Have any of you found cool ways of generating arrays in js. I don't have to do this very often, but this is the best way I've found to do it. const firstTenSqaures = Array.from(Array(10), (_, i) => i ** 2)

I’d suggest avoiding the Array constructor entirely - use { length: 10 } instead of Array(10).

Yeah, I know you can do that { length: 10 }, but that kind of looks like magic. Why should the Array constructor be avoided?

Because it creates a sparse array.

Right. I didn't think that would really matter here. What about? const tenTens = new Array(10).fill(10)

I'm not sure what qualifies as cool but generators provide a lot of fun! Array.from((function*() { for (let i = 0; i < 10; i++) yield i ** 2; })()); // [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

There's also a range proposal: Iterator.range()

That would also be good. I feel like the question could also be phrased, what's the least ugly way to do this in js :joy:

Please refer to the active thread: [image] Provide an easy way to create a new array, filled via a mapping function 💡 Ideas I "gathered some data" (actually, it was just personal experience) related to this. Look at this commit history . As you can see, we started with Arr…

That just returns [10, 10, 10, 10, 10, 10, 10, 10, 10, 10]. If you're looking for a range, Array.prototype.fill is probably not what you're looking for. Now if only we could get implementors to optimize it correctly.

I usually do something like: const myRange = [...new Array(33)] .map((item, index) => index + 10); But we really need a standard range functionality

Ranges and Generating Arrays in JavaScript

I have questions

graphemecluster January 19, 2023, 1:00am 9

Please refer to the active thread:

Topic		Replies	Views
Provide an easy way to create a new array, filled via a mapping function 💡 Ideas proposal	59	4594	February 16, 2023
Array.range() for generating sequences 💡 Ideas	5	1040	March 8, 2020
Array.create 💡 Ideas proposal	6	997	October 25, 2021
Range Syntax 💡 Ideas proposal	3	663	March 26, 2020
Array.massMake() 💡 Ideas	2	123	August 15, 2025

Ranges and Generating Arrays in JavaScript

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