Comment by RomanKornev
11 hours ago
Every single `reduce` can be replaced with a more intuitive `groupBy`, `partition`, `mapValues`, `keyBy`, etc.
Reduce can approximate anything, that doesn't mean we should use it.
My favorite antipattern is
items.reduce(
(acc, item) => ({
...acc,
[item.id]: item,
}), {}
);
Like, why? Not only is this ridiculously inefficient O(N^2), it's also longer and less understandable than "build a new map" version.
I think this along with the other answers discussing the difficulty remembering the specific arguments of `reduce` (especially when varying by language!) are key reasons. After reading this conversational thread, I think maybe Microsoft got it right with LINQ: - `Where` is perhaps more intuitive than `filter` - `Select` seems no worse than `map` by invoking SQL-like syntax - While `reduce` is preserved as `Aggregate`, provide `GroupBy` and other handy methods as the preferred methods. In the code I write, it's probably these other methods that get called 95+% of the time. Who wants to `Aggregate` when they can simply `Sum` for example?
This one doesn't seem expressible in those terms: