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gleam_stdlib
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retired
A standard library for the Gleam programming language
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Files
src/gleam@list.erl
-module(gleam@list).
-compile(no_auto_import).
-export([length/1, reverse/1, is_empty/1, contains/2, first/1, rest/1, filter/2, filter_map/2, map/2, map_fold/3, index_map/2, try_map/2, drop/2, take/2, new/0, append/2, prepend/2, flatten/1, flat_map/2, 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, pop/2, pop_map/2, key_pop/2, key_set/3, 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, interleave/1, transpose/1]).
-export_type([length_mismatch/0, continue_or_stop/1]).
-type length_mismatch() :: length_mismatch.
-type continue_or_stop(HT) :: {continue, HT} | {stop, HT}.
-spec length(list(any())) -> integer().
length(List) ->
erlang:length(List).
-spec reverse(list(HY)) -> list(HY).
reverse(Xs) ->
lists:reverse(Xs).
-spec is_empty(list(any())) -> boolean().
is_empty(List) ->
List =:= [].
-spec contains(list(IG), IG) -> boolean().
contains(List, Elem) ->
case List of
[] ->
false;
[Head | Rest] ->
(Head =:= Elem) orelse contains(Rest, Elem)
end.
-spec first(list(II)) -> {ok, II} | {error, nil}.
first(List) ->
case List of
[] ->
{error, nil};
[X | _@1] ->
{ok, X}
end.
-spec rest(list(IM)) -> {ok, list(IM)} | {error, nil}.
rest(List) ->
case List of
[] ->
{error, nil};
[_@1 | Xs] ->
{ok, Xs}
end.
-spec do_filter(list(IR), fun((IR) -> boolean()), list(IR)) -> list(IR).
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(IV), fun((IV) -> boolean())) -> list(IV).
filter(List, Predicate) ->
do_filter(List, Predicate, []).
-spec do_filter_map(list(IY), fun((IY) -> {ok, JA} | {error, any()}), list(JA)) -> list(JA).
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, _@1} ->
Acc
end,
do_filter_map(Xs, Fun, New_acc)
end.
-spec filter_map(list(JG), fun((JG) -> {ok, JI} | {error, any()})) -> list(JI).
filter_map(List, Fun) ->
do_filter_map(List, Fun, []).
-spec do_map(list(JN), fun((JN) -> JP), list(JP)) -> list(JP).
do_map(List, Fun, Acc) ->
case List of
[] ->
reverse(Acc);
[X | Xs] ->
do_map(Xs, Fun, [Fun(X) | Acc])
end.
-spec map(list(JS), fun((JS) -> JU)) -> list(JU).
map(List, Fun) ->
do_map(List, Fun, []).
-spec map_fold(list(JW), JY, fun((JY, JW) -> {JY, JZ})) -> {JY, list(JZ)}.
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 do_index_map(list(KB), fun((integer(), KB) -> KD), integer(), list(KD)) -> list(KD).
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(KG), fun((integer(), KG) -> KI)) -> list(KI).
index_map(List, Fun) ->
do_index_map(List, Fun, 0, []).
-spec do_try_map(list(KK), fun((KK) -> {ok, KM} | {error, KN}), list(KM)) -> {ok,
list(KM)} |
{error, KN}.
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(KU), fun((KU) -> {ok, KW} | {error, KX})) -> {ok, list(KW)} |
{error, KX}.
try_map(List, Fun) ->
do_try_map(List, Fun, []).
-spec drop(list(LD), integer()) -> list(LD).
drop(List, N) ->
case N =< 0 of
true ->
List;
false ->
case List of
[] ->
[];
[_@1 | Xs] ->
drop(Xs, N - 1)
end
end.
-spec do_take(list(LG), integer(), list(LG)) -> list(LG).
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(LK), integer()) -> list(LK).
take(List, N) ->
do_take(List, N, []).
-spec new() -> list(any()).
new() ->
[].
-spec append(list(LP), list(LP)) -> list(LP).
append(First, Second) ->
lists:append(First, Second).
-spec prepend(list(LX), LX) -> list(LX).
prepend(List, Item) ->
[Item | List].
-spec do_flatten(list(list(MA)), list(MA)) -> list(MA).
do_flatten(Lists, Acc) ->
case Lists of
[] ->
Acc;
[L | Rest] ->
do_flatten(Rest, append(Acc, L))
end.
-spec flatten(list(list(MF))) -> list(MF).
flatten(Lists) ->
do_flatten(Lists, []).
-spec flat_map(list(MJ), fun((MJ) -> list(ML))) -> list(ML).
flat_map(List, Fun) ->
_pipe = map(List, Fun),
flatten(_pipe).
