Custom Memoization Function in JavaScript

memo.ts

/**
 * This Gist demonstrates a simple yet effective implementation of a memoization function in JavaScript.
 * Memoization is an optimization technique used to speed up computer programs by storing the results of expensive function
 * calls and returning the cached result when the same inputs occur again.
 */

const memoMap = new Map();

const complexFunction = (a1: number[], a2: number[]): number => {
  // Simulate heavy calculations
  console.log("Performing heavy calculations...");
  return a1.reduce((acc, val) => acc + val, 0) + a2.reduce((acc, val) => acc + val, 0); // Example calculation
};

const memo = (a1: number[], a2: number[]) => {
  const key = JSON.stringify([ a1, a2 ]);

  if (memoMap.has(key)) {
    console.log("Returning cached result...");
    return memoMap.get(key);
  }

  const result = complexFunction(a1, a2);
  memoMap.set(key, result);

  return result;
};

// Example usage
console.log(memo([ 1, 2, 3 ], [ 4, 5 ])); // Performs calculation
console.log(memo([ 1, 2, 3 ], [ 4, 5 ])); // Returns cached result