-module(gleeps@stdlib@list).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/gleeps/stdlib/list.gleam").
-export([length/1, count/2, reverse/1, is_empty/1, contains/2, first/1, rest/1, group/2, filter/2, filter_map/2, map/2, map2/3, map_fold/3, index_map/2, try_map/2, drop/2, take/2, new/0, wrap/1, 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, unique/1, sort/2, repeat/2, split/2, split_while/2, key_find/2, key_filter/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, max/2, sample/2]).
-export_type([continue_or_stop/1, sorting/0]).
-if(?OTP_RELEASE >= 27).
-define(MODULEDOC(Str), -moduledoc(Str)).
-define(DOC(Str), -doc(Str)).
-else.
-define(MODULEDOC(Str), -compile([])).
-define(DOC(Str), -compile([])).
-endif.
?MODULEDOC(
" Lists are an ordered sequence of elements and are one of the most common\n"
" data types in Gleam.\n"
"\n"
" New elements can be added and removed from the front of a list in\n"
" constant time, while adding and removing from the end requires traversing\n"
" and copying the whole list, so keep this in mind when designing your\n"
" programs.\n"
"\n"
" There is a dedicated syntax for prefixing to a list:\n"
"\n"
" ```gleam\n"
" let new_list = [1, 2, ..existing_list]\n"
" ```\n"
"\n"
" And a matching syntax for getting the first elements of a list:\n"
"\n"
" ```gleam\n"
" case list {\n"
" [first_element, ..rest] -> first_element\n"
" _ -> \"this pattern matches when the list is empty\"\n"
" }\n"
" ```\n"
"\n"
).
-type continue_or_stop(AAL) :: {continue, AAL} | {stop, AAL}.
-type sorting() :: ascending | descending.
-file("src/gleeps/stdlib/list.gleam", 57).
-spec length_loop(list(any()), integer()) -> integer().
length_loop(List, Count) ->
case List of
[_ | List@1] ->
length_loop(List@1, Count + 1);
[] ->
Count
end.
-file("src/gleeps/stdlib/list.gleam", 53).
?DOC(
" Counts the number of elements in a given list.\n"
"\n"
" This function has to traverse the list to determine the number of elements,\n"
" so it runs in linear time.\n"
"\n"
" This function is natively implemented by the virtual machine and is highly\n"
" optimised.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert length([]) == 0\n"
" ```\n"
"\n"
" ```gleam\n"
" assert length([1]) == 1\n"
" ```\n"
"\n"
" ```gleam\n"
" assert length([1, 2]) == 2\n"
" ```\n"
).
-spec length(list(any())) -> integer().
length(List) ->
erlang:length(List).
-file("src/gleeps/stdlib/list.gleam", 87).
-spec count_loop(list(AAS), fun((AAS) -> boolean()), integer()) -> integer().
count_loop(List, Predicate, Acc) ->
case List of
[] ->
Acc;
[First | Rest] ->
case Predicate(First) of
true ->
count_loop(Rest, Predicate, Acc + 1);
false ->
count_loop(Rest, Predicate, Acc)
end
end.
-file("src/gleeps/stdlib/list.gleam", 83).
?DOC(
" Counts the number of elements in a given list satisfying a given predicate.\n"
"\n"
" This function has to traverse the list to determine the number of elements,\n"
" so it runs in linear time.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert count([], fn(a) { a > 0 }) == 0\n"
" ```\n"
"\n"
" ```gleam\n"
" assert count([1], fn(a) { a > 0 }) == 1\n"
" ```\n"
"\n"
" ```gleam\n"
" assert count([1, 2, 3], int.is_odd) == 2\n"
" ```\n"
).
-spec count(list(AAQ), fun((AAQ) -> boolean())) -> integer().
count(List, Predicate) ->
count_loop(List, Predicate, 0).
-file("src/gleeps/stdlib/list.gleam", 122).
?DOC(
" Creates a new list from a given list containing the same elements but in the\n"
" opposite order.\n"
"\n"
" This function has to traverse the list to create the new reversed list, so\n"
" it runs in linear time.\n"
"\n"
" This function is natively implemented by the virtual machine and is highly\n"
" optimised.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert reverse([]) == []\n"
" ```\n"
"\n"
" ```gleam\n"
" assert reverse([1]) == [1]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert reverse([1, 2]) == [2, 1]\n"
" ```\n"
).
-spec reverse(list(AAU)) -> list(AAU).
reverse(List) ->
lists:reverse(List).
-file("src/gleeps/stdlib/list.gleam", 156).
?DOC(
" Determines whether or not the list is empty.\n"
"\n"
" This function runs in constant time.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert is_empty([])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert !is_empty([1])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert !is_empty([1, 1])\n"
" ```\n"
).
-spec is_empty(list(any())) -> boolean().
is_empty(List) ->
List =:= [].
-file("src/gleeps/stdlib/list.gleam", 187).
?DOC(
" Determines whether or not a given element exists within a given list.\n"
"\n"
" This function traverses the list to find the element, so it runs in linear\n"
" time.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert !contains([], any: 0)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert [0] |> contains(any: 0)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert !contains([1], any: 0)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert !contains([1, 1], any: 0)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert [1, 0] |> contains(any: 0)\n"
" ```\n"
).
-spec contains(list(ABD), ABD) -> boolean().
contains(List, Elem) ->
case List of
[] ->
false;
[First | _] when First =:= Elem ->
true;
[_ | Rest] ->
contains(Rest, Elem)
end.
-file("src/gleeps/stdlib/list.gleam", 211).
?DOC(
" Gets the first element from the start of the list, if there is one.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert first([]) == Error(Nil)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert first([0]) == Ok(0)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert first([1, 2]) == Ok(1)\n"
" ```\n"
).
-spec first(list(ABF)) -> {ok, ABF} | {error, nil}.
first(List) ->
case List of
[] ->
{error, nil};
[First | _] ->
{ok, First}
end.
-file("src/gleeps/stdlib/list.gleam", 237).
?DOC(
" Returns the list minus the first element. If the list is empty, `Error(Nil)` is\n"
" returned.\n"
"\n"
" This function runs in constant time and does not make a copy of the list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert rest([]) == Error(Nil)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert rest([0]) == Ok([])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert rest([1, 2]) == Ok([2])\n"
" ```\n"
).
-spec rest(list(ABJ)) -> {ok, list(ABJ)} | {error, nil}.
rest(List) ->
case List of
[] ->
{error, nil};
[_ | Rest] ->
{ok, Rest}
end.
-file("src/gleeps/stdlib/list.gleam", 276).
?DOC(
" Groups the elements from the given list by the given key function.\n"
"\n"
" Does not preserve the initial value order.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" import gleam/dict\n"
"\n"
" assert\n"
" [Ok(3), Error(\"Wrong\"), Ok(200), Ok(73)]\n"
" |> group(by: fn(i) {\n"
" case i {\n"
" Ok(_) -> \"Successful\"\n"
" Error(_) -> \"Failed\"\n"
" }\n"
" })\n"
" |> dict.to_list\n"
" == [\n"
" #(\"Failed\", [Error(\"Wrong\")]),\n"
" #(\"Successful\", [Ok(73), Ok(200), Ok(3)])\n"
" ]\n"
" ```\n"
"\n"
" ```gleam\n"
" import gleam/dict\n"
"\n"
" assert group([1,2,3,4,5], by: fn(i) { i - i / 3 * 3 })\n"
" |> dict.to_list\n"
" == [#(0, [3]), #(1, [4, 1]), #(2, [5, 2])]\n"
" ```\n"
).
-spec group(list(ABO), fun((ABO) -> ABQ)) -> gleeps@stdlib@dict:dict(ABQ, list(ABO)).
group(List, Key) ->
gleeps@stdlib@dict:group(Key, List).
-file("src/gleeps/stdlib/list.gleam", 297).
-spec filter_loop(list(ABX), fun((ABX) -> boolean()), list(ABX)) -> list(ABX).
filter_loop(List, Fun, Acc) ->
case List of
[] ->
lists:reverse(Acc);
[First | Rest] ->
New_acc = case Fun(First) of
true ->
[First | Acc];
false ->
Acc
end,
filter_loop(Rest, Fun, New_acc)
end.
-file("src/gleeps/stdlib/list.gleam", 293).
?DOC(
" Returns a new list containing only the elements from the first list for\n"
" which the given functions returns `True`.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert filter([2, 4, 6, 1], fn(x) { x > 2 }) == [4, 6]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert filter([2, 4, 6, 1], fn(x) { x > 6 }) == []\n"
" ```\n"
).
-spec filter(list(ABU), fun((ABU) -> boolean())) -> list(ABU).
filter(List, Predicate) ->
filter_loop(List, Predicate, []).
-file("src/gleeps/stdlib/list.gleam", 327).
-spec filter_map_loop(
list(ACI),
fun((ACI) -> {ok, ACK} | {error, any()}),
list(ACK)
) -> list(ACK).
filter_map_loop(List, Fun, Acc) ->
case List of
[] ->
lists:reverse(Acc);
[First | Rest] ->
New_acc = case Fun(First) of
{ok, First@1} ->
[First@1 | Acc];
{error, _} ->
Acc
end,
filter_map_loop(Rest, Fun, New_acc)
end.
-file("src/gleeps/stdlib/list.gleam", 323).
