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JavaScript

Posted by Kip Yin
Kip Yin
4,847 Points

How to directly loop over array items?

In Python, it is possible to iterate through items directly, not just through their indices:

myList = list('abcd')

for x in myList:
    print(x)

This would print the letters a, b, c, d, which are all items in myList. How can I achieve this in Javascript?

Also, is list comprehension possible in JS? In Python,

myList = [2*x for x in range(10)]

would create a list of even numbers between 0 and 20.

What about in JS?

1 Answer

Thomas Nilsen
Thomas Nilsen
14,957 Points
Thomas Nilsen
Thomas Nilsen
14,957 Points

If you don't want to use indices you can do this:

const str = "this is a test"
str.split().forEach(l => console.log(l))

closest you get to list comprehensions (that I can think of), is this:

console.log([...Array(10)].map((_, i) => i * 2));
Kip Yin
Kip Yin
4,847 Points

Thanks again! lol

Kip Yin
Kip Yin
4,847 Points

Why can't you just do i => i * 2 in map?

Kip Yin
Kip Yin
4,847 Points

I think I got it... Just watched a video on prototypes.