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-module(tuple).
-compile(no_auto_import).
-export([new/2, first/1, second/1, swap/1, fetch/2]).
new(A, B) ->
{A, B}.
first(Tup) ->
{A, _} = Tup,
A.
second(Tup) ->
{_, A} = Tup,
A.
swap(Tup) ->
{A, B} = Tup,
{B, A}.
fetch(Haystack, Needle) ->
list:find(Haystack, fun(Tuple) -> case first(Tuple) =:= Needle of
true ->
{ok, second(Tuple)};
false ->
{error, []}
end end).
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