-module(gleam@list). -compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function]). -export([length/1, reverse/1, is_empty/1, contains/2, first/1, rest/1, filter/2, filter_map/2, map/2, map2/3, index_map/2, try_map/2, drop/2, take/2, new/0, append/2, prepend/2, concat/1, flatten/1, flat_map/2, fold/3, group/2, map_fold/3, fold_right/3, index_fold/3, try_fold/3, fold_until/3, find/2, find_map/2, all/2, any/2, zip/2, strict_zip/2, unzip/1, intersperse/2, at/2, unique/1, sort/2, range/2, repeat/2, split/2, split_while/2, key_find/2, key_filter/2, pop/2, pop_map/2, key_pop/2, key_set/3, each/2, try_each/2, partition/2, permutations/1, window/2, window_by_2/1, drop_while/2, take_while/2, chunk/2, sized_chunk/2, reduce/2, scan/3, last/1, combinations/2, combination_pairs/1, transpose/1, interleave/1, shuffle/1]). -export_type([length_mismatch/0, continue_or_stop/1]). -type length_mismatch() :: length_mismatch. -type continue_or_stop(XA) :: {continue, XA} | {stop, XA}. -spec length(list(any())) -> integer(). length(List) -> erlang:length(List). -spec reverse(list(XF)) -> list(XF). reverse(Xs) -> lists:reverse(Xs). -spec is_empty(list(any())) -> boolean(). is_empty(List) -> List =:= []. -spec contains(list(XN), XN) -> boolean(). contains(List, Elem) -> case List of [] -> false; [First | _] when First =:= Elem -> true; [_ | Rest] -> contains(Rest, Elem) end. -spec first(list(XP)) -> {ok, XP} | {error, nil}. first(List) -> case List of [] -> {error, nil}; [X | _] -> {ok, X} end. -spec rest(list(XT)) -> {ok, list(XT)} | {error, nil}. rest(List) -> case List of [] -> {error, nil}; [_ | Xs] -> {ok, Xs} end. -spec update_group(fun((XY) -> XZ)) -> fun((gleam@dict:dict(XZ, list(XY)), XY) -> gleam@dict:dict(XZ, list(XY))). update_group(F) -> fun(Groups, Elem) -> case gleam@dict:get(Groups, F(Elem)) of {ok, Existing} -> gleam@dict:insert(Groups, F(Elem), [Elem | Existing]); {error, _} -> gleam@dict:insert(Groups, F(Elem), [Elem]) end end. -spec do_filter(list(YM), fun((YM) -> boolean()), list(YM)) -> list(YM). do_filter(List, Fun, Acc) -> case List of [] -> reverse(Acc); [X | Xs] -> New_acc = case Fun(X) of true -> [X | Acc]; false -> Acc end, do_filter(Xs, Fun, New_acc) end. -spec filter(list(YQ), fun((YQ) -> boolean())) -> list(YQ). filter(List, Predicate) -> do_filter(List, Predicate, []). -spec do_filter_map(list(YT), fun((YT) -> {ok, YV} | {error, any()}), list(YV)) -> list(YV). do_filter_map(List, Fun, Acc) -> case List of [] -> reverse(Acc); [X | Xs] -> New_acc = case Fun(X) of {ok, X@1} -> [X@1 | Acc]; {error, _} -> Acc end, do_filter_map(Xs, Fun, New_acc) end. -spec filter_map(list(AAB), fun((AAB) -> {ok, AAD} | {error, any()})) -> list(AAD). filter_map(List, Fun) -> do_filter_map(List, Fun, []). -spec do_map(list(AAI), fun((AAI) -> AAK), list(AAK)) -> list(AAK). do_map(List, Fun, Acc) -> case List of [] -> reverse(Acc); [X | Xs] -> do_map(Xs, Fun, [Fun(X) | Acc]) end. -spec map(list(AAN), fun((AAN) -> AAP)) -> list(AAP). map(List, Fun) -> do_map(List, Fun, []). -spec