how to cache a function in javascript

To cache a function in JavaScript, you can use the concept of memoization. Memoization is the technique of storing the results of expensive function calls and returning the cached result when the same inputs occur again.

Here is an example of how to cache the Fibonacci sequence function using memoization:

index.tsx
function fibonacci(n, cache = {}) {
  if (cache[n]) {
    return cache[n]; // return cached result if available
  }
  if (n <= 1) {
    return n;
  }
  const result = fibonacci(n - 1, cache) + fibonacci(n - 2, cache);
  cache[n] = result; // store result in cache
  return result;
}
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In the above example, cache is an optional parameter that is used to store the cached results of the function. If the cached result is available for the given input, it immediately returns the cached result instead of recalculating the function's output. If the cached result is not available, it proceeds to calculate the output and caches the result for later use.

This technique can significantly improve the performance of your applications by reducing the number of expensive function calls.