?DOC(
" Returns a new list containing only the elements from the first list for\n"
" which the given functions returns `Ok(_)`.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert filter_map([2, 4, 6, 1], Error) == []\n"
" ```\n"
"\n"
" ```gleam\n"
" assert filter_map([2, 4, 6, 1], fn(x) { Ok(x + 1) }) == [3, 5, 7, 2]\n"
" ```\n"
).
-spec filter_map(list(ACB), fun((ACB) -> {ok, ACD} | {error, any()})) -> list(ACD).
filter_map(List, Fun) ->
filter_map_loop(List, Fun, []).
-file("src/gleeps/stdlib/list.gleam", 356).
-spec map_loop(list(ACU), fun((ACU) -> ACW), list(ACW)) -> list(ACW).
map_loop(List, Fun, Acc) ->
case List of
[] ->
lists:reverse(Acc);
[First | Rest] ->
map_loop(Rest, Fun, [Fun(First) | Acc])
end.
-file("src/gleeps/stdlib/list.gleam", 352).
?DOC(
" Returns a new list containing the results of applying the supplied function to each element.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert map([2, 4, 6], fn(x) { x * 2 }) == [4, 8, 12]\n"
" ```\n"
).
-spec map(list(ACQ), fun((ACQ) -> ACS)) -> list(ACS).
map(List, Fun) ->
map_loop(List, Fun, []).
-file("src/gleeps/stdlib/list.gleam", 386).
-spec map2_loop(list(ADF), list(ADH), fun((ADF, ADH) -> ADJ), list(ADJ)) -> list(ADJ).
map2_loop(List1, List2, Fun, Acc) ->
case {List1, List2} of
{[], _} ->
lists:reverse(Acc);
{_, []} ->
lists:reverse(Acc);
{[A | As_], [B | Bs]} ->
map2_loop(As_, Bs, Fun, [Fun(A, B) | Acc])
end.
-file("src/gleeps/stdlib/list.gleam", 378).
?DOC(
" Combines two lists into a single list using the given function.\n"
"\n"
" If a list is longer than the other, the extra elements are dropped.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert map2([1, 2, 3], [4, 5, 6], fn(x, y) { x + y }) == [5, 7, 9]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert map2([1, 2], [\"a\", \"b\", \"c\"], fn(i, x) { #(i, x) })\n"
" == [#(1, \"a\"), #(2, \"b\")]\n"
" ```\n"
).
-spec map2(list(ACZ), list(ADB), fun((ACZ, ADB) -> ADD)) -> list(ADD).
map2(List1, List2, Fun) ->
map2_loop(List1, List2, Fun, []).
-file("src/gleeps/stdlib/list.gleam", 420).
-spec map_fold_loop(list(ADR), fun((ADT, ADR) -> {ADT, ADU}), ADT, list(ADU)) -> {ADT,
list(ADU)}.
map_fold_loop(List, Fun, Acc, List_acc) ->
case List of
[] ->
{Acc, lists:reverse(List_acc)};
[First | Rest] ->
{Acc@1, First@1} = Fun(Acc, First),
map_fold_loop(Rest, Fun, Acc@1, [First@1 | List_acc])
end.
-file("src/gleeps/stdlib/list.gleam", 412).
?DOC(
" Similar to `map` but also lets you pass around an accumulated value.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert\n"
" map_fold(\n"
" over: [1, 2, 3],\n"
" from: 100,\n"
" with: fn(memo, i) { #(memo + i, i * 2) }\n"
" )\n"
" == #(106, [2, 4, 6])\n"
" ```\n"
).
-spec map_fold(list(ADM), ADO, fun((ADO, ADM) -> {ADO, ADP})) -> {ADO,
list(ADP)}.
map_fold(List, Initial, Fun) ->
map_fold_loop(List, Fun, Initial, []).
-file("src/gleeps/stdlib/list.gleam", 451).
-spec index_map_loop(
list(AEB),
fun((AEB, integer()) -> AED),
integer(),
list(AED)
) -> list(AED).
index_map_loop(List, Fun, Index, Acc) ->
case List of
[] ->
lists:reverse(Acc);
[First | Rest] ->
Acc@1 = [Fun(First, Index) | Acc],
index_map_loop(Rest, Fun, Index + 1, Acc@1)
end.
-file("src/gleeps/stdlib/list.gleam", 447).
?DOC(
" Similar to `map`, but the supplied function will also be passed the index\n"
" of the element being mapped as an additional argument.\n"
"\n"
" The index starts at 0, so the first element is 0, the second is 1, and so\n"
" on.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert index_map([\"a\", \"b\"], fn(x, i) { #(i, x) }) == [#(0, \"a\"), #(1, \"b\")]\n"
" ```\n"
).
-spec index_map(list(ADX), fun((ADX, integer()) -> ADZ)) -> list(ADZ).
index_map(List, Fun) ->
index_map_loop(List, Fun, 0, []).
-file("src/gleeps/stdlib/list.gleam", 501).
-spec try_map_loop(list(AEP), fun((AEP) -> {ok, AER} | {error, AES}), list(AER)) -> {ok,
list(AER)} |
{error, AES}.
try_map_loop(List, Fun, Acc) ->
case List of
[] ->
{ok, lists:reverse(Acc)};
[First | Rest] ->
case Fun(First) of
{ok, First@1} ->
try_map_loop(Rest, Fun, [First@1 | Acc]);
{error, Error} ->
{error, Error}
end
end.
-file("src/gleeps/stdlib/list.gleam", 494).
?DOC(
" Takes a function that returns a `Result` and applies it to each element in a\n"
" given list in turn.\n"
"\n"
" If the function returns `Ok(new_value)` for all elements in the list then a\n"
" list of the new values is returned.\n"
"\n"
" If the function returns `Error(reason)` for any of the elements then it is\n"
" returned immediately. None of the elements in the list are processed after\n"
" one returns an `Error`.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert try_map([1, 2, 3], fn(x) { Ok(x + 2) }) == Ok([3, 4, 5])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert try_map([1, 2, 3], fn(_) { Error(0) }) == Error(0)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert try_map([[1], [2, 3]], first) == Ok([1, 2])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert try_map([[1], [], [2]], first) == Error(Nil)\n"
" ```\n"
).
-spec try_map(list(AEG), fun((AEG) -> {ok, AEI} | {error, AEJ})) -> {ok,
list(AEI)} |
{error, AEJ}.
try_map(List, Fun) ->
try_map_loop(List, Fun, []).
-file("src/gleeps/stdlib/list.gleam", 534).
?DOC(
" Returns a list that is the given list with up to the given number of\n"
" elements removed from the front of the list.\n"
"\n"
" If the list has less than the number of elements an empty list is\n"
" returned.\n"
"\n"
" This function runs in linear time but does not copy the list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert drop([1, 2, 3, 4], 2) == [3, 4]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert drop([1, 2, 3, 4], 9) == []\n"
" ```\n"
).
-spec drop(list(AEZ), integer()) -> list(AEZ).
drop(List, N) ->
case N =< 0 of
true ->
List;
false ->
case List of
[] ->
[];
[_ | Rest] ->
drop(Rest, N - 1)
end
end.
-file("src/gleeps/stdlib/list.gleam", 567).
-spec take_loop(list(AFF), integer(), list(AFF)) -> list(AFF).
take_loop(List, N, Acc) ->
case N =< 0 of
true ->
lists:reverse(Acc);
false ->
case List of
[] ->
lists:reverse(Acc);
[First | Rest] ->
take_loop(Rest, N - 1, [First | Acc])
end
end.
-file("src/gleeps/stdlib/list.gleam", 563).
?DOC(
" Returns a list containing the first given number of elements from the given\n"
" list.\n"
"\n"
" If the list has less than the number of elements then the full list is\n"
" returned.\n"
"\n"
" This function runs in linear time.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert take([1, 2, 3, 4], 2) == [1, 2]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert take([1, 2, 3, 4], 9) == [1, 2, 3, 4]\n"
" ```\n"
).
-spec take(list(AFC), integer()) -> list(AFC).
take(List, N) ->
take_loop(List, N, []).
-file("src/gleeps/stdlib/list.gleam", 586).
?DOC(
" Returns a new empty list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert new() == []\n"
" ```\n"
).
-spec new() -> list(any()).
new() ->
[].
-file("src/gleeps/stdlib/list.gleam", 607).
?DOC(
" Returns the given item wrapped in a list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert wrap(1) == [1]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert wrap([\"a\", \"b\", \"c\"]) == [[\"a\", \"b\", \"c\"]]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert wrap([[]]) == [[[]]]\n"
" ```\n"
).
-spec wrap(AFL) -> list(AFL).
wrap(Item) ->
[Item].
-file("src/gleeps/stdlib/list.gleam", 627).
-spec append_loop(list(AFR), list(AFR)) -> list(AFR).
append_loop(First, Second) ->
case First of
[] ->
Second;
[First@1 | Rest] ->
append_loop(Rest, [First@1 | Second])
end.
-file("src/gleeps/stdlib/list.gleam", 623).
?DOC(
" Joins one list onto the end of another.\n"
"\n"
" This function runs in linear time, and it traverses and copies the first\n"
" list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert append([1, 2], [3]) == [1, 2, 3]\n"
" ```\n"
).
