@mightyplow/jslib/function/memoize.js

js helpers library

import removeProp from '../object/removeProp';

/**
 * Caches a function result for a specified time.
 *
 * @memberOf function
 *
 * @param {function} fn - the function of which the result should be cached
 * @param {number} [timeout] - the time in ms which tells the time after which the results should be deleted from the cache
 * @returns {function}
 */
var memoize = function memoize(fn, timeout) {
    var cache = {};
    var removeCachedValue = function removeCachedValue(key) {
        return function () {
            return removeProp(cache)(key);
        };
    };

    return function () {
        for (var _len = arguments.length, args = Array(_len), _key = 0; _key < _len; _key++) {
            args[_key] = arguments[_key];
        }

        var key = JSON.stringify(args || []);

        if (!(key in cache)) {
            cache[key] = fn.apply(undefined, args);

            // clear cached value after timeout
            !isNaN(timeout) && setTimeout(removeCachedValue(key), timeout);
        }

        return cache[key];
    };
};

export default memoize;