do_map2(list(AAX), list(AAZ), fun((AAX, AAZ) -> ABB), list(ABB)) -> list(ABB). do_map2(List1, List2, Fun, Acc) -> case {List1, List2} of {[], _} -> reverse(Acc); {_, []} -> reverse(Acc); {[A | As_], [B | Bs]} -> do_map2(As_, Bs, Fun, [Fun(A, B) | Acc]) end. -spec map2(list(AAR), list(AAT), fun((AAR, AAT) -> AAV)) -> list(AAV). map2(List1, List2, Fun) -> do_map2(List1, List2, Fun, []). -spec do_index_map( list(ABJ), fun((integer(), ABJ) -> ABL), integer(), list(ABL) ) -> list(ABL). do_index_map(List, Fun, Index, Acc) -> case List of [] -> reverse(Acc); [X | Xs] -> Acc@1 = [Fun(Index, X) | Acc], do_index_map(Xs, Fun, Index + 1, Acc@1) end. -spec index_map(list(ABO), fun((integer(), ABO) -> ABQ)) -> list(ABQ). index_map(List, Fun) -> do_index_map(List, Fun, 0, []). -spec do_try_map(list(ABS), fun((ABS) -> {ok, ABU} | {error, ABV}), list(ABU)) -> {ok, list(ABU)} | {error, ABV}. do_try_map(List, Fun, Acc) -> case List of [] -> {ok, reverse(Acc)}; [X | Xs] -> case Fun(X) of {ok, Y} -> do_try_map(Xs, Fun, [Y | Acc]); {error, Error} -> {error, Error} end end. -spec try_map(list(ACC), fun((ACC) -> {ok, ACE} | {error, ACF})) -> {ok, list(ACE)} | {error, ACF}. try_map(List, Fun) -> do_try_map(List, Fun, []). -spec drop(list(ACL), integer()) -> list(ACL). drop(List, N) -> case N =< 0 of true -> List; false -> case List of [] -> []; [_ | Xs] -> drop(Xs, N - 1) end end. -spec do_take(list(ACO), integer(), list(ACO)) -> list(ACO). do_take(List, N, Acc) -> case N =< 0 of true -> reverse(Acc); false -> case List of [] -> reverse(Acc); [X | Xs] -> do_take(Xs, N - 1, [X | Acc]) end end. -spec take(list(ACS), integer()) -> list(ACS). take(List, N) -> do_take(List, N, []). -spec new() -> list(any()). new() -> []. -spec append(list(ACX), list(ACX)) -> list(ACX). append(First, Second) -> lists:append(First, Second). -spec prepend(list(ADF), ADF) -> list(ADF). prepend(List, Item) -> [Item | List]. -spec reverse_and_prepend(list(ADI), list(ADI)) -> list(ADI). reverse_and_prepend(Prefix, Suffix) -> case Prefix of [] -> Suffix; [First | Rest] -> reverse_and_prepend(Rest, [First | Suffix]) end. -spec do_concat(list(list(ADM)), list(ADM)) -> list(ADM). do_concat(Lists, Acc) -> case Lists of [] -> reverse(Acc); [List | Further_lists] -> do_concat(Further_lists, reverse_and_prepend(List, Acc)) end. -spec concat(list(list(ADR))) -> list(ADR). concat(Lists) -> do_concat(Lists, []). -spec flatten(list(list(ADV))) -> list(ADV). flatten(Lists) -> do_concat(Lists, []). -spec flat_map(list(ADZ), fun((ADZ) -> list(AEB))) -> list(AEB). flat_map(List, Fun) -> _pipe = map(List, Fun), concat(_pipe). -spec fold(list(AEE), AEG, fun((AEG, AEE) -> AEG)) -> AEG. fold(List, Initial, Fun) -> case List of [] -> Initial; [X | Rest] -> fold(Rest, Fun(Initial, X), Fun) end. -spec group(list(YG), fun((YG) -> YI)) -> gleam@dict:dict(YI, list(YG)). group(List, Key) -> fold(List, gleam@dict:new(), update_group(Key)). -spec map_fold(list(ABE), ABG, fun((ABG, ABE) -> {ABG, ABH})) -> {ABG, list(ABH)}. map_fold(List, Acc, Fun) -> _pipe = fold( List, {Acc, []}, fun(Acc@1, Item) -> {Current_acc, Items} = Acc@1, {Next_acc, Next_item} = Fun(Current_acc, Item), {Next_acc, [Next_item | Items]} end ), gleam@pair:map_second(_pipe, fun reverse/1). -spec fold_right(list(AEH), AEJ, fun((AEJ, AEH) -> AEJ)) -> AEJ. fold_right(List, Initial, Fun) -> case List of [] -> Initial; [X | Rest] -> Fun(fold_right(Rest, Initial, Fun), X) end. -spec do_index_fold( list(AEK), AEM, fun((AEM, AEK, integer()) -> AEM), integer() ) -> AEM. do_index_fold(Over, Acc, With, Index) -> case Over of [] -> Acc; [First | Rest] -> do_index_fold(Rest, With(Acc, First, Index), With, Index + 1) end. -spec index_fold(list(AEN), AEP, fun((AEP, AEN, integer()) -> AEP)) -> AEP. index_fold(Over, Initial, Fun) -> do_index_fold(Over, Initial, Fun, 0). -spec try_fold(list(AEQ), AES, fun((AES, AEQ) -> {ok, AES} | {error, AET})) -> {ok, AES} | {error, AET}. try_fold(Collection, Accumulator, Fun) -> case Collection of [] -> {ok, Accumulator}; [First | Rest] -> case Fun(Accumulator, First) of {ok, Result} -> try_fold(Rest, Result, Fun); {error, _} = Error -> Error end end. -spec fold_until(list(AEY), AFA, fun((AFA, AEY) -> continue_or_stop(AFA))) -> AFA. fold_until(Collection, Accumulator, Fun) -> case Collection of [] -> Accumulator; [First | Rest] -> case Fun(Accumulator, First) of {continue, Next_accumulator} -> fold_until(Rest, Next_accumulator, Fun); {stop, B} -> B end end. -spec find(list(AFC), fun((AFC) -> boolean())) -> {ok, AFC} | {error, nil}. find(Haystack, Is_desired) -> case Haystack of [] -> {error, nil}; [X | Rest] -> case Is_desired(X) of true -> {ok, X}; _ -> find(Rest, Is_desired) end end. -spec find_map(list(AFG), fun((AFG) -> {ok, AFI} | {error, any()})) -> {ok, AFI} | {error, nil}. find_map(Haystack, Fun) -> case Haystack of [] -> {error, nil}; [X | Rest] -> case Fun(X) of {ok, X@1} -> {ok, X@1}; _ -> find_map(Rest, Fun) end end. -spec all(list(AFO), fun((AFO) -> boolean())) -> boolean(). all(List, Predicate) -> case List of [] -> true; [First | Rest] -> case Predicate(First) of true -> all(Rest, Predicate); false -> false end end. -spec any(list(AFQ), fun((AFQ) -> boolean())) -> boolean(). any(List, Predicate) -> case List of [] -> false; [First | Rest] -> case Predicate(First) of true -> true; false -> any(Rest, Predicate) end end. -spec do_zip(list(AFS), list(AFU), list({AFS, AFU})) -> list({AFS, AFU}). do_zip(Xs, Ys, Acc) -> case {Xs, Ys} of {[X | Xs@1], [Y | Ys@1]} -> do_zip(Xs@1, Ys@1, [{X, Y} | Acc]); {_, _} -> reverse(Acc) end. -spec zip(list(AFY), list(AGA)) -> list({AFY, AGA}). zip(List, Other) -> do_zip(List, Other, []). -spec strict_zip(list(AGD), list(AGF)) -> {ok, list({AGD, AGF})} | {error, length_mismatch()}. strict_zip(List, Other) -> case length(List) =:= length(Other) of true -> {ok, zip(List, Other)}; false -> {error, length_mismatch} end. -spec do_unzip(list({AVX, AVY}), list(AVX), list(AVY)) -> {list(AVX), list(AVY)}. do_unzip(Input, Xs, Ys) -> case Input of [] -> {reverse(Xs), reverse(Ys)}; [{X, Y} | Rest] -> do_unzip(Rest, [X | Xs], [Y | Ys]) end. -spec unzip(list({AGO, AGP})) -> {list(AGO), list(AGP)}. unzip(Input) -> do_unzip(Input, [], []). -spec