-spec append(list(AFN), list(AFN)) -> list(AFN).
append(First, Second) ->
lists:append(First, Second).
-file("src/gleeps/stdlib/list.gleam", 647).
?DOC(
" Prefixes an item to a list. This can also be done using the dedicated\n"
" syntax instead.\n"
"\n"
" ```gleam\n"
" let existing_list = [2, 3, 4]\n"
" assert [1, ..existing_list] == [1, 2, 3, 4]\n"
" ```\n"
"\n"
" ```gleam\n"
" let existing_list = [2, 3, 4]\n"
" assert prepend(to: existing_list, this: 1) == [1, 2, 3, 4]\n"
" ```\n"
).
-spec prepend(list(AFV), AFV) -> list(AFV).
prepend(List, Item) ->
[Item | List].
-file("src/gleeps/stdlib/list.gleam", 667).
-spec flatten_loop(list(list(AGC)), list(AGC)) -> list(AGC).
flatten_loop(Lists, Acc) ->
case Lists of
[] ->
lists:reverse(Acc);
[List | Further_lists] ->
flatten_loop(Further_lists, lists:reverse(List, Acc))
end.
-file("src/gleeps/stdlib/list.gleam", 663).
?DOC(
" Joins a list of lists into a single list.\n"
"\n"
" This function traverses all elements twice on the JavaScript target.\n"
" This function traverses all elements once on the Erlang target.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert flatten([[1], [2, 3], []]) == [1, 2, 3]\n"
" ```\n"
).
-spec flatten(list(list(AFY))) -> list(AFY).
flatten(Lists) ->
lists:append(Lists).
-file("src/gleeps/stdlib/list.gleam", 683).
?DOC(
" Maps the list with the given function into a list of lists, and then flattens it.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert flat_map([2, 4, 6], fn(x) { [x, x + 1] }) == [2, 3, 4, 5, 6, 7]\n"
" ```\n"
).
-spec flat_map(list(AGH), fun((AGH) -> list(AGJ))) -> list(AGJ).
flat_map(List, Fun) ->
lists:append(map(List, Fun)).
-file("src/gleeps/stdlib/list.gleam", 695).
?DOC(
" Reduces a list of elements into a single value by calling a given function\n"
" on each element, going from left to right.\n"
"\n"
" `fold([1, 2, 3], 0, add)` is the equivalent of\n"
" `add(add(add(0, 1), 2), 3)`.\n"
"\n"
" This function runs in linear time.\n"
).
-spec fold(list(AGM), AGO, fun((AGO, AGM) -> AGO)) -> AGO.
fold(List, Initial, Fun) ->
case List of
[] ->
Initial;
[First | Rest] ->
fold(Rest, Fun(Initial, First), Fun)
end.
-file("src/gleeps/stdlib/list.gleam", 717).
?DOC(
" Reduces a list of elements into a single value by calling a given function\n"
" on each element, going from right to left.\n"
"\n"
" `fold_right([1, 2, 3], 0, add)` is the equivalent of\n"
" `add(add(add(0, 3), 2), 1)`.\n"
"\n"
" This function runs in linear time.\n"
"\n"
" Unlike `fold` this function is not tail recursive. Where possible use\n"
" `fold` instead as it will use less memory.\n"
).
-spec fold_right(list(AGP), AGR, fun((AGR, AGP) -> AGR)) -> AGR.
fold_right(List, Initial, Fun) ->
case List of
[] ->
Initial;
[First | Rest] ->
Fun(fold_right(Rest, Initial, Fun), First)
end.
-file("src/gleeps/stdlib/list.gleam", 754).
-spec index_fold_loop(
list(AGV),
AGX,
fun((AGX, AGV, integer()) -> AGX),
integer()
) -> AGX.
index_fold_loop(Over, Acc, With, Index) ->
case Over of
[] ->
Acc;
[First | Rest] ->
index_fold_loop(Rest, With(Acc, First, Index), With, Index + 1)
end.
-file("src/gleeps/stdlib/list.gleam", 746).
?DOC(
" Like `fold` but the folding function also receives the index of the current element.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert [\"a\", \"b\", \"c\"]\n"
" |> index_fold(\"\", fn(acc, item, index) {\n"
" acc <> int.to_string(index) <> \":\" <> item <> \" \"\n"
" })\n"
" == \"0:a 1:b 2:c\"\n"
" ```\n"
"\n"
" ```gleam\n"
" assert [10, 20, 30]\n"
" |> index_fold(0, fn(acc, item, index) { acc + item * index })\n"
" == 80\n"
" ```\n"
).
-spec index_fold(list(AGS), AGU, fun((AGU, AGS, integer()) -> AGU)) -> AGU.
index_fold(List, Initial, Fun) ->
index_fold_loop(List, Initial, Fun, 0).
-file("src/gleeps/stdlib/list.gleam", 786).
?DOC(
" A variant of fold that might fail.\n"
"\n"
" The folding function should return `Result(accumulator, error)`.\n"
" If the returned value is `Ok(accumulator)` try_fold will try the next value in the list.\n"
" If the returned value is `Error(error)` try_fold will stop and return that error.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert [1, 2, 3, 4]\n"
" |> try_fold(0, fn(acc, i) {\n"
" case i < 3 {\n"
" True -> Ok(acc + i)\n"
" False -> Error(Nil)\n"
" }\n"
" })\n"
" == Error(Nil)\n"
" ```\n"
).
-spec try_fold(list(AGY), AHA, fun((AHA, AGY) -> {ok, AHA} | {error, AHB})) -> {ok,
AHA} |
{error, AHB}.
try_fold(List, Initial, Fun) ->
case List of
[] ->
{ok, Initial};
[First | Rest] ->
case Fun(Initial, First) of
{ok, Result} ->
try_fold(Rest, Result, Fun);
{error, _} = Error ->
Error
end
end.
-file("src/gleeps/stdlib/list.gleam", 825).
?DOC(
" A variant of fold that allows to stop folding earlier.\n"
"\n"
" The folding function should return `ContinueOrStop(accumulator)`.\n"
" If the returned value is `Continue(accumulator)` fold_until will try the next value in the list.\n"
" If the returned value is `Stop(accumulator)` fold_until will stop and return that accumulator.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert [1, 2, 3, 4]\n"
" |> fold_until(0, fn(acc, i) {\n"
" case i < 3 {\n"
" True -> Continue(acc + i)\n"
" False -> Stop(acc)\n"
" }\n"
" })\n"
" == 3\n"
" ```\n"
).
-spec fold_until(list(AHG), AHI, fun((AHI, AHG) -> continue_or_stop(AHI))) -> AHI.
fold_until(List, Initial, Fun) ->
case List of
[] ->
Initial;
[First | Rest] ->
case Fun(Initial, First) of
{continue, Next_accumulator} ->
fold_until(Rest, Next_accumulator, Fun);
{stop, B} ->
B
end
end.
-file("src/gleeps/stdlib/list.gleam", 859).
?DOC(
" Finds the first element in a given list for which the given function returns\n"
" `True`.\n"
"\n"
" Returns `Error(Nil)` if no such element is found.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert find([1, 2, 3], fn(x) { x > 2 }) == Ok(3)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert find([1, 2, 3], fn(x) { x > 4 }) == Error(Nil)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert find([], fn(_) { True }) == Error(Nil)\n"
" ```\n"
).
-spec find(list(AHK), fun((AHK) -> boolean())) -> {ok, AHK} | {error, nil}.
find(List, Is_desired) ->
case List of
[] ->
{error, nil};
[First | Rest] ->
case Is_desired(First) of
true ->
{ok, First};
false ->
find(Rest, Is_desired)
end
end.
-file("src/gleeps/stdlib/list.gleam", 892).
?DOC(
" Finds the first element in a given list for which the given function returns\n"
" `Ok(new_value)`, then returns the wrapped `new_value`.\n"
"\n"
" Returns `Error(Nil)` if no such element is found.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert find_map([[], [2], [3]], first) == Ok(2)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert find_map([[], []], first) == Error(Nil)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert find_map([], first) == Error(Nil)\n"
" ```\n"
).
-spec find_map(list(AHO), fun((AHO) -> {ok, AHQ} | {error, any()})) -> {ok, AHQ} |
{error, nil}.
find_map(List, Fun) ->
case List of
[] ->
{error, nil};
[First | Rest] ->
case Fun(First) of
{ok, First@1} ->
{ok, First@1};
{error, _} ->
find_map(Rest, Fun)
end
end.
-file("src/gleeps/stdlib/list.gleam", 924).
?DOC(
" Returns `True` if the given function returns `True` for all the elements in\n"
" the given list. If the function returns `False` for any of the elements it\n"
" immediately returns `False` without checking the rest of the list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert all([], fn(x) { x > 3 })\n"
" ```\n"
"\n"
" ```gleam\n"
" assert all([4, 5], fn(x) { x > 3 })\n"
" ```\n"
"\n"
" ```gleam\n"
" assert !all([4, 3], fn(x) { x > 3 })\n"
" ```\n"
).
-spec all(list(AHW), fun((AHW) -> boolean())) -> boolean().
all(List, Predicate) ->
case List of
[] ->
true;
[First | Rest] ->
case Predicate(First) of
true ->
all(Rest, Predicate);
false ->
false
end
end.
-file("src/gleeps/stdlib/list.gleam", 957).