-spec fold(list(MO), MQ, fun((MQ, MO) -> MQ)) -> MQ.
fold(List, Initial, Fun) ->
case List of
[] ->
Initial;
[X | Rest] ->
fold(Rest, Fun(Initial, X), Fun)
end.
-spec fold_right(list(MR), MT, fun((MT, MR) -> MT)) -> MT.
fold_right(List, Initial, Fun) ->
case List of
[] ->
Initial;
[X | Rest] ->
Fun(fold_right(Rest, Initial, Fun), X)
end.
-spec do_index_fold(list(MU), MW, fun((MW, MU, integer()) -> MW), integer()) -> MW.
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(MX), MZ, fun((MZ, MX, integer()) -> MZ)) -> MZ.
index_fold(Over, Initial, Fun) ->
do_index_fold(Over, Initial, Fun, 0).
-spec try_fold(list(NA), NC, fun((NC, NA) -> {ok, NC} | {error, ND})) -> {ok,
NC} |
{error, ND}.
try_fold(Collection, Accumulator, Fun) ->
case Collection of
[] ->
{ok, Accumulator};
[First | Rest] ->
case Fun(Accumulator, First) of
{error, _try} -> {error, _try};
{ok, Accumulator@1} ->
try_fold(Rest, Accumulator@1, Fun)
end
end.
-spec fold_until(list(NI), NK, fun((NK, NI) -> continue_or_stop(NK))) -> NK.
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(NM), fun((NM) -> boolean())) -> {ok, NM} | {error, nil}.
find(Haystack, Is_desired) ->
case Haystack of
[] ->
{error, nil};
[X | Rest] ->
case Is_desired(X) of
true ->
{ok, X};
_@1 ->
find(Rest, Is_desired)
end
end.
-spec find_map(list(NQ), fun((NQ) -> {ok, NS} | {error, any()})) -> {ok, NS} |
{error, nil}.
find_map(Haystack, Fun) ->
case Haystack of
[] ->
{error, nil};
[X | Rest] ->
case Fun(X) of
{ok, X@1} ->
{ok, X@1};
_@1 ->
find_map(Rest, Fun)
end
end.
-spec all(list(NY), fun((NY) -> boolean())) -> boolean().
all(List, Predicate) ->
case List of
[] ->
true;
[X | Rest] ->
Predicate(X) andalso all(Rest, Predicate)
end.
-spec any(list(OA), fun((OA) -> boolean())) -> boolean().
any(List, Predicate) ->
case List of
[] ->
false;
[X | Rest] ->
Predicate(X) orelse any(Rest, Predicate)
end.
-spec do_zip(list(OC), list(OE), list({OC, OE})) -> list({OC, OE}).
do_zip(Xs, Ys, Acc) ->
case {Xs, Ys} of
{[X | Xs@1], [Y | Ys@1]} ->
do_zip(Xs@1, Ys@1, [{X, Y} | Acc]);
{_@1, _@2} ->
reverse(Acc)
end.
-spec zip(list(OI), list(OK)) -> list({OI, OK}).
zip(Xs, Ys) ->
do_zip(Xs, Ys, []).
-spec strict_zip(list(ON), list(OP)) -> {ok, list({ON, OP})} |
{error, length_mismatch()}.
strict_zip(L1, L2) ->
case length(L1) =:= length(L2) of
true ->
{ok, zip(L1, L2)};
false ->
{error, length_mismatch}
end.
-spec do_unzip(list({OY, OZ}), list(OY), list(OZ)) -> {list(OY), list(OZ)}.
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({OY, OZ})) -> {list(OY), list(OZ)}.
unzip(Input) ->
do_unzip(Input, [], []).
-spec do_intersperse(list(PD), PD, list(PD)) -> list(PD).
do_intersperse(List, Separator, Acc) ->
case List of
[] ->
reverse(Acc);
[X | Rest] ->
do_intersperse(Rest, Separator, [X, Separator | Acc])
end.
-spec intersperse(list(PH), PH) -> list(PH).
intersperse(List, Elem) ->
case List of
[] ->
List;
[_@1] ->
List;
[X | Rest] ->
do_intersperse(Rest, Elem, [X])
end.
-spec at(list(PK), integer()) -> {ok, PK} | {error, nil}.
at(List, Index) ->
_pipe = List,
_pipe@1 = drop(_pipe, Index),
first(_pipe@1).
-spec unique(list(PO)) -> list(PO).
unique(List) ->
case List of
[] ->
[];
[X | Rest] ->
[X | unique(filter(Rest, fun(Y) -> Y /= X end))]
end.
