lodash.memoize

What is lodash.memoize?

The lodash.memoize package is a function from the Lodash library that creates a memoized version of a function that caches the result of function calls based on the arguments passed. This can improve performance by avoiding repeated calculations for the same inputs.

What are lodash.memoize's main functionalities?

Caching function results

This feature allows you to cache the result of an expensive function call. When the memoized function is called again with the same arguments, the cached result is returned instead of recalculating.

const _ = require('lodash.memoize');
const expensiveFunction = n => {
  console.log('Expensive calculation for', n);
  return n * n;
};
const memoizedExpensiveFunction = _.memoize(expensiveFunction);
console.log(memoizedExpensiveFunction(5));
console.log(memoizedExpensiveFunction(5));

Custom cache resolver

This feature allows you to provide a custom resolver function that determines the cache key for storing results. This is useful when you need to memoize functions that take complex arguments like objects or arrays.

const _ = require('lodash.memoize');
const memoizedFunctionWithResolver = _.memoize(expensiveFunction, (...args) => JSON.stringify(args));
console.log(memoizedFunctionWithResolver({ a: 1 }));
console.log(memoizedFunctionWithResolver({ a: 1 }));

Other packages similar to lodash.memoize

memoizee

Memoizee is a complete memoize/cache solution for JavaScript. It offers more advanced features like max age, max size, and pre-fetching which lodash.memoize does not have. It also allows for memoizing asynchronous functions.

fast-memoize

Fast-memoize is a high-performance memoization library that claims to be the fastest possible memoization library in JavaScript. It uses a simpler API and has fewer features than lodash.memoize, focusing on raw performance.

memoizerific

Memoizerific is another memoization library that is limited to a certain number of arguments but is very fast and has a small footprint. It is less feature-rich compared to lodash.memoize but is designed for speed and efficiency for functions with a limited number of arguments.

README

lodash.memoize v4.0.1

The lodash method _.memoize exported as a Node.js module.

Installation

Using npm:

$ {sudo -H} npm i -g npm
$ npm i --save lodash.memoize

In Node.js:

var memoize = require('lodash.memoize');

See the documentation or package source for more details.