Benchmark: React const vs function 2024

HTML Preparation code:

<script crossorigin src="https://unpkg.com/react@18/umd/react.production.min.js"></script>
<script crossorigin src="https://unpkg.com/react-dom@18/umd/react-dom.production.min.js"></script>
<div id="dest"></div>

Tests:

Const
const Hello = ({toWhat}) => React.createElement('div', null, `Hello ${toWhat}`); ReactDOM.render( React.createElement(Hello, {toWhat: 'Worldd'}, null), document.getElementById('dest') );
Function
function Hello({toWhat}){ return React.createElement('div', null, `Hello ${toWhat}`); } ReactDOM.render( React.createElement(Hello, {toWhat: 'Worldd'}, null), document.getElementById('dest') );

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Const
Function

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/124.0.0.0 Safari/537.36

Browser/OS: Chrome 124 on Windows

View result in a separate tab

Test name	Executions per second
Const	50475.7 Ops/sec
Function	27627.5 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested.

**Benchmark Overview**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The provided benchmark compares two approaches for creating React components: using `const` declarations versus using `function` declarations.

**Test Cases**

The benchmark consists of two test cases:

1. **Const**: This test case uses a constant declaration (`const Hello`) to define a function that returns a React element.
2. **Function**: This test case uses a regular function declaration (`function Hello`) to define the same function as in the `Const` test case.

**Library and Purpose**

The benchmark relies on two libraries:

1. **React**: A JavaScript library for building user interfaces. In this benchmark, React is used to render elements.
2. **ReactDOM**: A library that provides a way to render React components to the DOM.

In both test cases, React and ReactDOM are used to render a simple "Hello World" message to an HTML element with the id `dest`.

**Special JS Feature/Syntax**

There isn't any special JavaScript feature or syntax being tested in this benchmark. The focus is on comparing two different approaches for creating React components.

**Options Compared**

The benchmark compares the performance of two options:

1. **Const Declaration**: Using a constant declaration to define the function.
2. **Function Declaration**: Using a regular function declaration to define the same function.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Const Declaration**:
	+ Pros:
		- Faster execution times (as seen in the benchmark results)
		- Less memory allocation, as the constant is stored in memory only once
	+ Cons:
		- Limited flexibility, as changing the implementation of the function might require redefining the constant
* **Function Declaration**:
	+ Pros:
		- More flexible, as changes to the function implementation can be made without affecting the constant declaration
	+ Cons:
		- Slower execution times (as seen in the benchmark results)
		- More memory allocation, as a new instance of the function is created each time it's called

**Other Alternatives**

If you're looking for alternative approaches to create React components, you might consider:

* Using **arrow functions**, which provide a concise way to define small functions
* Using **classes**, which provide a way to define reusable components with state and lifecycle methods
* Using a **module bundler**, such as Webpack or Rollup, to manage dependencies and optimize performance

Keep in mind that these alternatives might not be directly comparable to the `const` vs. `function` declaration approach tested in this benchmark.

In summary, the benchmark compares the performance of two approaches for creating React components: using constant declarations versus function declarations. The results suggest that const declarations provide faster execution times and less memory allocation, but may limit flexibility.

Related benchmarks:

React const vs function 2024 (version: 0)

Comparing performance of: Const vs Function

Created: 2 years ago by: Guest

Jump to the latest result

Const

Function

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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