-spec merge_sort(list(PR), list(PR), fun((PR, PR) -> gleam@order:order())) -> list(PR).
merge_sort(A, B, Compare) ->
case {A, B} of
{[], _@1} ->
B;
{_@2, []} ->
A;
{[Ax | Ar], [Bx | Br]} ->
case Compare(Ax, Bx) of
lt ->
[Ax | merge_sort(Ar, B, Compare)];
_@3 ->
[Bx | merge_sort(A, Br, Compare)]
end
end.
-spec do_sort(list(PV), fun((PV, PV) -> gleam@order:order()), integer()) -> list(PV).
do_sort(List, Compare, List_length) ->
case List_length < 2 of
true ->
List;
false ->
Split_length = List_length div 2,
A_list = take(List, Split_length),
B_list = drop(List, Split_length),
merge_sort(
do_sort(A_list, Compare, Split_length),
do_sort(B_list, Compare, List_length - Split_length),
Compare
)
end.
-spec sort(list(PY), fun((PY, PY) -> gleam@order:order())) -> list(PY).
sort(List, Compare) ->
do_sort(List, Compare, length(List)).
-spec range(integer(), integer()) -> list(integer()).
range(Start, Stop) ->
case gleam@int:compare(Start, Stop) of
eq ->
[];
gt ->
[Start | range(Start - 1, Stop)];
lt ->
[Start | range(Start + 1, Stop)]
end.
-spec do_repeat(QC, integer(), list(QC)) -> list(QC).
do_repeat(A, Times, Acc) ->
case Times =< 0 of
true ->
Acc;
false ->
do_repeat(A, Times - 1, [A | Acc])
end.
-spec repeat(QF, integer()) -> list(QF).
repeat(A, Times) ->
do_repeat(A, Times, []).
-spec do_split(list(QH), integer(), list(QH)) -> {list(QH), list(QH)}.
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(QM), integer()) -> {list(QM), list(QM)}.
split(List, Index) ->
do_split(List, Index, []).
-spec do_split_while(list(QQ), fun((QQ) -> boolean()), list(QQ)) -> {list(QQ),
list(QQ)}.
do_split_while(List, F, Acc) ->
case List of
[] ->
{reverse(Acc), []};
[X | Xs] ->
case F(X) of
false ->
{reverse(Acc), List};
_@1 ->
do_split_while(Xs, F, [X | Acc])
end
end.
-spec split_while(list(QV), fun((QV) -> boolean())) -> {list(QV), list(QV)}.
split_while(List, Predicate) ->
do_split_while(List, Predicate, []).
-spec key_find(list({QZ, RA}), QZ) -> {ok, RA} | {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 do_pop(list(RI), fun((RI) -> boolean()), list(RI)) -> {ok, {RI, list(RI)}} |
{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(RI), fun((RI) -> boolean())) -> {ok, {RI, list(RI)}} |
{error, nil}.
pop(Haystack, Is_desired) ->
do_pop(Haystack, Is_desired, []).
-spec do_pop_map(list(RR), fun((RR) -> {ok, RT} | {error, any()}), list(RR)) -> {ok,
{RT,
list(RR)}} |
{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, _@1} ->
do_pop_map(Rest, Mapper, [X | Checked])
end
end.
-spec pop_map(list(RR), fun((RR) -> {ok, RT} | {error, any()})) -> {ok,
{RT,
list(RR)}} |
{error, nil}.
pop_map(Haystack, Is_desired) ->
do_pop_map(Haystack, Is_desired, []).
-spec key_pop(list({SA, SB}), SA) -> {ok, {SB, list({SA, SB})}} | {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};
_@1 ->
{error, nil}
end
end
).
-spec key_set(list({SG, SH}), SG, SH) -> list({SG, SH}).
key_set(List, Key, Value) ->
case List of
[] ->
[{Key, Value}];
[{K, _@1} | Rest] when K =:= Key ->
[{Key, Value} | Rest];
[First | Rest@1] ->
[First | key_set(Rest@1, Key, Value)]
end.
-spec each(list(SK), fun((SK) -> any())) -> nil.
each(List, F) ->
case List of
[] ->
nil;
[X | Xs] ->
F(X),
each(Xs, F)
end.
-spec do_partition(list(SS), fun((SS) -> boolean()), list(SS), list(SS)) -> {list(SS),
list(SS)}.
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(SS), fun((SS) -> boolean())) -> {list(SS), list(SS)}.
partition(List, Categorise) ->
do_partition(List, Categorise, [], []).
-spec permutations(list(SW)) -> list(list(SW)).
permutations(L) ->
case L of
[] ->
[[]];
_@1 ->
_pipe@2 = map(
L,
fun(X) ->
_pipe = filter(L, fun(Y) -> Y /= X end),
_pipe@1 = permutations(_pipe),
map(_pipe@1, fun(_capture) -> append([X], _capture) end)
end
),
flatten(_pipe@2)
end.
