feat: 🎸 added custom memoize function

Author: Pratham82

2024 Prep/polyfills/memoization.js

@@ -0,0 +1,51 @@
+//* Write a memoization function
+
+function memoize(func) {
+  // create cache store
+  const cache = {}
+
+  return function (...args) {
+    // stringify the args
+    const keys = JSON.stringify(args)
+    // check if the args are in the cache
+    if (cache[keys]) {
+      // if present then call the cached function
+      console.log('Cache hit!')
+      return cache[keys]
+    } else {
+      // if args not present in cache recall the function
+      console.log('Cache miss!')
+      const result = func.apply(this, args)
+      // add the result in cache, for next calculation
+      cache[keys] = result
+      // return result
+      return result
+    }
+  }
+}
+
+const memoizeV2 = func => {
+  const cache = new Map()
+  return function (...args) {
+    const key = JSON.stringify(args)
+    if (cache.has(key)) {
+      return cache.get(key)
+    } else {
+      const result = func(...args)
+      cache.set(key, result)
+      return result
+    }
+  }
+}
+
+function expensiveOperation(n) {
+  console.log('Calculating...')
+  return n * 2
+}
+const memoizedOperation = memoizeV2(expensiveOperation)
+
+console.log(memoizedOperation(5)) // Output: Calculating... \n Cache miss! \n 10
+console.log(memoizedOperation(5)) // Output: Cache hit! \n 10
+console.log(memoizedOperation(5)) // Output: Cache hit! \n 10
+console.log(memoizedOperation(5)) // Output: Cache hit! \n 10
+console.log(memoizedOperation(5)) // Output: Cache hit! \n 10