Benchmark: New Array Object vs New Array Literal

Tests:

New Array Object
var arrayObject = new Array('hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world'); arrayObject.forEach(console.log)
New Array Literal
var arrayLiteral = ['hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world', 'hello', 'world']; arrayLiteral.forEach(console.log)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
New Array Object
New Array Literal

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36 Edg/98.0.1108.62

Browser/OS: Chrome 98 on Windows

View result in a separate tab

Test name	Executions per second
New Array Object	5247.3 Ops/sec
New Array Literal	5620.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and some pros and cons of each approach.

**Benchmark Definition**

The benchmark is comparing two approaches to create an array in JavaScript:

1. **New Array Object**: Creating an array using the `new` keyword followed by a constructor function that takes a variable number of arguments (in this case, a string with comma-separated values).
2. **New Array Literal**: Creating an array using square brackets `[]` and adding elements to it using the syntax `array[index] = value`.

**Script Preparation Code**

The script preparation code is empty, which means that the benchmark starts from scratch for each test case.

**Html Preparation Code**

The html preparation code is also empty, which suggests that the benchmark is running in a headless browser (i.e., without a visible user interface).

**Individual Test Cases**

There are two test cases:

1. **New Array Object**: This test case creates an array using the `new` keyword and assigns it to a variable named `arrayObject`. The script then loops through the array using `forEach` and logs each element to the console.
2. **New Array Literal**: This test case creates an array using square brackets and adds elements to it using the syntax `array[index] = value`. The script then loops through the array using `forEach` and logs each element to the console.

**Library Used**

There is no explicit library used in these test cases, but it's likely that a JavaScript runtime environment (e.g., V8) or a browser engine (e.g., Blink) provides the necessary functionality for creating arrays and executing loops.

**Special JS Features/Syntax**

Neither of these approaches uses any special JavaScript features or syntax. They are both standard JavaScript syntax.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

1. **New Array Object**:
	* Pros: Can be more explicit and easy to understand, especially for developers who prefer a functional programming style.
	* Cons: May incur performance overhead due to the creation of an object and the use of `new`.
2. **New Array Literal**:
	* Pros: Typically faster and more efficient than creating an array using `new`, as it avoids the overhead of object creation and can be optimized by the browser engine.
	* Cons: Can be less explicit and more prone to errors, especially for developers who are not familiar with this syntax.

**Other Alternatives**

Some alternative approaches to creating arrays in JavaScript include:

1. **Array constructor**: `new Array(10)`. This approach is similar to using `new` keyword, but it's a bit more concise.
2. **Array.from() method**: `Array.from([1, 2, 3], (value) => value).forEach((value) => console.log(value));`. This approach uses the `from()` method to create an array from an iterable source, such as an array or a string.

Keep in mind that these alternatives may have different performance characteristics and use cases compared to the original approaches being tested.

Related benchmarks:

New Array Object vs New Array Literal (version: 0)

Comparing performance of: New Array Object vs New Array Literal

Created: 2 years ago by: Registered User

Jump to the latest result

New Array Object

New Array Literal

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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