?DOC(
" Returns `True` if the given function returns `True` for any the elements in\n"
" the given list. If the function returns `True` for any of the elements it\n"
" immediately returns `True` without checking the rest of the list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert !any([], fn(x) { x > 3 })\n"
" ```\n"
"\n"
" ```gleam\n"
" assert any([4, 5], fn(x) { x > 3 })\n"
" ```\n"
"\n"
" ```gleam\n"
" assert any([4, 3], fn(x) { x > 4 })\n"
" ```\n"
"\n"
" ```gleam\n"
" assert any([3, 4], fn(x) { x > 3 })\n"
" ```\n"
).
-spec any(list(AHY), fun((AHY) -> boolean())) -> boolean().
any(List, Predicate) ->
case List of
[] ->
false;
[First | Rest] ->
case Predicate(First) of
true ->
true;
false ->
any(Rest, Predicate)
end
end.
-file("src/gleeps/stdlib/list.gleam", 995).
-spec zip_loop(list(AIF), list(AIH), list({AIF, AIH})) -> list({AIF, AIH}).
zip_loop(One, Other, Acc) ->
case {One, Other} of
{[First_one | Rest_one], [First_other | Rest_other]} ->
zip_loop(Rest_one, Rest_other, [{First_one, First_other} | Acc]);
{_, _} ->
lists:reverse(Acc)
end.
-file("src/gleeps/stdlib/list.gleam", 991).
?DOC(
" Takes two lists and returns a single list of 2-element tuples.\n"
"\n"
" If one of the lists is longer than the other, the remaining elements from\n"
" the longer list are not used.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert zip([], []) == []\n"
" ```\n"
"\n"
" ```gleam\n"
" assert zip([1, 2], [3]) == [#(1, 3)]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert zip([1], [3, 4]) == [#(1, 3)]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert zip([1, 2], [3, 4]) == [#(1, 3), #(2, 4)]\n"
" ```\n"
).
-spec zip(list(AIA), list(AIC)) -> list({AIA, AIC}).
zip(List, Other) ->
zip_loop(List, Other, []).
-file("src/gleeps/stdlib/list.gleam", 1032).
-spec strict_zip_loop(list(AIS), list(AIU), list({AIS, AIU})) -> {ok,
list({AIS, AIU})} |
{error, nil}.
strict_zip_loop(One, Other, Acc) ->
case {One, Other} of
{[], []} ->
{ok, lists:reverse(Acc)};
{[], _} ->
{error, nil};
{_, []} ->
{error, nil};
{[First_one | Rest_one], [First_other | Rest_other]} ->
strict_zip_loop(
Rest_one,
Rest_other,
[{First_one, First_other} | Acc]
)
end.
-file("src/gleeps/stdlib/list.gleam", 1025).
?DOC(
" Takes two lists and returns a single list of 2-element tuples.\n"
"\n"
" If one of the lists is longer than the other, an `Error` is returned.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert strict_zip([], []) == Ok([])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert strict_zip([1, 2], [3]) == Error(Nil)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert strict_zip([1], [3, 4]) == Error(Nil)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert strict_zip([1, 2], [3, 4]) == Ok([#(1, 3), #(2, 4)])\n"
" ```\n"
).
-spec strict_zip(list(AIL), list(AIN)) -> {ok, list({AIL, AIN})} | {error, nil}.
strict_zip(List, Other) ->
strict_zip_loop(List, Other, []).
-file("src/gleeps/stdlib/list.gleam", 1061).
-spec unzip_loop(list({AJF, AJG}), list(AJF), list(AJG)) -> {list(AJF),
list(AJG)}.
unzip_loop(Input, One, Other) ->
case Input of
[] ->
{lists:reverse(One), lists:reverse(Other)};
[{First_one, First_other} | Rest] ->
unzip_loop(Rest, [First_one | One], [First_other | Other])
end.
-file("src/gleeps/stdlib/list.gleam", 1057).
?DOC(
" Takes a single list of 2-element tuples and returns two lists.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert unzip([#(1, 2), #(3, 4)]) == #([1, 3], [2, 4])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert unzip([]) == #([], [])\n"
" ```\n"
).
-spec unzip(list({AJA, AJB})) -> {list(AJA), list(AJB)}.
unzip(Input) ->
unzip_loop(Input, [], []).
-file("src/gleeps/stdlib/list.gleam", 1094).
-spec intersperse_loop(list(AJP), AJP, list(AJP)) -> list(AJP).
intersperse_loop(List, Separator, Acc) ->
case List of
[] ->
lists:reverse(Acc);
[First | Rest] ->
intersperse_loop(Rest, Separator, [First, Separator | Acc])
end.
-file("src/gleeps/stdlib/list.gleam", 1087).
?DOC(
" Inserts a given value between each existing element in a given list.\n"
"\n"
" This function runs in linear time and copies the list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert intersperse([1, 1, 1], 2) == [1, 2, 1, 2, 1]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert intersperse([], 2) == []\n"
" ```\n"
).
-spec intersperse(list(AJM), AJM) -> list(AJM).
intersperse(List, Elem) ->
case List of
[] ->
List;
[_] ->
List;
[First | Rest] ->
intersperse_loop(Rest, Elem, [First])
end.
-file("src/gleeps/stdlib/list.gleam", 1116).
-spec unique_loop(list(AJW), gleeps@stdlib@dict:dict(AJW, nil), list(AJW)) -> list(AJW).
unique_loop(List, Seen, Acc) ->
case List of
[] ->
lists:reverse(Acc);
[First | Rest] ->
case gleeps@stdlib@dict:has_key(Seen, First) of
true ->
unique_loop(Rest, Seen, Acc);
false ->
unique_loop(
Rest,
gleeps@stdlib@dict:insert(Seen, First, nil),
[First | Acc]
)
end
end.
-file("src/gleeps/stdlib/list.gleam", 1112).
?DOC(
" Removes any duplicate elements from a given list.\n"
"\n"
" This function returns in loglinear time.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert unique([1, 1, 1, 4, 7, 3, 3, 4]) == [1, 4, 7, 3]\n"
" ```\n"
).
-spec unique(list(AJT)) -> list(AJT).
unique(List) ->
unique_loop(List, maps:new(), []).
-file("src/gleeps/stdlib/list.gleam", 1376).
?DOC(
" This is exactly the same as merge_ascendings but mirrored: it merges two\n"
" lists sorted in descending order into a single list sorted in ascending\n"
" order according to the given comparator function.\n"
"\n"
" This reversing of the sort order is not avoidable if we want to implement\n"
" merge as a tail recursive function. We could reverse the accumulator before\n"
" returning it but that would end up being less efficient; so the merging\n"
" algorithm has to play around this.\n"
).
-spec merge_descendings(
list(ALH),
list(ALH),
fun((ALH, ALH) -> gleeps@stdlib@order:order()),
list(ALH)
) -> list(ALH).
merge_descendings(List1, List2, Compare, Acc) ->
case {List1, List2} of
{[], List} ->
lists:reverse(List, Acc);
{List, []} ->
lists:reverse(List, Acc);
{[First1 | Rest1], [First2 | Rest2]} ->
case Compare(First1, First2) of
lt ->
merge_descendings(List1, Rest2, Compare, [First2 | Acc]);
gt ->
merge_descendings(Rest1, List2, Compare, [First1 | Acc]);
eq ->
merge_descendings(Rest1, List2, Compare, [First1 | Acc])
end
end.
-file("src/gleeps/stdlib/list.gleam", 1324).
?DOC(" This is the same as merge_ascending_pairs but flipped for descending lists.\n").
-spec merge_descending_pairs(
list(list(AKW)),
fun((AKW, AKW) -> gleeps@stdlib@order:order()),
list(list(AKW))
) -> list(list(AKW)).
merge_descending_pairs(Sequences, Compare, Acc) ->
case Sequences of
[] ->
lists:reverse(Acc);
[Sequence] ->
lists:reverse([lists:reverse(Sequence) | Acc]);
[Descending1, Descending2 | Rest] ->
Ascending = merge_descendings(Descending1, Descending2, Compare, []),
merge_descending_pairs(Rest, Compare, [Ascending | Acc])
end.
-file("src/gleeps/stdlib/list.gleam", 1349).
?DOC(
" Merges two lists sorted in ascending order into a single list sorted in\n"
" descending order according to the given comparator function.\n"
"\n"
" This reversing of the sort order is not avoidable if we want to implement\n"
" merge as a tail recursive function. We could reverse the accumulator before\n"
" returning it but that would end up being less efficient; so the merging\n"
" algorithm has to play around this.\n"
).
-spec merge_ascendings(
list(ALC),
list(ALC),
fun((ALC, ALC) -> gleeps@stdlib@order:order()),
list(ALC)
) -> list(ALC).
merge_ascendings(List1, List2, Compare, Acc) ->
case {List1, List2} of
{[], List} ->
lists:reverse(List, Acc);
{List, []} ->
lists:reverse(List, Acc);
{[First1 | Rest1], [First2 | Rest2]} ->
case Compare(First1, First2) of
lt ->
merge_ascendings(Rest1, List2, Compare, [First1 | Acc]);
gt ->
merge_ascendings(List1, Rest2, Compare, [First2 | Acc]);
eq ->
merge_ascendings(List1, Rest2, Compare, [First2 | Acc])
end
end.
