Echo JS 0.11.0

Saying "without loops" is a misnomer. This should've been titled something like "JavaScript functional array iteration" or similar.

No mention of reduce...

    Object.keys(obj)
      .map(k => foo(k, obj[k]))
      .reduce((a, b) => Object.assign(a, b), {});

that's one of my favorites... break up an object/hash map, do something to each, and reconstruct hash map... assuming `foo(k, v)` returns `{ [k]: bar(v) }`;

map is cool and powerful, but so is reduce.

Did you read the whole article? He mentions reduce towards the end.

My bad.. the data section in reduce was similar to filtering, I'd scrolled back to the top while reading, then back down, and got into filtering.