do_intersperse(list(AGT), AGT, list(AGT)) -> list(AGT). do_intersperse(List, Separator, Acc) -> case List of [] -> reverse(Acc); [X | Rest] -> do_intersperse(Rest, Separator, [X, Separator | Acc]) end. -spec intersperse(list(AGX), AGX) -> list(AGX). intersperse(List, Elem) -> case List of [] -> List; [_] -> List; [X | Rest] -> do_intersperse(Rest, Elem, [X]) end. -spec at(list(AHA), integer()) -> {ok, AHA} | {error, nil}. at(List, Index) -> case Index >= 0 of true -> _pipe = List, _pipe@1 = drop(_pipe, Index), first(_pipe@1); false -> {error, nil} end. -spec unique(list(AHE)) -> list(AHE). unique(List) -> case List of [] -> []; [X | Rest] -> [X | unique(filter(Rest, fun(Y) -> Y /= X end))] end. -spec merge_up( integer(), integer(), list(AHH), list(AHH), list(AHH), fun((AHH, AHH) -> gleam@order:order()) ) -> list(AHH). merge_up(Na, Nb, A, B, Acc, Compare) -> case {Na, Nb, A, B} of {0, 0, _, _} -> Acc; {_, 0, [Ax | Ar], _} -> merge_up(Na - 1, Nb, Ar, B, [Ax | Acc], Compare); {0, _, _, [Bx | Br]} -> merge_up(Na, Nb - 1, A, Br, [Bx | Acc], Compare); {_, _, [Ax@1 | Ar@1], [Bx@1 | Br@1]} -> case Compare(Ax@1, Bx@1) of gt -> merge_up(Na, Nb - 1, A, Br@1, [Bx@1 | Acc], Compare); _ -> merge_up(Na - 1, Nb, Ar@1, B, [Ax@1 | Acc], Compare) end; {_, _, _, _} -> Acc end. -spec merge_down( integer(), integer(), list(AHM), list(AHM), list(AHM), fun((AHM, AHM) -> gleam@order:order()) ) -> list(AHM). merge_down(Na, Nb, A, B, Acc, Compare) -> case {Na, Nb, A, B} of {0, 0, _, _} -> Acc; {_, 0, [Ax | Ar], _} -> merge_down(Na - 1, Nb, Ar, B, [Ax | Acc], Compare); {0, _, _, [Bx | Br]} -> merge_down(Na, Nb - 1, A, Br, [Bx | Acc], Compare); {_, _, [Ax@1 | Ar@1], [Bx@1 | Br@1]} -> case Compare(Bx@1, Ax@1) of lt -> merge_down(Na - 1, Nb, Ar@1, B, [Ax@1 | Acc], Compare); _ -> merge_down(Na, Nb - 1, A, Br@1, [Bx@1 | Acc], Compare) end; {_, _, _, _} -> Acc end. -spec merge_sort( list(AHR), integer(), fun((AHR, AHR) -> gleam@order:order()), boolean() ) -> list(AHR). merge_sort(L, Ln, Compare, Down) -> N = Ln div 2, A = L, B = drop(L, N), case Ln < 3 of true -> case Down of true -> merge_down(N, Ln - N, A, B, [], Compare); false -> merge_up(N, Ln - N, A, B, [], Compare) end; false -> case Down of true -> merge_down( N, Ln - N, merge_sort(A, N, Compare, false), merge_sort(B, Ln - N, Compare, false), [], Compare ); false -> merge_up( N, Ln - N, merge_sort(A, N, Compare, true), merge_sort(B, Ln - N, Compare, true), [], Compare ) end end. -spec sort(list(AHU), fun((AHU, AHU) -> gleam@order:order())) -> list(AHU). sort(List, Compare) -> merge_sort(List, length(List), Compare, true). -spec tail_recursive_range(integer(), integer(), list(integer())) -> list(integer()). tail_recursive_range(Start, Stop, Acc) -> case gleam@int:compare(Start, Stop) of eq -> [Stop | Acc]; gt -> tail_recursive_range(Start, Stop + 1, [Stop | Acc]); lt -> tail_recursive_range(Start, Stop - 1, [Stop | Acc]) end. -spec range(integer(), integer()) -> list(integer()). range(Start, Stop) -> tail_recursive_range(Start, Stop, []). -spec do_repeat(AIA, integer(), list(AIA)) -> list(AIA). do_repeat(A, Times, Acc) -> case