Home > JavaScript Questions > What is Memoization?
Memoization is a programming technique that attempts to increase a function’s performance by caching its previously computed results.
Because JavaScript objects behave like associative arrays, they are ideal candidates to act as caches.
Each time a memoized function is called, its parameters are used to index the cache.
If the data is present, then it can be returned, without executing the entire function.
However, if the data is not cached, then the function is executed, and the result is added to the cache.
The function is an integral part of the programming, they help in modularity and reusability to our code, as per above definition memoization is optimizing our code.
const memoizedAdd = () => {
let cache = {};
return (value) => {
if (value in cache) {
console.log('Fetching from cache');
return cache[value];
}
else {
console.log('Calculating result');
let result = value + 10;
cache[value] = result;
return result;
}
}
}
// returned function from memoizedAdd
const newAdd = memoizedAdd();
console.log(newAdd(9)); //output: 19 calculated
console.log(newAdd(9)); //output: 19 cached
from the above code, you can understand memoization.