Benchmark: reduce 20000 v2 - MeasureThat.net

Script Preparation code:

var list = [];
var LIMIT = 10000;

Tests:

spread
for(var i = 0; i < LIMIT; i++) list = [...list, {a:2}];
concat
for(var i = 0; i < LIMIT; i++) list == list.concat([{a:2}]);
push
for(var i = 0; i < LIMIT; i++) list.push({a:2});
assign to index
for(var i = 0; i < LIMIT; i++) list[list.length] = {a:2};

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
spread
concat
push
assign to index

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and its different aspects.

**Benchmark Definition**

The provided benchmark definition is represented by two JSON files: one for the overall benchmark setup and another for individual test cases.

* The **Overall Benchmark Setup**: This section defines the basic properties of the benchmark, such as its name, description, script preparation code, and HTML preparation code. In this case, the script prepares an array `list` with a fixed length of 10,000 elements, each containing a single property `'a'` set to the value `2`.
* The **Individual Test Cases**: This section defines four test cases, each representing a different approach to appending or modifying the array. These approaches are:
	1. **`spread`**: Uses the spread operator (`[...list, {a:2}]`) to append a new element to the end of the array.
	2. **`concat`**: Uses the `concat()` method to concatenate an array with a single-element array containing the property `'a'`.
	3. **`push`**: Uses the `push()` method to add a new element at the end of the array.
	4. **`assign to index`**: Assigns the value `{a:2}` directly to the last index of the array.

**Comparison and Options**

The benchmark compares these four different approaches for appending or modifying the array. The pros and cons of each approach are:

* **Spread Operator (`[...list, {a:2}]`)**:
	+ Pros: Concise, efficient, and readable.
	+ Cons: May not work as expected in older browsers or environments that don't support the spread operator.
* **`concat()` Method**:
	+ Pros: Widespread support, easy to read, and well-documented.
	+ Cons: Can be slower than other approaches, especially for large arrays.
* **`push()` Method**:
	+ Pros: Fast, efficient, and widely supported.
	+ Cons: Less readable than other approaches, as the length of the array needs to be accessed explicitly.
* **Assigning to Index (`list[list.length] = {a:2}`)**:
	+ Pros: Fast, efficient, and concise.
	+ Cons: May not work as expected if the index is calculated dynamically or if the array length changes.

**Libraries and Special JS Features**

In this benchmark, none of the test cases explicitly use any libraries. However, it's worth noting that some of these approaches may rely on modern JavaScript features, such as:

* The spread operator (`[...list, {a:2}]`)
* Template literals (not directly used here but might be relevant for similar patterns)

**Other Alternatives**

There are other ways to append or modify an array in JavaScript. Some alternatives include:

* Using the `Array.prototype.push()` method with a callback function
* Using the `Array.prototype.unshift()` method to add elements at the beginning of the array
* Using the `Array.prototype.splice()` method to replace or insert elements

It's essential to consider factors such as performance, readability, and compatibility when choosing an approach for appending or modifying arrays in JavaScript.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.87 Safari/537.36

Browser/OS: Chrome 80 on Linux

View result in a separate tab

Test name	Executions per second
spread	0.3 Ops/sec
concat	0.4 Ops/sec
push	477.5 Ops/sec
assign to index	209.6 Ops/sec

Related benchmarks:

reduce 20000 v2 (version: 0)

Comparing performance of: spread vs concat vs push vs assign to index

Created: 4 years ago by: Guest

Jump to the latest result

spread

concat

push

assign to index

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):