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Comment by Waterluvian | Hacker News Reader

A built-in way to conveniently iterate n times.

Anyone have a sensible pure JavaScript example for:

    range(5).forEach(fn)

I haven't found one that felt small enough to use inline. It end up using traditional for loops.

Yeah, this

   for (var n in 5) // n is in [0..5)

should just work as it does in Sciter.

Using underscorejs or lodash:

    _.range(5).forEach(i => {/*...*/})

I really don't love it, but

    Array(5).fill().forEach(() => console.log('hello'))

I've also taken to:

    Array.from({ length: 5 }).forEach(...)

But I'm not sure what you gain from that compared to just wrapping a for loop in a function. You still don't get ranges the way you do in, say Ruby:

    ('a'..'z').each {|letter| puts letter }

Yeah, I mostly work in Python, where ranging and slicing is amazing. JS has a lot to catch up on in that regard.

Array.from({ length: 5 }).forEach(fn)

Oh not bad. I wasn't aware of that!

I'm guessing it constructs the whole array upfront. Maybe there's a generator way to do it too.