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gleam_stdlib src gleam@queue.erl
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src/gleam@queue.erl

-module(gleam@queue).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).
-export([new/0, from_list/1, to_list/1, is_empty/1, length/1, push_back/2, push_front/2, pop_back/1, pop_front/1, reverse/1, is_logically_equal/3, is_equal/2]).
-export_type([queue/1]).
-opaque queue(EYB) :: {queue, list(EYB), list(EYB)}.
-spec new() -> queue(any()).
new() ->
{queue, [], []}.
-spec from_list(list(EYE)) -> queue(EYE).
from_list(List) ->
{queue, [], List}.
-spec to_list(queue(EYH)) -> list(EYH).
to_list(Queue) ->
_pipe = erlang:element(3, Queue),
lists:append(_pipe, lists:reverse(erlang:element(2, Queue))).
-spec is_empty(queue(any())) -> boolean().
is_empty(Queue) ->
(erlang:element(2, Queue) =:= []) andalso (erlang:element(3, Queue) =:= []).
-spec length(queue(any())) -> integer().
length(Queue) ->
erlang:length(erlang:element(2, Queue)) + erlang:length(
erlang:element(3, Queue)
).
-spec push_back(queue(EYO), EYO) -> queue(EYO).
push_back(Queue, Item) ->
{queue, [Item | erlang:element(2, Queue)], erlang:element(3, Queue)}.
-spec push_front(queue(EYR), EYR) -> queue(EYR).
push_front(Queue, Item) ->
{queue, erlang:element(2, Queue), [Item | erlang:element(3, Queue)]}.
-spec pop_back(queue(EYU)) -> {ok, {EYU, queue(EYU)}} | {error, nil}.
pop_back(Queue) ->
case Queue of
{queue, [], []} ->
{error, nil};
{queue, [], Out} ->
pop_back({queue, lists:reverse(Out), []});
{queue, [First | Rest], Out@1} ->
Queue@1 = {queue, Rest, Out@1},
{ok, {First, Queue@1}}
end.
-spec pop_front(queue(EYZ)) -> {ok, {EYZ, queue(EYZ)}} | {error, nil}.
pop_front(Queue) ->
case Queue of
{queue, [], []} ->
{error, nil};
{queue, In, []} ->
pop_front({queue, [], lists:reverse(In)});
{queue, In@1, [First | Rest]} ->
Queue@1 = {queue, In@1, Rest},
{ok, {First, Queue@1}}
end.
-spec reverse(queue(EZE)) -> queue(EZE).
reverse(Queue) ->
{queue, erlang:element(3, Queue), erlang:element(2, Queue)}.
-spec check_equal(
list(EZH),
list(EZH),
list(EZH),
list(EZH),
fun((EZH, EZH) -> boolean())
) -> boolean().
check_equal(Xs, X_tail, Ys, Y_tail, Eq) ->
case {Xs, X_tail, Ys, Y_tail} of
{[], [], [], []} ->
true;
{[X | Xs@1], _, [Y | Ys@1], _} ->
case Eq(X, Y) of
false ->
false;
true ->
check_equal(Xs@1, X_tail, Ys@1, Y_tail, Eq)
end;
{[], [_ | _], _, _} ->
check_equal(lists:reverse(X_tail), [], Ys, Y_tail, Eq);
{_, _, [], [_ | _]} ->
check_equal(Xs, X_tail, lists:reverse(Y_tail), [], Eq);
{_, _, _, _} ->
false
end.
-spec is_logically_equal(queue(EZM), queue(EZM), fun((EZM, EZM) -> boolean())) -> boolean().
is_logically_equal(A, B, Element_is_equal) ->
check_equal(
erlang:element(3, A),
erlang:element(2, A),
erlang:element(3, B),
erlang:element(2, B),
Element_is_equal
).
-spec is_equal(queue(EZP), queue(EZP)) -> boolean().
is_equal(A, B) ->
check_equal(
erlang:element(3, A),
erlang:element(2, A),
erlang:element(3, B),
erlang:element(2, B),
fun(A@1, B@1) -> A@1 =:= B@1 end
).