Some examples of simple functions in Erlang

task.erl

-module(task).
-export([words_count/1, count/1, check/1]).

words_count(S) -> iter(0, false, S).

iter(W, _    , []         ) -> W;
iter(W, _    , [32 | Tail]) -> iter(W    , false, Tail);
iter(W, false, [_  | Tail]) -> iter(W + 1, true , Tail);
iter(W, _    , [_  | Tail]) -> iter(W    , true , Tail).

count(10) -> [10];
count(T ) -> [T | count(T + 1)].

check(success) -> "success";
check({error, Message}) -> "error: " ++ Message.