take.erl

-module(take).
-export([take/2]).
-export([take_test/0]).

-spec take(integer(), [T]) -> [T].
take(_, []) -> [];
take(0, _) -> [];
take(N, L) -> take(N, L, []).

take(_, [], Ac) -> lists:reverse(Ac);
take(0, _, Ac) -> lists:reverse(Ac);
take(N, [H|T], Ac) -> take(N-1, T, [H|Ac]).

take_test() ->
  [] = take(0, "hello"),
  "hell" = take(4, "hello"),
  "hello" = take(5, "hello"),
  "hello" = take(9, "hello"),
  passed.

Nice tests!

Thinking about your comment on tests for the previous gists I played a little with this one and, interestingly, take(-2, "hello") still works as expected... though I'm not sure why 😅

One thing I missed before was a subtle error on your specs…
integer is the type of the atom integer.
integer() is the type of all integer numbers.

Fixed 👍