Times =< 0 of true -> Acc; false -> do_repeat(A, Times - 1, [A | Acc]) end. -spec repeat(AID, integer()) -> list(AID). repeat(A, Times) -> do_repeat(A, Times, []). -spec do_split(list(AIF), integer(), list(AIF)) -> {list(AIF), list(AIF)}. do_split(List, N, Taken) -> case N =< 0 of true -> {reverse(Taken), List}; false -> case List of [] -> {reverse(Taken), []}; [X | Xs] -> do_split(Xs, N - 1, [X | Taken]) end end. -spec split(list(AIK), integer()) -> {list(AIK), list(AIK)}. split(List, Index) -> do_split(List, Index, []). -spec do_split_while(list(AIO), fun((AIO) -> boolean()), list(AIO)) -> {list(AIO), list(AIO)}. do_split_while(List, F, Acc) -> case List of [] -> {reverse(Acc), []}; [X | Xs] -> case F(X) of false -> {reverse(Acc), List}; _ -> do_split_while(Xs, F, [X | Acc]) end end. -spec split_while(list(AIT), fun((AIT) -> boolean())) -> {list(AIT), list(AIT)}. split_while(List, Predicate) -> do_split_while(List, Predicate, []). -spec key_find(list({AIX, AIY}), AIX) -> {ok, AIY} | {error, nil}. key_find(Keyword_list, Desired_key) -> find_map( Keyword_list, fun(Keyword) -> {Key, Value} = Keyword, case Key =:= Desired_key of true -> {ok, Value}; false -> {error, nil} end end ). -spec key_filter(list({AJC, AJD}), AJC) -> list(AJD). key_filter(Keyword_list, Desired_key) -> filter_map( Keyword_list, fun(Keyword) -> {Key, Value} = Keyword, case Key =:= Desired_key of true -> {ok, Value}; false -> {error, nil} end end ). -spec do_pop(list(AZQ), fun((AZQ) -> boolean()), list(AZQ)) -> {ok, {AZQ, list(AZQ)}} | {error, nil}. do_pop(Haystack, Predicate, Checked) -> case Haystack of [] -> {error, nil}; [X | Rest] -> case Predicate(X) of true -> {ok, {X, append(reverse(Checked), Rest)}}; false -> do_pop(Rest, Predicate, [X | Checked]) end end. -spec pop(list(AJK), fun((AJK) -> boolean())) -> {ok, {AJK, list(AJK)}} | {error, nil}. pop(Haystack, Is_desired) -> do_pop(Haystack, Is_desired, []). -spec do_pop_map(list(BAE), fun((BAE) -> {ok, BAR} | {error, any()}), list(BAE)) -> {ok, {BAR, list(BAE)}} | {error, nil}. do_pop_map(Haystack, Mapper, Checked) -> case Haystack of [] -> {error, nil}; [X | Rest] -> case Mapper(X) of {ok, Y} -> {ok, {Y, append(reverse(Checked), Rest)}}; {error, _} -> do_pop_map(Rest, Mapper, [X | Checked]) end end. -spec pop_map(list(AJT), fun((AJT) -> {ok, AJV} | {error, any()})) -> {ok, {AJV, list(AJT)}} | {error, nil}. pop_map(Haystack, Is_desired) -> do_pop_map(Haystack, Is_desired, []). -spec key_pop(list({AKC, AKD}), AKC) -> {ok, {AKD, list({AKC, AKD})}} | {error, nil}. key_pop(Haystack, Key) -> pop_map( Haystack, fun(Entry) -> {K, V} = Entry, case K of K@1 when K@1 =:= Key -> {ok, V}; _ -> {error, nil} end end ). -spec key_set(list({AKI, AKJ}), AKI, AKJ) -> list({AKI, AKJ}). key_set(List, Key, Value) -> case List of [] -> [{Key, Value}]; [{K, _} | Rest] when K =:= Key -> [{Key, Value} | Rest]; [First | Rest@1] -> [First | key_set(Rest@1, Key, Value)] end. -spec each(list(AKM), fun((AKM) -> any())) -> nil. each(List, F) -> case List of [] -> nil; [X | Xs] -> F(X), each(Xs, F) end. -spec