Run results for: Delete or not delete

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36

Browser: Chrome 91

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 3 years ago

Tests:

Use delete
const content = '0'.repeat(53000); // ~53kb var cache = {}; let i = 100; // will give us ~5Mb while (i--) { const name = `item-${i}`; cache[name] = content; } // we will delete all 100 items function invalidateItem() { return true; } const invalidatedCache = (cache) => { const updatedCache = {}; Object.assign(updatedCache, cache); Object.keys(cache).filter(invalidateItem).forEach((name) => delete updatedCache[name]); return updatedCache; }; invalidatedCache(cache);
Use undefined
const content = '0'.repeat(53000); // ~53kb var cache = {}; let i = 100; // will give us ~5Mb while (i--) { const name = `item-${i}`; cache[name] = content; } // we will delete all 100 items function invalidateItem() { return true; } const invalidatedCache = (cache) => { const updatedCache = {}; Object.assign(updatedCache, cache); Object.keys(cache).filter(invalidateItem).forEach((name) => { updatedCache[name] = undefined; }); return updatedCache; }; invalidatedCache(cache);
Use filter and reduce
const content = '0'.repeat(53000); // ~53kb var cache = {}; let i = 100; // will give us ~5Mb while (i--) { const name = `item-${i}`; cache[name] = content; } // we will delete all 100 items function invalidateItem() { return true; } const invalidatedCache = (cache) => { const updatedCache = Object.keys(cache).filter(invalidateItem).reduce((cacheClone, key) => { cacheClone[key] = cache[key]; return cacheClone; }, Object.create(null)); return updatedCache; }; invalidatedCache(cache);