Benchmark: arrcode - MeasureThat.net

Tests:

arr = ["", ...arr];
let arr = [1,2,3] arr = ["", ...arr];
arr.unshift("")
let arr = [1,2,3] arr.unshift("")

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
arr = ["", ...arr];
arr.unshift("")

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/127.0.0.0 Safari/537.36

Browser/OS: Chrome 127 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
arr = ["", ...arr];	59137544.0 Ops/sec
arr.unshift("")	23509996.0 Ops/sec

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

**Benchmark Definition**

The provided JSON defines a single benchmark called "arrcode" with no script preparation code, HTML preparation code, or description. This suggests that the benchmark is focused on testing the performance of JavaScript array operations.

**Individual Test Cases**

There are two test cases:

1. `let arr = [1,2,3]\r\narr = [\"\", ...arr];`

This test case creates an array `arr` with three elements and then uses the spread operator (`...`) to concatenate a new string element at the end of the array. The resulting array is assigned back to the original variable `arr`.

2. `let arr = [1,2,3]\r\narr.unshift(\"\")`

This test case creates an array `arr` with three elements and then uses the `unshift()` method to add a new string element at the beginning of the array.

**Options Compared**

In this benchmark, two different approaches are being compared:

* The spread operator (`...`) for concatenating elements to an array.
* The `unshift()` method for adding elements to the beginning of an array.

**Pros and Cons of Each Approach**

1. **Spread Operator (`...`):**
	* Pros:
		+ Creates a new array with the concatenated element(s) without modifying the original array.
		+ Can be more readable and concise in some cases.
	* Cons:
		+ Can lead to unnecessary memory allocation and copying of elements.
2. **`unshift()` Method:**
	* Pros:
		+ Modifies the original array, which can be beneficial for performance-critical code.
		+ Can be faster than using the spread operator when dealing with large arrays.
	* Cons:
		+ May not be as readable or concise as using the spread operator.

**Library and Syntax**

There is no specific library being used in these test cases. However, it's worth noting that JavaScript supports various libraries like Lodash for functional programming and other utility functions. The `...` spread operator is a built-in feature of JavaScript, introduced in ECMAScript 2015 (ES6).

**Special JS Features**

There are no special JavaScript features or syntax being used in these test cases. However, if we were to add more complexity, it could involve using modern features like async/await, promises, or iterators.

**Other Alternatives**

If you wanted to write similar benchmarks for other array operations, here are some options:

* Using `concat()` instead of the spread operator (`...`).
* Using `push()` and then creating a new array with the result.
* Using slicing (`arr.slice()`) followed by concatenation or appending elements directly.

Keep in mind that each approach has its pros and cons, and the choice of method depends on the specific use case and performance requirements.

Related benchmarks:

arrcode (version: 0)

Comparing performance of: arr = ["", ...arr]; vs arr.unshift("")

Created: one year ago by: Guest

Jump to the latest result

arr = ["", ...arr];

arr.unshift("")

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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