How to create an array containing 1…N

Question

I\'m looking for any alternatives to the below for creating a JavaScript array containing 1 through to N where N is only known at runt

Answer 1

It seems the only flavor not currently in this rather complete list of answers is one featuring a generator; so to remedy that:

const gen = N => [...(function*(){let i=0;while(i

which can be used thus:

gen(4) // [0,1,2,3]

The nice thing about this is you don't just have to increment... To take inspiration from the answer @igor-shubin gave, you could create an array of randoms very easily:

const gen = N => [...(function*(){let i=0;
  while(i++

And rather than something lengthy operationally expensive like:

const slow = N => new Array(N).join().split(',').map((e,i)=>i*5)
// [0,5,10,15,...]

you could instead do:

const fast = N => [...(function*(){let i=0;while(i++