-module(lookup).

-export([by_key/2]).

by_key(_, []) -> "unknown";
by_key(Key, [{Key, Val} | _]) -> Val;
by_key(Key, [_ | Tail]) -> by_key(Key, Tail).

% lookup:by_key(birthday, [{ice, "cream"}, {birthday, "cake"}]).
% equivalent to proplists:get_value/2_