The useCallback
hook is a feature provided by React, and it is not available in vanilla JavaScript. React's useCallback
is specifically designed to memoize functions to prevent unnecessary re-creations of the function reference, which can be useful in certain scenarios to optimize performance in React functional components.
If you are working with React, you can use the useCallback
hook like this:
import React, { useCallback } from 'react';
function MyComponent() {
const myFunction = useCallback(() => {
// Your function logic here
}, []); // Dependencies array
// Rest of your component code
}
However, if you are looking for a way to memoize functions in vanilla JavaScript without using React, you can create a simple memoization function. Here's a basic example using closure:
function useCallback(callback) {
const memoizedCallback = function (...args) {
if (!memoizedCallback.cache) {
memoizedCallback.cache = new Map();
}
const key = args.join('-');
if (memoizedCallback.cache.has(key)) {
return memoizedCallback.cache.get(key);
}
const result = callback(...args);
memoizedCallback.cache.set(key, result);
return result;
};
return memoizedCallback;
}
// Example usage:
const myFunction = useCallback((a, b) => {
console.log('Executing function with arguments:', a, b);
return a + b;
});
console.log(myFunction(1, 2)); // Output: Executing function with arguments: 1 2
console.log(myFunction(1, 2)); // Output: (No execution, result retrieved from cache)
Note that this is a simple memoization technique, and it may not cover all use cases or edge cases that React's useCallback
hook does. If you are working with React, it's recommended to use the useCallback
hook provided by React itself.