons:

* May involve additional overhead due to the `new` keyword and potential internal array creation steps

**Using `[]`**

Pros:

* Directly assigns an empty array literal, which is optimized by JavaScript engines
* Typically faster and more efficient

Cons:

* May lead to confusion or misunderstandings about how arrays are created in JavaScript

**Other Considerations**

The benchmark does not account for the differences in array creation behavior between different JavaScript engines. Some older engines might have distinct behaviors or optimizations for array literals versus `new`-style array creation.

**Library Usage**

In this benchmark, none of the libraries are explicitly used. The focus is on comparing the performance of two basic approaches to creating empty arrays.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax involved in this benchmark. The test cases only involve standard JavaScript language constructs.

**Alternative Approaches**

If you're interested in exploring alternative approaches, consider the following:

* Using `Array.from()` to create an array from an iterable (e.g., `const x = Array.from([])`).
* Using `Array()` with a callback function to create an array of specific values (e.g., `const x = Array(10).fill(0)`).
* Using other libraries or frameworks that provide optimized array creation functions.

Keep in mind that these alternatives might not be directly comparable to the original benchmark, as they introduce additional complexity and potential performance variations.

Related benchmarks:

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

Comparing performance of: new Array() vs []

Created: one year ago by: Guest

Jump to the latest result

new Array()

[]

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):