Caps = string:join(lists:map(fun(S) -> to_caps(S) end, string:tokens("man OF stEEL", " ")), " "),

-module(caps).
-export([start/0]).

to_caps([H|T]) -> [string:to_upper(H)|string:to_lower(T)].

start() ->

Caps = string:join(lists:map(fun(S) -> to_caps(S) end, string:tokens("man OF stEEL", " ")), " "),

io:format("~s~n", [Caps]).