diffusion/src/internal/util/memoize.js

Diffusion JavaScript client

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.memoize = void 0;
var MAXIMUM_CACHE_SIZE = 1000;
/**
 * Wrap a function with an automatic memoization layer.
 *
 * @param function the function to cache results for.
 * @param cache    the internal cache to use.
 * @param matcher  the matcher function to return a cache key from an array of arguments
 *
 * @returns        the memoized function
 */
function memoize(f, cache, matcher) {
    if (matcher === void 0) { matcher = JSON.stringify; }
    var c = function () {
        var args = [];
        for (var _i = 0; _i < arguments.length; _i++) {
            args[_i] = arguments[_i];
        }
        var a = matcher(args);
        var r = cache.get(a);
        if (r) {
            cache.delete(a);
            cache.set(a, r);
            return r;
        }
        r = f.apply(f, args);
        cache.set(a, r);
        if (cache.size > MAXIMUM_CACHE_SIZE) {
            var oldestKey = cache.keys().next().value;
            cache.delete(oldestKey);
        }
        return r;
    };
    // this is only used for unit testing to gain access to the uncached function
    c._uncached = f;
    return c;
}
exports.memoize = memoize;