In the article when comparing the native vs lodash implementation the native one is given as: persons .map(p => ({ ...p, age: p.age + 1 })) .filter(p => p.age >= 30) .slice(0, 5); ^ But this is intentionally(?) unoptimized. You would instead put the filter and slice first, i.e. person.filter(p => p.age >= 29) .slice(0,5) .map(p => ({...p, age: p.age + 1})
Yes, but this will still filter through all the items, instead of stopping at 5.
I don't see how lodash could possibly filter a list of 30 by a criteria without visiting each item at least once to take a look at it. the only way to make it more efficient would be to have lodash collect the desired transformations (filter/map) and then run a single loop over the items, mapping only those items that meet the filter criteria. But that is not much more efficient than the [].filter().map() that you could do with native methods.