-file("src/gleeps/stdlib/list.gleam", 1302).
?DOC(
" Given a list of ascending lists, it merges adjacent pairs into a single\n"
" descending list, halving their number.\n"
" It returns a list of the remaining descending lists.\n"
).
-spec merge_ascending_pairs(
list(list(AKQ)),
fun((AKQ, AKQ) -> gleeps@stdlib@order:order()),
list(list(AKQ))
) -> list(list(AKQ)).
merge_ascending_pairs(Sequences, Compare, Acc) ->
case Sequences of
[] ->
lists:reverse(Acc);
[Sequence] ->
lists:reverse([lists:reverse(Sequence) | Acc]);
[Ascending1, Ascending2 | Rest] ->
Descending = merge_ascendings(Ascending1, Ascending2, Compare, []),
merge_ascending_pairs(Rest, Compare, [Descending | Acc])
end.
-file("src/gleeps/stdlib/list.gleam", 1268).
?DOC(
" Given some some sorted sequences (assumed to be sorted in `direction`) it\n"
" merges them all together until we're left with just a list sorted in\n"
" ascending order.\n"
).
-spec merge_all(
list(list(AKM)),
sorting(),
fun((AKM, AKM) -> gleeps@stdlib@order:order())
) -> list(AKM).
merge_all(Sequences, Direction, Compare) ->
case {Sequences, Direction} of
{[], _} ->
[];
{[Sequence], ascending} ->
Sequence;
{[Sequence@1], descending} ->
lists:reverse(Sequence@1);
{_, ascending} ->
Sequences@1 = merge_ascending_pairs(Sequences, Compare, []),
merge_all(Sequences@1, descending, Compare);
{_, descending} ->
Sequences@2 = merge_descending_pairs(Sequences, Compare, []),
merge_all(Sequences@2, ascending, Compare)
end.
-file("src/gleeps/stdlib/list.gleam", 1201).
?DOC(
" Given a list it returns slices of it that are locally sorted in ascending\n"
" order.\n"
"\n"
" Imagine you have this list:\n"
"\n"
" ```\n"
" [1, 2, 3, 2, 1, 0]\n"
" ^^^^^^^ ^^^^^^^ This is a slice in descending order\n"
" |\n"
" | This is a slice that is sorted in ascending order\n"
" ```\n"
"\n"
" So the produced result will contain these two slices, each one sorted in\n"
" ascending order: `[[1, 2, 3], [0, 1, 2]]`.\n"
"\n"
" - `growing` is an accumulator with the current slice being grown\n"
" - `direction` is the growing direction of the slice being grown, it could\n"
" either be ascending or strictly descending\n"
" - `prev` is the previous element that needs to be added to the growing slice\n"
" it is carried around to check whether we have to keep growing the current\n"
" slice or not\n"
" - `acc` is the accumulator containing the slices sorted in ascending order\n"
).
-spec sequences(
list(AKF),
fun((AKF, AKF) -> gleeps@stdlib@order:order()),
list(AKF),
sorting(),
AKF,
list(list(AKF))
) -> list(list(AKF)).
sequences(List, Compare, Growing, Direction, Prev, Acc) ->
Growing@1 = [Prev | Growing],
case List of
[] ->
case Direction of
ascending ->
[lists:reverse(Growing@1) | Acc];
descending ->
[Growing@1 | Acc]
end;
[New | Rest] ->
case {Compare(Prev, New), Direction} of
{gt, descending} ->
sequences(Rest, Compare, Growing@1, Direction, New, Acc);
{lt, ascending} ->
sequences(Rest, Compare, Growing@1, Direction, New, Acc);
{eq, ascending} ->
sequences(Rest, Compare, Growing@1, Direction, New, Acc);
{gt, ascending} ->
Acc@1 = case Direction of
ascending ->
[lists:reverse(Growing@1) | Acc];
descending ->
[Growing@1 | Acc]
end,
case Rest of
[] ->
[[New] | Acc@1];
[Next | Rest@1] ->
Direction@1 = case Compare(New, Next) of
lt ->
ascending;
eq ->
ascending;
gt ->
descending
end,
sequences(
Rest@1,
Compare,
[New],
Direction@1,
Next,
Acc@1
)
end;
{lt, descending} ->
Acc@1 = case Direction of
ascending ->
[lists:reverse(Growing@1) | Acc];
descending ->
[Growing@1 | Acc]
end,
case Rest of
[] ->
[[New] | Acc@1];
[Next | Rest@1] ->
Direction@1 = case Compare(New, Next) of
lt ->
ascending;
eq ->
ascending;
gt ->
descending
end,
sequences(
Rest@1,
Compare,
[New],
Direction@1,
Next,
Acc@1
)
end;
{eq, descending} ->
Acc@1 = case Direction of
ascending ->
[lists:reverse(Growing@1) | Acc];
descending ->
[Growing@1 | Acc]
end,
case Rest of
[] ->
[[New] | Acc@1];
[Next | Rest@1] ->
Direction@1 = case Compare(New, Next) of
lt ->
ascending;
eq ->
ascending;
gt ->
descending
end,
sequences(
Rest@1,
Compare,
[New],
Direction@1,
Next,
Acc@1
)
end
end
end.
-file("src/gleeps/stdlib/list.gleam", 1139).
?DOC(
" Sorts from smallest to largest based upon the ordering specified by a given\n"
" function.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" import gleam/int\n"
"\n"
" assert sort([4, 3, 6, 5, 4, 1, 2], by: int.compare) == [1, 2, 3, 4, 4, 5, 6]\n"
" ```\n"
).
-spec sort(list(AKC), fun((AKC, AKC) -> gleeps@stdlib@order:order())) -> list(AKC).
sort(List, Compare) ->
case List of
[] ->
[];
[X] ->
[X];
[X@1, Y | Rest] ->
Direction = case Compare(X@1, Y) of
lt ->
ascending;
eq ->
ascending;
gt ->
descending
end,
Sequences = sequences(Rest, Compare, [X@1], Direction, Y, []),
merge_all(Sequences, ascending, Compare)
end.
-file("src/gleeps/stdlib/list.gleam", 1409).
-spec repeat_loop(ALO, integer(), list(ALO)) -> list(ALO).
repeat_loop(Item, Times, Acc) ->
case Times =< 0 of
true ->
Acc;
false ->
repeat_loop(Item, Times - 1, [Item | Acc])
end.
-file("src/gleeps/stdlib/list.gleam", 1405).
?DOC(
" Builds a list of a given value a given number of times.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert repeat(\"a\", times: 0) == []\n"
" ```\n"
"\n"
" ```gleam\n"
" assert repeat(\"a\", times: 5) == [\"a\", \"a\", \"a\", \"a\", \"a\"]\n"
" ```\n"
).
-spec repeat(ALM, integer()) -> list(ALM).
repeat(A, Times) ->
repeat_loop(A, Times, []).
-file("src/gleeps/stdlib/list.gleam", 1439).
-spec split_loop(list(ALV), integer(), list(ALV)) -> {list(ALV), list(ALV)}.
split_loop(List, N, Taken) ->
case N =< 0 of
true ->
{lists:reverse(Taken), List};
false ->
case List of
[] ->
{lists:reverse(Taken), []};
[First | Rest] ->
split_loop(Rest, N - 1, [First | Taken])
end
end.
-file("src/gleeps/stdlib/list.gleam", 1435).
?DOC(
" Splits a list in two before the given index.\n"
"\n"
" If the list is not long enough to have the given index the before list will\n"
" be the input list, and the after list will be empty.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert split([6, 7, 8, 9], 0) == #([], [6, 7, 8, 9])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert split([6, 7, 8, 9], 2) == #([6, 7], [8, 9])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert split([6, 7, 8, 9], 4) == #([6, 7, 8, 9], [])\n"
" ```\n"
).
-spec split(list(ALR), integer()) -> {list(ALR), list(ALR)}.
split(List, Index) ->
split_loop(List, Index, []).
-file("src/gleeps/stdlib/list.gleam", 1475).
-spec split_while_loop(list(AME), fun((AME) -> boolean()), list(AME)) -> {list(AME),
list(AME)}.
split_while_loop(List, F, Acc) ->
case List of
[] ->
{lists:reverse(Acc), []};
[First | Rest] ->
case F(First) of
true ->
split_while_loop(Rest, F, [First | Acc]);
false ->
{lists:reverse(Acc), List}
end
end.
-file("src/gleeps/stdlib/list.gleam", 1468).
?DOC(
" Splits a list in two before the first element that a given function returns\n"
" `False` for.\n"
"\n"
" If the function returns `True` for all elements the first list will be the\n"
" input list, and the second list will be empty.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert split_while([1, 2, 3, 4, 5], fn(x) { x <= 3 })\n"
" == #([1, 2, 3], [4, 5])\n"
" ```\n"
"\n"
" ```gleam\n"
" assert split_while([1, 2, 3, 4, 5], fn(x) { x <= 5 })\n"
" == #([1, 2, 3, 4, 5], [])\n"
" ```\n"
).
-spec split_while(list(AMA), fun((AMA) -> boolean())) -> {list(AMA), list(AMA)}.
split_while(List, Predicate) ->
split_while_loop(List, Predicate, []).
-file("src/gleeps/stdlib/list.gleam", 1512).
