Benchmark: React useCallback hook vs inline function

HTML Preparation code:

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.13.1/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.13.1/umd/react-dom.production.min.js"></script>
<div id="root"></div>

Script Preparation code:

function ComponentWithInlineFunction() {
  const clickMe = evt => evt.preventDefault();
  return React.createElement('button', {onClick: clickMe}, 'Click me!');
}

function ComponentWithUseCallback() {
  const clickMe = React.useCallback(evt => evt.preventDefault(), []);
  return React.createElement('button', {onClick: clickMe}, 'Click me!');
}

Tests:

Inline
ReactDOM.render(React.createElement(ComponentWithInlineFunction), document.getElementById('root'))
Hooks
ReactDOM.render(React.createElement(ComponentWithUseCallback), document.getElementById('root'))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Inline
Hooks

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser/OS: Chrome 132 on Android

View result in a separate tab

Test name	Executions per second
Inline	285082.2 Ops/sec
Hooks	429352.5 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark and its results.

**What is being tested?**

The benchmark tests two approaches to handling event handling in React applications:

1. **Inline function**: In this approach, the `onClick` handler is defined inline within the component's render method. This means that every time the component is re-rendered, a new function object is created and assigned to the `onClick` property of the button element.
2. **React useCallback hook**: In this approach, the `onClick` handler is defined using the `useCallback` hook from React. The `useCallback` hook memoizes the function so that it's not recreated on every render.

**Comparison of options**

The two approaches have different performance characteristics:

* **Inline function**: This approach creates a new function object every time the component is re-rendered, which can lead to performance issues if the application is complex and has many event handlers.
* **React useCallback hook**: By memoizing the function using `useCallback`, React ensures that the function is only recreated when its dependencies change. This can provide better performance, especially in applications with a large number of event handlers.

**Pros and cons**

* **Inline function**:
	+ Pros: simple to implement, no additional dependencies required.
	+ Cons: creates new function objects on every render, can lead to performance issues.
* **React useCallback hook**:
	+ Pros: memoizes the function, reduces unnecessary re-renders, provides better performance.
	+ Cons: requires importing and using the `useCallback` hook from React.

**Library and its purpose**

In this benchmark, React is used as a library for building the components. The `ReactDOM.render()` method is used to render the React component tree into the DOM.

**Special JS feature or syntax**

The `useCallback` hook is a special JavaScript feature introduced in React 16.8. It allows you to memoize functions so that they're not recreated on every render.

**Other alternatives**

If you prefer not to use the `useCallback` hook, you can create your own solution using other techniques, such as:

* Creating a function and assigning it to a variable outside of the component's scope.
* Using a library like Lodash, which provides a `memoize` function for memoizing functions.

However, these alternatives may require more boilerplate code and may not provide the same level of performance benefits as using the `useCallback` hook.

Related benchmarks:

React useCallback hook vs inline function (version: 0)

Comparing performance of: Inline vs Hooks

Created: 3 years ago by: Guest

Jump to the latest result

Inline

Hooks

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):