is this `for (i in 1 until array.size)` the best equivalent to this? `for num in array[1:]`

# getting-started

[oday]

is this

for (i in 1 until array.size)

the best equivalent to this?

for num in array[1:]

[Roukanken]

what kind of "best" function are we using here?
readability? performance? minimum code length?

[oday]

literal translation, the sample below is python

[oday]

what I mean is that is there that kind of subscript kind of thing where you can say something like 1: to mean from 1 until the end

[Roukanken]

there is an drop(1) function, which copies whole iterable except the first x members
(unless it's a sequence, in sequence it works 👌)

[Roukanken]

so for example for (num in array.drop(1)) would work, but it would impact performance a bit, against the python version

[oday]

ok so the one I suggested in the beginning i guess is the most readable

[oday]

literally speaking

[Roukanken]

or you could turn into functional style:

array.asSequence()
    .drop(1)
    .map { ... }
    .forEach { ... }

[Roukanken]

doesn't play well with nested for cycles, which are hella common in python tho
refactoring them into functions helps tho

[Klitos Kyriacou]

Re:

ok so the one I suggested in the beginning i guess is the most readable

I think for (num in array.drop(1)) is more readable because you can use num directly for each element, instead of array[i]. But it's a matter of opinion; do what's more readable for you and your colleagues or whoever reads your code.

[Paul Griffith]

val array = intArrayOf(1, 2, 3)
array.sliceArray(1 until array.size)

on the JVM at least, sticking with arrays instead of dropping to sequences or lists is going to be a massive performance gain

[oday]

thanks