?DOC(
" Given a list of 2-element tuples, finds the first tuple that has a given\n"
" key as the first element and returns the second element.\n"
"\n"
" If no tuple is found with the given key then `Error(Nil)` is returned.\n"
"\n"
" This function may be useful for interacting with Erlang code where lists of\n"
" tuples are common.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert key_find([#(\"a\", 0), #(\"b\", 1)], \"a\") == Ok(0)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert key_find([#(\"a\", 0), #(\"b\", 1)], \"b\") == Ok(1)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert key_find([#(\"a\", 0), #(\"b\", 1)], \"c\") == Error(Nil)\n"
" ```\n"
).
-spec key_find(list({AMJ, AMK}), AMJ) -> {ok, AMK} | {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
).
-file("src/gleeps/stdlib/list.gleam", 1541).
?DOC(
" Given a list of 2-element tuples, finds all tuples that have a given\n"
" key as the first element and returns the second element.\n"
"\n"
" This function may be useful for interacting with Erlang code where lists of\n"
" tuples are common.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert key_filter([#(\"a\", 0), #(\"b\", 1), #(\"a\", 2)], \"a\") == [0, 2]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert key_filter([#(\"a\", 0), #(\"b\", 1)], \"c\") == []\n"
" ```\n"
).
-spec key_filter(list({AMO, AMP}), AMO) -> list(AMP).
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
).
-file("src/gleeps/stdlib/list.gleam", 1581).
-spec key_pop_loop(list({AMY, AMZ}), AMY, list({AMY, AMZ})) -> {ok,
{AMZ, list({AMY, AMZ})}} |
{error, nil}.
key_pop_loop(List, Key, Checked) ->
case List of
[] ->
{error, nil};
[{K, V} | Rest] when K =:= Key ->
{ok, {V, lists:reverse(Checked, Rest)}};
[First | Rest@1] ->
key_pop_loop(Rest@1, Key, [First | Checked])
end.
-file("src/gleeps/stdlib/list.gleam", 1574).
?DOC(
" Given a list of 2-element tuples, finds the first tuple that has a given\n"
" key as the first element. This function will return the second element\n"
" of the found tuple and list with tuple removed.\n"
"\n"
" If no tuple is found with the given key then `Error(Nil)` is returned.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert key_pop([#(\"a\", 0), #(\"b\", 1)], \"a\") == Ok(#(0, [#(\"b\", 1)]))\n"
" ```\n"
"\n"
" ```gleam\n"
" assert key_pop([#(\"a\", 0), #(\"b\", 1)], \"b\") == Ok(#(1, [#(\"a\", 0)]))\n"
" ```\n"
"\n"
" ```gleam\n"
" assert key_pop([#(\"a\", 0), #(\"b\", 1)], \"c\") == Error(Nil)\n"
" ```\n"
).
-spec key_pop(list({AMS, AMT}), AMS) -> {ok, {AMT, list({AMS, AMT})}} |
{error, nil}.
key_pop(List, Key) ->
key_pop_loop(List, Key, []).
-file("src/gleeps/stdlib/list.gleam", 1613).
-spec key_set_loop(list({ANJ, ANK}), ANJ, ANK, list({ANJ, ANK})) -> list({ANJ,
ANK}).
key_set_loop(List, Key, Value, Inspected) ->
case List of
[{K, _} | Rest] when K =:= Key ->
lists:reverse(Inspected, [{K, Value} | Rest]);
[First | Rest@1] ->
key_set_loop(Rest@1, Key, Value, [First | Inspected]);
[] ->
lists:reverse([{Key, Value} | Inspected])
end.
-file("src/gleeps/stdlib/list.gleam", 1609).
?DOC(
" Given a list of 2-element tuples, inserts a key and value into the list.\n"
"\n"
" If there was already a tuple with the key then it is replaced, otherwise it\n"
" is added to the end of the list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert key_set([#(5, 0), #(4, 1)], 4, 100) == [#(5, 0), #(4, 100)]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert key_set([#(5, 0), #(4, 1)], 1, 100) == [#(5, 0), #(4, 1), #(1, 100)]\n"
" ```\n"
).
-spec key_set(list({ANF, ANG}), ANF, ANG) -> list({ANF, ANG}).
key_set(List, Key, Value) ->
key_set_loop(List, Key, Value, []).
-file("src/gleeps/stdlib/list.gleam", 1640).
?DOC(
" Calls a function for each element in a list, discarding the return value.\n"
"\n"
" Useful for calling a side effect for every item of a list.\n"
"\n"
" ```gleam\n"
" import gleam/io\n"
"\n"
" assert each([\"1\", \"2\", \"3\"], io.println) == Nil\n"
" // 1\n"
" // 2\n"
" // 3\n"
" ```\n"
).
-spec each(list(ANO), fun((ANO) -> any())) -> nil.
each(List, F) ->
case List of
[] ->
nil;
[First | Rest] ->
F(First),
each(Rest, F)
end.
-file("src/gleeps/stdlib/list.gleam", 1667).
?DOC(
" Calls a `Result` returning function for each element in a list, discarding\n"
" the return value. If the function returns `Error` then the iteration is\n"
" stopped and the error is returned.\n"
"\n"
" Useful for calling a side effect for every item of a list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert\n"
" try_each(\n"
" over: [1, 2, 3],\n"
" with: function_that_might_fail,\n"
" )\n"
" == Ok(Nil)\n"
" ```\n"
).
-spec try_each(list(ANR), fun((ANR) -> {ok, any()} | {error, ANU})) -> {ok, nil} |
{error, ANU}.
try_each(List, Fun) ->
case List of
[] ->
{ok, nil};
[First | Rest] ->
case Fun(First) of
{ok, _} ->
try_each(Rest, Fun);
{error, E} ->
{error, E}
end
end.
-file("src/gleeps/stdlib/list.gleam", 1699).
-spec partition_loop(list(BGP), fun((BGP) -> boolean()), list(BGP), list(BGP)) -> {list(BGP),
list(BGP)}.
partition_loop(List, Categorise, Trues, Falses) ->
case List of
[] ->
{lists:reverse(Trues), lists:reverse(Falses)};
[First | Rest] ->
case Categorise(First) of
true ->
partition_loop(Rest, Categorise, [First | Trues], Falses);
false ->
partition_loop(Rest, Categorise, Trues, [First | Falses])
end
end.
-file("src/gleeps/stdlib/list.gleam", 1692).
?DOC(
" Partitions a list into a tuple/pair of lists\n"
" by a given categorisation function.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" import gleam/int\n"
"\n"
" assert [1, 2, 3, 4, 5] |> partition(int.is_odd) == #([1, 3, 5], [2, 4])\n"
" ```\n"
).
-spec partition(list(ANZ), fun((ANZ) -> boolean())) -> {list(ANZ), list(ANZ)}.
partition(List, Categorise) ->
partition_loop(List, Categorise, [], []).
-file("src/gleeps/stdlib/list.gleam", 1743).
-spec permutation_prepend(
AOT,
list(list(AOT)),
list(AOT),
list(AOT),
list(list(AOT))
) -> list(list(AOT)).
permutation_prepend(El, Permutations, List_1, List_2, Acc) ->
case Permutations of
[] ->
permutation_zip(List_1, List_2, Acc);
[Head | Tail] ->
permutation_prepend(El, Tail, List_1, List_2, [[El | Head] | Acc])
end.
-file("src/gleeps/stdlib/list.gleam", 1725).
-spec permutation_zip(list(AOM), list(AOM), list(list(AOM))) -> list(list(AOM)).
permutation_zip(List, Rest, Acc) ->
case List of
[] ->
lists:reverse(Acc);
[Head | Tail] ->
permutation_prepend(
Head,
permutations(lists:reverse(Rest, Tail)),
Tail,
[Head | Rest],
Acc
)
end.
-file("src/gleeps/stdlib/list.gleam", 1718).
?DOC(
" Returns all the permutations of a list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert permutations([1, 2]) == [[1, 2], [2, 1]]\n"
" ```\n"
).
-spec permutations(list(AOI)) -> list(list(AOI)).
permutations(List) ->
case List of
[] ->
[[]];
L ->
permutation_zip(L, [], [])
end.
-file("src/gleeps/stdlib/list.gleam", 1776).
-spec window_loop(list(list(APG)), list(APG), integer()) -> list(list(APG)).
window_loop(Acc, List, N) ->
Window = take(List, N),
case erlang:length(Window) =:= N of
true ->
window_loop([Window | Acc], drop(List, 1), N);
false ->
lists:reverse(Acc)
end.
-file("src/gleeps/stdlib/list.gleam", 1769).
?DOC(
" Returns a list of sliding windows.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert window([1,2,3,4,5], 3) == [[1, 2, 3], [2, 3, 4], [3, 4, 5]]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert window([1, 2], 4) == []\n"
" ```\n"
).
-spec window(list(APC), integer()) -> list(list(APC)).
window(List, N) ->
case N =< 0 of
true ->
[];
false ->
window_loop([], List, N)
end.
-file("src/gleeps/stdlib/list.gleam", 1797).
?DOC(
" Returns a list of tuples containing two contiguous elements.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert window_by_2([1,2,3,4]) == [#(1, 2), #(2, 3), #(3, 4)]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert window_by_2([1]) == []\n"
" ```\n"
).
