Memoize Pattern

Листинг

function memoize(fn, resolver) { 
  var memoized = function() { 
    var cache = memoized.cache, 
        key = resolver 
          ? resolver.apply(this, arguments) 
          : +new Date() + '' + arguments[0]; 
        
        return hasOwnProperty.call(cache, key) 
          ? cache[key] 
          : (cache[key] = fn.apply(this, arguments)); 
  } 
  memoized.cache = {}; 

  return memoized; 
}

Пример

var fibonacci = memoize(function(n) {
  return (n === 0 || n === 1) ? n : fibonacci(n - 1) + fibonacci(n - 2);
});
fibonacci(7); //return 13