Suffix of list

Stream: new members

[Marcus Rossel]

Is there a way to get a suffix from a list, or more generally a slice of a list?
Something like:

[A, B, C, D, E, F].suffix 3 = [D, E, F]
[A, B].suffix 3 = []

[Yakov Pechersky]

A combination of take and reverse would work. Or if you know the length already, drop.

[Yakov Pechersky]

I don't understand how [A, B].suffix 3 = [] is true though

[Yakov Pechersky]

For any reasonable suffix

[Yakov Pechersky]

I'm thinking python-style

[a, b][-3:]

[Bryan Gin-ge Chen]

Maybe taking the second component of docs#list.split_at is what you want?

[Marcus Rossel]

Bryan Gin-ge Chen said:

Maybe taking the second component of docs#list.split_at is what you want?

That looks promising:

[1, 2, 3, 4].split_at 5 = ([1, 2, 3, 4], [])

[Bryan Gin-ge Chen]

It returns []:

import data.list.defs

#eval (['A','B','C','D','E','F'].split_at 3).snd
-- ['D', 'E', 'F']
#eval (['A','B'].split_at 3).snd
-- []

[Yakov Pechersky]

docs#list.split_at_eq_take_drop

[Yakov Pechersky]

So provably equal to my first definition

[Bryan Gin-ge Chen]

Yep, docs#list.drop is what you want

import data.list.defs

#eval (['A','B','C','D','E','F'].drop 3)
-- ['D', 'E', 'F']
#eval (['A','B'].drop 3)
-- []

[Marcus Rossel]

Ohhh, perfect :)

[Yakov Pechersky]

Oh, you mean suffix 3 as in suffix after removing 3 elements. Yes, that's drop

[Marcus Rossel]

Well I actually meant suffix as _the last n elements_, but drop turns out to work better for my purposes :)