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-module(lqueue).
-compile([export_all]).
-define(QUEUE, queue).
new() -> {0, ?QUEUE:new()}.
is_empty({0, _Q}) ->
true;
is_empty(_) ->
false.
in(V, {L, Q}) -> {L+1, ?QUEUE:in(V, Q)}.
in_r(V, {L, Q}) -> {L+1, ?QUEUE:in_r(V, Q)}.
out({0, _Q} = Q) ->
{empty, Q};
out({L, Q}) ->
{Result, Q1} = ?QUEUE:out(Q),
{Result, {L-1, Q1}}.
out_r({0, _Q} = Q) ->
{empty, Q};
out_r({L, Q}) ->
{Result, Q1} = ?QUEUE:out_r(Q),
{Result, {L-1, Q1}}.
join({L1, Q1}, {L2, Q2}) ->
{L1 + L2, ?QUEUE:join(Q1, Q2)}.
to_list({_L, Q}) ->
?QUEUE:to_list(Q).
from_list(L) ->
{length(L), ?QUEUE:from_list(L)}.
queue_fold(Fun, Init, Q) ->
case out(Q) of
{empty, _Q} -> Init;
{{value, V}, Q1} -> queue_fold(Fun, Fun(V, Init), Q1)
end.
len({L, _Q}) ->
L.
|