-spec window_by_2(list(APM)) -> list({APM, APM}).
window_by_2(List) ->
zip(List, drop(List, 1)).
-file("src/gleeps/stdlib/list.gleam", 1809).
?DOC(
" Drops the first elements in a given list for which the predicate function returns `True`.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert drop_while([1, 2, 3, 4], fn (x) { x < 3 }) == [3, 4]\n"
" ```\n"
).
-spec drop_while(list(APP), fun((APP) -> boolean())) -> list(APP).
drop_while(List, Predicate) ->
case List of
[] ->
[];
[First | Rest] ->
case Predicate(First) of
true ->
drop_while(Rest, Predicate);
false ->
[First | Rest]
end
end.
-file("src/gleeps/stdlib/list.gleam", 1838).
-spec take_while_loop(list(APV), fun((APV) -> boolean()), list(APV)) -> list(APV).
take_while_loop(List, Predicate, Acc) ->
case List of
[] ->
lists:reverse(Acc);
[First | Rest] ->
case Predicate(First) of
true ->
take_while_loop(Rest, Predicate, [First | Acc]);
false ->
lists:reverse(Acc)
end
end.
-file("src/gleeps/stdlib/list.gleam", 1831).
?DOC(
" Takes the first elements in a given list for which the predicate function returns `True`.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert take_while([1, 2, 3, 2, 4], fn (x) { x < 3 }) == [1, 2]\n"
" ```\n"
).
-spec take_while(list(APS), fun((APS) -> boolean())) -> list(APS).
take_while(List, Predicate) ->
take_while_loop(List, Predicate, []).
-file("src/gleeps/stdlib/list.gleam", 1870).
-spec chunk_loop(list(AQE), fun((AQE) -> AQG), AQG, list(AQE), list(list(AQE))) -> list(list(AQE)).
chunk_loop(List, F, Previous_key, Current_chunk, Acc) ->
case List of
[First | Rest] ->
Key = F(First),
case Key =:= Previous_key of
true ->
chunk_loop(Rest, F, Key, [First | Current_chunk], Acc);
false ->
New_acc = [lists:reverse(Current_chunk) | Acc],
chunk_loop(Rest, F, Key, [First], New_acc)
end;
[] ->
lists:reverse([lists:reverse(Current_chunk) | Acc])
end.
-file("src/gleeps/stdlib/list.gleam", 1863).
?DOC(
" Returns a list of chunks in which\n"
" the return value of calling `f` on each element is the same.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert [1, 2, 2, 3, 4, 4, 6, 7, 7] |> chunk(by: fn(n) { n % 2 })\n"
" == [[1], [2, 2], [3], [4, 4, 6], [7, 7]]\n"
" ```\n"
).
-spec chunk(list(APZ), fun((APZ) -> any())) -> list(list(APZ)).
chunk(List, F) ->
case List of
[] ->
[];
[First | Rest] ->
chunk_loop(Rest, F, F(First), [First], [])
end.
-file("src/gleeps/stdlib/list.gleam", 1915).
-spec sized_chunk_loop(
list(AQQ),
integer(),
integer(),
list(AQQ),
list(list(AQQ))
) -> list(list(AQQ)).
sized_chunk_loop(List, Count, Left, Current_chunk, Acc) ->
case List of
[] ->
case Current_chunk of
[] ->
lists:reverse(Acc);
Remaining ->
lists:reverse([lists:reverse(Remaining) | Acc])
end;
[First | Rest] ->
Chunk = [First | Current_chunk],
case Left > 1 of
true ->
sized_chunk_loop(Rest, Count, Left - 1, Chunk, Acc);
false ->
sized_chunk_loop(
Rest,
Count,
Count,
[],
[lists:reverse(Chunk) | Acc]
)
end
end.
-file("src/gleeps/stdlib/list.gleam", 1911).
?DOC(
" Returns a list of chunks containing `count` elements each.\n"
"\n"
" If the last chunk does not have `count` elements, it is instead\n"
" a partial chunk, with less than `count` elements.\n"
"\n"
" For any `count` less than 1 this function behaves as if it was set to 1.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert [1, 2, 3, 4, 5, 6] |> sized_chunk(into: 2)\n"
" == [[1, 2], [3, 4], [5, 6]]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert [1, 2, 3, 4, 5, 6, 7, 8] |> sized_chunk(into: 3)\n"
" == [[1, 2, 3], [4, 5, 6], [7, 8]]\n"
" ```\n"
).
-spec sized_chunk(list(AQM), integer()) -> list(list(AQM)).
sized_chunk(List, Count) ->
sized_chunk_loop(List, Count, Count, [], []).
-file("src/gleeps/stdlib/list.gleam", 1957).
?DOC(
" This function acts similar to fold, but does not take an initial state.\n"
" Instead, it starts from the first element in the list\n"
" and combines it with each subsequent element in turn using the given\n"
" function. The function is called as `fun(accumulator, current_element)`.\n"
"\n"
" Returns `Ok` to indicate a successful run, and `Error` if called on an\n"
" empty list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert [] |> reduce(fn(acc, x) { acc + x }) == Error(Nil)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert [1, 2, 3, 4, 5] |> reduce(fn(acc, x) { acc + x }) == Ok(15)\n"
" ```\n"
).
-spec reduce(list(AQX), fun((AQX, AQX) -> AQX)) -> {ok, AQX} | {error, nil}.
reduce(List, Fun) ->
case List of
[] ->
{error, nil};
[First | Rest] ->
{ok, fold(Rest, First, Fun)}
end.
-file("src/gleeps/stdlib/list.gleam", 1981).
-spec scan_loop(list(ARF), ARH, list(ARH), fun((ARH, ARF) -> ARH)) -> list(ARH).
scan_loop(List, Accumulator, Accumulated, Fun) ->
case List of
[] ->
lists:reverse(Accumulated);
[First | Rest] ->
Next = Fun(Accumulator, First),
scan_loop(Rest, Next, [Next | Accumulated], Fun)
end.
-file("src/gleeps/stdlib/list.gleam", 1973).
?DOC(
" Similar to `fold`, but yields the state of the accumulator at each stage.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert scan(over: [1, 2, 3], from: 100, with: fn(acc, i) { acc + i })\n"
" == [101, 103, 106]\n"
" ```\n"
).
-spec scan(list(ARB), ARD, fun((ARD, ARB) -> ARD)) -> list(ARD).
scan(List, Initial, Fun) ->
scan_loop(List, Initial, [], Fun).
-file("src/gleeps/stdlib/list.gleam", 2012).
?DOC(
" Returns the last element in the given list.\n"
"\n"
" Returns `Error(Nil)` if the list is empty.\n"
"\n"
" This function runs in linear time.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert last([]) == Error(Nil)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert last([1, 2, 3, 4, 5]) == Ok(5)\n"
" ```\n"
).
-spec last(list(ARK)) -> {ok, ARK} | {error, nil}.
last(List) ->
case List of
[] ->
{error, nil};
[Last] ->
{ok, Last};
[_ | Rest] ->
last(Rest)
end.
-file("src/gleeps/stdlib/list.gleam", 2033).
?DOC(
" Return unique combinations of elements in the list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert combinations([1, 2, 3], 2) == [[1, 2], [1, 3], [2, 3]]\n"
" ```\n"
"\n"
" ```gleam\n"
" assert combinations([1, 2, 3, 4], 3)\n"
" == [[1, 2, 3], [1, 2, 4], [1, 3, 4], [2, 3, 4]]\n"
" ```\n"
).
-spec combinations(list(ARO), integer()) -> list(list(ARO)).
combinations(Items, N) ->
case {N, Items} of
{0, _} ->
[[]];
{_, []} ->
[];
{_, [First | Rest]} ->
_pipe = Rest,
_pipe@1 = combinations(_pipe, N - 1),
_pipe@2 = map(
_pipe@1,
fun(Combination) -> [First | Combination] end
),
_pipe@3 = lists:reverse(_pipe@2),
fold(_pipe@3, combinations(Rest, N), fun(Acc, C) -> [C | Acc] end)
end.
-file("src/gleeps/stdlib/list.gleam", 2058).
-spec combination_pairs_loop(list(ARV), list({ARV, ARV})) -> list({ARV, ARV}).
combination_pairs_loop(Items, Acc) ->
case Items of
[] ->
lists:reverse(Acc);
[First | Rest] ->
First_combinations = map(Rest, fun(Other) -> {First, Other} end),
Acc@1 = lists:reverse(First_combinations, Acc),
combination_pairs_loop(Rest, Acc@1)
end.
-file("src/gleeps/stdlib/list.gleam", 2054).
?DOC(
" Return unique pair combinations of elements in the list.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert combination_pairs([1, 2, 3]) == [#(1, 2), #(1, 3), #(2, 3)]\n"
" ```\n"
).
-spec combination_pairs(list(ARS)) -> list({ARS, ARS}).
combination_pairs(Items) ->
combination_pairs_loop(Items, []).
-file("src/gleeps/stdlib/list.gleam", 2117).
-spec take_firsts(list(list(ASP)), list(ASP), list(list(ASP))) -> {list(ASP),
list(list(ASP))}.
take_firsts(Rows, Column, Remaining_rows) ->
case Rows of
[] ->
{lists:reverse(Column), lists:reverse(Remaining_rows)};
[[] | Rest] ->
take_firsts(Rest, Column, Remaining_rows);
[[First | Remaining_row] | Rest_rows] ->
Remaining_rows@1 = [Remaining_row | Remaining_rows],
take_firsts(Rest_rows, [First | Column], Remaining_rows@1)
end.