-spec do_window(list(list(TA)), list(TA), integer()) -> list(list(TA)).
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(TG), integer()) -> list(list(TG)).
window(L, N) ->
_pipe = do_window([], L, N),
reverse(_pipe).
-spec window_by_2(list(TK)) -> list({TK, TK}).
window_by_2(L) ->
zip(L, drop(L, 1)).
-spec drop_while(list(TN), fun((TN) -> boolean())) -> list(TN).
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(TQ), fun((TQ) -> boolean()), list(TQ)) -> list(TQ).
do_take_while(List, Predicate, Acc) ->
case List of
[] ->
reverse(Acc);
[Head | Tail] ->
case Predicate(Head) of
true ->
do_take_while(Tail, Predicate, [Head | Acc]);
false ->
reverse(Acc)
end
end.
-spec take_while(list(TU), fun((TU) -> boolean())) -> list(TU).
take_while(List, Predicate) ->
do_take_while(List, Predicate, []).
-spec do_chunk(list(TX), fun((TX) -> TZ), TZ, list(TX), list(list(TX))) -> list(list(TX)).
do_chunk(List, F, Previous_key, Current_chunk, Acc) ->
case List of
[Head | Tail] ->
Key = F(Head),
case Key =:= Previous_key of
false ->
New_acc = [reverse(Current_chunk) | Acc],
do_chunk(Tail, F, Key, [Head], New_acc);
_@1 ->
do_chunk(Tail, F, Key, [Head | Current_chunk], Acc)
end;
_@2 ->
reverse([reverse(Current_chunk) | Acc])
end.
-spec chunk(list(UF), fun((UF) -> any())) -> list(list(UF)).
chunk(List, F) ->
case List of
[] ->
[];
[Head | Tail] ->
do_chunk(Tail, F, F(Head), [Head], [])
end.
-spec do_sized_chunk(list(UK), integer(), integer(), list(UK), list(list(UK))) -> list(list(UK)).
do_sized_chunk(List, Count, Left, Current_chunk, Acc) ->
case List of
[] ->
case Current_chunk of
[] ->
reverse(Acc);
Remaining ->
reverse([reverse(Remaining) | Acc])
end;
[Head | Tail] ->
Chunk = [Head | Current_chunk],
case Left > 1 of
false ->
do_sized_chunk(
Tail,
Count,
Count,
[],
[reverse(Chunk) | Acc]
);
true ->
do_sized_chunk(Tail, Count, Left - 1, Chunk, Acc)
end
end.
-spec sized_chunk(list(UR), integer()) -> list(list(UR)).
sized_chunk(List, Count) ->
do_sized_chunk(List, Count, Count, [], []).
-spec reduce(list(UV), fun((UV, UV) -> UV)) -> {ok, UV} | {error, nil}.
reduce(List, Fun) ->
case List of
[] ->
{error, nil};
[Head | Tail] ->
{ok, fold(Tail, Head, Fun)}
end.
-spec do_scan(list(UZ), VB, list(VB), fun((VB, UZ) -> VB)) -> list(VB).
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(VE), VG, fun((VG, VE) -> VG)) -> list(VG).
scan(List, Initial, Fun) ->
do_scan(List, Initial, [], Fun).
-spec last(list(VI)) -> {ok, VI} | {error, nil}.
last(List) ->
_pipe = List,
reduce(_pipe, fun(_, Elem) -> Elem end).
-spec combinations(list(VM), integer()) -> list(list(VM)).
combinations(Items, N) ->
case N of
0 ->
[[]];
_@1 ->
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(VQ)) -> list(list({VQ, VQ})).
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(VU)) -> list({VU, VU}).
combination_pairs(Items) ->
_pipe = do_combination_pairs(Items),
flatten(_pipe).
-spec interleave(list(list(VX))) -> list(VX).
interleave(List) ->
_pipe = transpose(List),
flatten(_pipe).
-spec transpose(list(list(WB))) -> list(list(WB)).
transpose(List_of_list) ->
Take_first = fun(List) -> case List of
[] ->
[];
[F] ->
[F];
[F@1 | _@1] ->
[F@1]
end end,
case List_of_list of
[] ->
[];
[[] | Xss] ->
transpose(Xss);
Rows ->
Firsts = begin
_pipe = Rows,
_pipe@1 = map(_pipe, Take_first),
flatten(_pipe@1)
end,
Rest = transpose(map(Rows, fun(_capture) -> drop(_capture, 1) end)),
[Firsts | Rest]
end.