try_each(list(AKP), fun((AKP) -> {ok, any()} | {error, AKS})) -> {ok, nil} | {error, AKS}. try_each(List, Fun) -> case List of [] -> {ok, nil}; [X | Xs] -> case Fun(X) of {ok, _} -> try_each(Xs, Fun); {error, E} -> {error, E} end end. -spec do_partition(list(BBY), fun((BBY) -> boolean()), list(BBY), list(BBY)) -> {list(BBY), list(BBY)}. do_partition(List, Categorise, Trues, Falses) -> case List of [] -> {reverse(Trues), reverse(Falses)}; [X | Xs] -> case Categorise(X) of true -> do_partition(Xs, Categorise, [X | Trues], Falses); false -> do_partition(Xs, Categorise, Trues, [X | Falses]) end end. -spec partition(list(ALC), fun((ALC) -> boolean())) -> {list(ALC), list(ALC)}. partition(List, Categorise) -> do_partition(List, Categorise, [], []). -spec permutations(list(ALG)) -> list(list(ALG)). permutations(L) -> case L of [] -> [[]]; _ -> _pipe = L, _pipe@5 = index_map(_pipe, fun(I_idx, I) -> _pipe@1 = L, _pipe@2 = index_fold( _pipe@1, [], fun(Acc, J, J_idx) -> case I_idx =:= J_idx of true -> Acc; false -> [J | Acc] end end ), _pipe@3 = reverse(_pipe@2), _pipe@4 = permutations(_pipe@3), map(_pipe@4, fun(Permutation) -> [I | Permutation] end) end), concat(_pipe@5) end. -spec do_window(list(list(ALK)), list(ALK), integer()) -> list(list(ALK)). do_window(Acc, L, N) -> Window = take(L, N), case length(Window) =:= N of true -> do_window([Window | Acc], drop(L, 1), N); false -> Acc end. -spec window(list(ALQ), integer()) -> list(list(ALQ)). window(L, N) -> _pipe = do_window([], L, N), reverse(_pipe). -spec window_by_2(list(ALU)) -> list({ALU, ALU}). window_by_2(L) -> zip(L, drop(L, 1)). -spec drop_while(list(ALX), fun((ALX) -> boolean())) -> list(ALX). drop_while(List, Predicate) -> case List of [] -> []; [X | Xs] -> case Predicate(X) of true -> drop_while(Xs, Predicate); false -> [X | Xs] end end. -spec do_take_while(list(AMA), fun((AMA) -> boolean()), list(AMA)) -> list(AMA). do_take_while(List, Predicate, Acc) -> case List of [] -> reverse(Acc); [First | Rest] -> case Predicate(First) of true -> do_take_while(Rest, Predicate, [First | Acc]); false -> reverse(Acc) end end. -spec take_while(list(AME), fun((AME) -> boolean())) -> list(AME). take_while(List, Predicate) -> do_take_while(List, Predicate, []). -spec do_chunk(list(AMH), fun((AMH) -> AMJ), AMJ, list(AMH), list(list(AMH))) -> list(list(AMH)). do_chunk(List, F, Previous_key, Current_chunk, Acc) -> case List of [First | Rest] -> Key = F(First), case Key =:= Previous_key of false -> New_acc = [reverse(Current_chunk) | Acc], do_chunk(Rest, F, Key, [First], New_acc); _ -> do_chunk(Rest, F, Key, [First | Current_chunk], Acc) end; _ -> reverse([reverse(Current_chunk) | Acc]) end. -spec chunk(list(AMP), fun((AMP) -> any())) -> list(list(AMP)). chunk(List, F) -> case List of [] -> []; [First | Rest] -> do_chunk(Rest, F, F(First), [First], []) end. -spec do_sized_chunk( list(AMU), integer(), integer(), list(AMU), list(list(AMU)) ) -> list(list(AMU)). do_sized_chunk(List, Count, Left, Current_chunk, Acc) -> case List of [] -> case Current_chunk of [] -> reverse(Acc); Remaining -> reverse([reverse(Remaining) | Acc]) end; [First | Rest] -> Chunk = [First | Current_chunk], case Left > 1 of false -> do_sized_chunk( Rest, Count, Count, [], [reverse(Chunk) | Acc] ); true -> do_sized_chunk(Rest, Count, Left - 1, Chunk, Acc) end end. -spec sized_chunk(list(ANB), integer()) -> list(list(ANB)). sized_chunk(List, Count) -> do_sized_chunk(List, Count, Count, [], []). -spec reduce(list(ANF), fun((ANF, ANF) -> ANF)) -> {ok, ANF} | {error, nil}. reduce(List, Fun) -> case List of [] -> {error, nil}; [First | Rest] -> {ok, fold(Rest, First, Fun)} end. -spec do_scan(list(ANJ), ANL, list(ANL), fun((ANL, ANJ) -> ANL)) -> list(ANL). do_scan(List, Accumulator, Accumulated, Fun) -> case List of [] -> reverse(Accumulated); [X | Xs] -> Next = Fun(Accumulator, X), do_scan(Xs, Next, [Next | Accumulated], Fun) end. -spec scan(list(ANO), ANQ, fun((ANQ, ANO) -> ANQ)) -> list(ANQ). scan(List, Initial, Fun) -> do_scan(List, Initial, [], Fun). -spec last(list(ANS)) -> {ok, ANS} | {error, nil}. last(List) -> _pipe = List, reduce(_pipe, fun(_, Elem) -> Elem end). -spec combinations(list(ANW), integer()) -> list(list(ANW)). combinations(Items, N) -> case N of 0 -> [[]]; _ -> case Items of [] -> []; [X | Xs] -> First_combinations = begin _pipe = map( combinations(Xs, N - 1), fun(Com) -> [X | Com] end ), reverse(_pipe) end, fold( First_combinations, combinations(Xs, N), fun(Acc, C) -> [C | Acc] end ) end end. -spec do_combination_pairs(list(AOA)) -> list(list({AOA, AOA})). do_combination_pairs(Items) -> case Items of [] -> []; [X | Xs] -> First_combinations = map(Xs, fun(Other) -> {X, Other} end), [First_combinations | do_combination_pairs(Xs)] end. -spec combination_pairs(list(AOE)) -> list({AOE, AOE}). combination_pairs(Items) -> _pipe = do_combination_pairs(Items), concat(_pipe). -spec transpose(list(list(AOL))) -> list(list(AOL)). transpose(List_of_list) -> Take_first = fun(List) -> case List of [] -> []; [F] -> [F]; [F@1 | _] -> [F@1] end end, case List_of_list of [] -> []; [[] | Xss] -> transpose(Xss); Rows -> Firsts = begin _pipe = Rows, _pipe@1 = map(_pipe, Take_first), concat(_pipe@1) end, Rest = transpose(map(Rows, fun(_capture) -> drop(_capture, 1) end)), [Firsts | Rest] end. -spec interleave(list(list(AOH))) -> list(AOH). interleave(List) -> _pipe = transpose(List), concat(_pipe). -spec do_shuffle_pair_unwrap(list({float(), AOQ}), list(AOQ)) -> list(AOQ). do_shuffle_pair_unwrap(List, Acc) -> case List of [] -> Acc; [Elem_pair | Enumerable] -> do_shuffle_pair_unwrap( Enumerable, [erlang:element(2, Elem_pair) | Acc] ) end. -spec do_shuffle_by_pair_indexes(list({float(), AOU})) -> list({float(), AOU}). do_shuffle_by_pair_indexes(List_of_pairs) -> sort( List_of_pairs, fun(A_pair, B_pair) -> gleam@float:compare( erlang:element(1, A_pair), erlang:element(1, B_pair) ) end ). -spec shuffle(list(AOX)) -> list(AOX). shuffle(List) -> _pipe = List, _pipe@1 = fold( _pipe, [], fun(Acc, A) -> [{gleam@float:random(+0.0, 1.0), A} | Acc] end ), _pipe@2 = do_shuffle_by_pair_indexes(_pipe@1), do_shuffle_pair_unwrap(_pipe@2, []).