79 lines
2.4 KiB
Plaintext
Executable File
79 lines
2.4 KiB
Plaintext
Executable File
//
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// Main
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//
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export default function memoize(fn, options) {
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var cache = options && options.cache ? options.cache : cacheDefault;
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var serializer = options && options.serializer ? options.serializer : serializerDefault;
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var strategy = options && options.strategy ? options.strategy : strategyDefault;
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return strategy(fn, {
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cache: cache,
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serializer: serializer,
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});
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}
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//
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// Strategy
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//
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function isPrimitive(value) {
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return (value == null || typeof value === 'number' || typeof value === 'boolean'); // || typeof value === "string" 'unsafe' primitive for our needs
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}
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function monadic(fn, cache, serializer, arg) {
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var cacheKey = isPrimitive(arg) ? arg : serializer(arg);
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var computedValue = cache.get(cacheKey);
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if (typeof computedValue === 'undefined') {
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computedValue = fn.call(this, arg);
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cache.set(cacheKey, computedValue);
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}
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return computedValue;
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}
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function variadic(fn, cache, serializer) {
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var args = Array.prototype.slice.call(arguments, 3);
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var cacheKey = serializer(args);
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var computedValue = cache.get(cacheKey);
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if (typeof computedValue === 'undefined') {
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computedValue = fn.apply(this, args);
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cache.set(cacheKey, computedValue);
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}
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return computedValue;
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}
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function assemble(fn, context, strategy, cache, serialize) {
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return strategy.bind(context, fn, cache, serialize);
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}
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function strategyDefault(fn, options) {
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var strategy = fn.length === 1 ? monadic : variadic;
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return assemble(fn, this, strategy, options.cache.create(), options.serializer);
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}
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function strategyVariadic(fn, options) {
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return assemble(fn, this, variadic, options.cache.create(), options.serializer);
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}
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function strategyMonadic(fn, options) {
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return assemble(fn, this, monadic, options.cache.create(), options.serializer);
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}
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//
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// Serializer
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//
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var serializerDefault = function () {
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return JSON.stringify(arguments);
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};
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//
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// Cache
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//
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function ObjectWithoutPrototypeCache() {
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this.cache = Object.create(null);
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}
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ObjectWithoutPrototypeCache.prototype.get = function (key) {
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return this.cache[key];
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};
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ObjectWithoutPrototypeCache.prototype.set = function (key, value) {
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this.cache[key] = value;
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};
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var cacheDefault = {
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create: function create() {
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// @ts-ignore
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return new ObjectWithoutPrototypeCache();
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},
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};
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export var strategies = {
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variadic: strategyVariadic,
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monadic: strategyMonadic,
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};
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