-file("src/gleeps/stdlib/list.gleam", 2101).
-spec transpose_loop(list(list(ASI)), list(list(ASI))) -> list(list(ASI)).
transpose_loop(Rows, Columns) ->
case Rows of
[] ->
lists:reverse(Columns);
_ ->
{Column, Rest} = take_firsts(Rows, [], []),
case Column of
[_ | _] ->
transpose_loop(Rest, [Column | Columns]);
[] ->
transpose_loop(Rest, Columns)
end
end.
-file("src/gleeps/stdlib/list.gleam", 2097).
?DOC(
" Transpose rows and columns of the list of lists.\n"
"\n"
" Notice: This function is not tail recursive,\n"
" and thus may exceed stack size if called,\n"
" with large lists (on the JavaScript target).\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert transpose([[1, 2, 3], [101, 102, 103]])\n"
" == [[1, 101], [2, 102], [3, 103]]\n"
" ```\n"
).
-spec transpose(list(list(ASD))) -> list(list(ASD)).
transpose(List_of_lists) ->
transpose_loop(List_of_lists, []).
-file("src/gleeps/stdlib/list.gleam", 2078).
?DOC(
" Make a list alternating the elements from the given lists\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert interleave([[1, 2], [101, 102], [201, 202]])\n"
" == [1, 101, 201, 2, 102, 202]\n"
" ```\n"
).
-spec interleave(list(list(ARZ))) -> list(ARZ).
interleave(List) ->
_pipe = List,
_pipe@1 = transpose(_pipe),
lists:append(_pipe@1).
-file("src/gleeps/stdlib/list.gleam", 2150).
-spec shuffle_pair_unwrap_loop(list({float(), ATB}), list(ATB)) -> list(ATB).
shuffle_pair_unwrap_loop(List, Acc) ->
case List of
[] ->
Acc;
[Elem_pair | Enumerable] ->
shuffle_pair_unwrap_loop(
Enumerable,
[erlang:element(2, Elem_pair) | Acc]
)
end.
-file("src/gleeps/stdlib/list.gleam", 2158).
-spec do_shuffle_by_pair_indexes(list({float(), ATF})) -> list({float(), ATF}).
do_shuffle_by_pair_indexes(List_of_pairs) ->
sort(
List_of_pairs,
fun(A_pair, B_pair) ->
gleeps@stdlib@float:compare(
erlang:element(1, A_pair),
erlang:element(1, B_pair)
)
end
).
-file("src/gleeps/stdlib/list.gleam", 2143).
?DOC(
" Takes a list, randomly sorts all items and returns the shuffled list.\n"
"\n"
" This function uses `float.random` to decide the order of the elements.\n"
"\n"
" ## Example\n"
"\n"
" ```gleam\n"
" [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] |> shuffle\n"
" // -> [1, 6, 9, 10, 3, 8, 4, 2, 7, 5]\n"
" ```\n"
).
-spec shuffle(list(ASY)) -> list(ASY).
shuffle(List) ->
_pipe = List,
_pipe@1 = fold(_pipe, [], fun(Acc, A) -> [{rand:uniform(), A} | Acc] end),
_pipe@2 = do_shuffle_by_pair_indexes(_pipe@1),
shuffle_pair_unwrap_loop(_pipe@2, []).
-file("src/gleeps/stdlib/list.gleam", 2188).
-spec max_loop(list(ATP), fun((ATP, ATP) -> gleeps@stdlib@order:order()), ATP) -> ATP.
max_loop(List, Compare, Max) ->
case List of
[] ->
Max;
[First | Rest] ->
case Compare(First, Max) of
gt ->
max_loop(Rest, Compare, First);
lt ->
max_loop(Rest, Compare, Max);
eq ->
max_loop(Rest, Compare, Max)
end
end.
-file("src/gleeps/stdlib/list.gleam", 2178).
?DOC(
" Takes a list and a comparator, and returns the maximum element in the list\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" assert [1, 2, 3, 4, 5] |> list.max(int.compare) == Ok(5)\n"
" ```\n"
"\n"
" ```gleam\n"
" assert [\"a\", \"c\", \"b\"] |> list.max(string.compare) == Ok(\"c\")\n"
" ```\n"
).
-spec max(list(ATI), fun((ATI, ATI) -> gleeps@stdlib@order:order())) -> {ok,
ATI} |
{error, nil}.
max(List, Compare) ->
case List of
[] ->
{error, nil};
[First | Rest] ->
{ok, max_loop(Rest, Compare, First)}
end.
-file("src/gleeps/stdlib/list.gleam", 2253).
-spec log_random() -> float().
log_random() ->
Random@1 = case gleeps@stdlib@float:logarithm(
rand:uniform() + 2.2250738585072014e-308
) of
{ok, Random} -> Random;
_assert_fail ->
erlang:error(#{gleam_error => let_assert,
message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
file => <<?FILEPATH/utf8>>,
module => <<"gleeps/stdlib/list"/utf8>>,
function => <<"log_random"/utf8>>,
line => 2254,
value => _assert_fail,
start => 55184,
'end' => 55255,
pattern_start => 55195,
pattern_end => 55205})
end,
Random@1.
-file("src/gleeps/stdlib/list.gleam", 2230).
-spec sample_loop(
list(ATT),
gleeps@stdlib@dict:dict(integer(), ATT),
integer(),
float()
) -> gleeps@stdlib@dict:dict(integer(), ATT).
sample_loop(List, Reservoir, N, W) ->
Skip = begin
Log@1 = case gleeps@stdlib@float:logarithm(1.0 - W) of
{ok, Log} -> Log;
_assert_fail ->
erlang:error(#{gleam_error => let_assert,
message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
file => <<?FILEPATH/utf8>>,
module => <<"gleeps/stdlib/list"/utf8>>,
function => <<"sample_loop"/utf8>>,
line => 2237,
value => _assert_fail,
start => 54745,
'end' => 54791,
pattern_start => 54756,
pattern_end => 54763})
end,
erlang:round(math:floor(case Log@1 of
+0.0 -> +0.0;
-0.0 -> -0.0;
Gleam@denominator -> log_random() / Gleam@denominator
end))
end,
case drop(List, Skip) of
[] ->
Reservoir;
[First | Rest] ->
Reservoir@1 = gleeps@stdlib@dict:insert(
Reservoir,
gleeps@stdlib@int:random(N),
First
),
W@1 = W * math:exp(case erlang:float(N) of
+0.0 -> +0.0;
-0.0 -> -0.0;
Gleam@denominator@1 -> log_random() / Gleam@denominator@1
end),
sample_loop(Rest, Reservoir@1, N, W@1)
end.
-file("src/gleeps/stdlib/list.gleam", 2272).
-spec build_reservoir_loop(
list(AUE),
integer(),
gleeps@stdlib@dict:dict(integer(), AUE)
) -> {gleeps@stdlib@dict:dict(integer(), AUE), list(AUE)}.
build_reservoir_loop(List, Size, Reservoir) ->
Reservoir_size = maps:size(Reservoir),
case Reservoir_size >= Size of
true ->
{Reservoir, List};
false ->
case List of
[] ->
{Reservoir, []};
[First | Rest] ->
Reservoir@1 = gleeps@stdlib@dict:insert(
Reservoir,
Reservoir_size,
First
),
build_reservoir_loop(Rest, Size, Reservoir@1)
end
end.
-file("src/gleeps/stdlib/list.gleam", 2265).
?DOC(
" Builds the initial reservoir used by Algorithm L.\n"
" This is a dictionary with keys ranging from `0` up to `n - 1` where each\n"
" value is the corresponding element at that position in `list`.\n"
"\n"
" This also returns the remaining elements of `list` that didn't end up in\n"
" the reservoir.\n"
).
-spec build_reservoir(list(ATZ), integer()) -> {gleeps@stdlib@dict:dict(integer(), ATZ),
list(ATZ)}.
build_reservoir(List, N) ->
build_reservoir_loop(List, N, maps:new()).
-file("src/gleeps/stdlib/list.gleam", 2212).
?DOC(
" Returns a random sample of up to n elements from a list using reservoir\n"
" sampling via [Algorithm L](https://en.wikipedia.org/wiki/Reservoir_sampling#Optimal:_Algorithm_L).\n"
" Returns an empty list if the sample size is less than or equal to 0.\n"
"\n"
" Order is not random, only selection is.\n"
"\n"
" ## Examples\n"
"\n"
" ```gleam\n"
" sample([1, 2, 3, 4, 5], 3)\n"
" // -> [2, 4, 5] // A random sample of 3 items\n"
" ```\n"
).
-spec sample(list(ATQ), integer()) -> list(ATQ).
sample(List, N) ->
{Reservoir, Rest} = build_reservoir(List, N),
case gleeps@stdlib@dict:is_empty(Reservoir) of
true ->
[];
false ->
W = math:exp(case erlang:float(N) of
+0.0 -> +0.0;
-0.0 -> -0.0;
Gleam@denominator -> log_random() / Gleam@denominator
end),
maps:values(sample_loop(Rest, Reservoir, N, W))
end.