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gleam_stdlib gen src gleam@option.erl
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gen/src/gleam@option.erl

-module(gleam@option).
-compile(no_auto_import).
-export([all/1, is_some/1, is_none/1, to_result/2, from_result/1, unwrap/2, map/2, flatten/1, then/2, 'or'/2, values/1]).
-export_type([option/1]).
-type option(DHR) :: {some, DHR} | none.
-spec all(list(option(DHS))) -> option(list(DHS)).
all(List) ->
gleam@list:fold_right(
List,
{some, []},
fun(Item, Acc) -> case {Acc, Item} of
{{some, Values}, {some, Value}} ->
{some, [Value | Values]};
{_, _} ->
none
end end
).
-spec is_some(option(any())) -> boolean().
is_some(Option) ->
Option /= none.
-spec is_none(option(any())) -> boolean().
is_none(Option) ->
Option =:= none.
-spec to_result(option(DIB), DIE) -> {ok, DIB} | {error, DIE}.
to_result(Option, E) ->
case Option of
{some, A} ->
{ok, A};
_ ->
{error, E}
end.
-spec from_result({ok, DIH} | {error, any()}) -> option(DIH).
from_result(Result) ->
case Result of
{ok, A} ->
{some, A};
_ ->
none
end.
-spec unwrap(option(DIM), DIM) -> DIM.
unwrap(Option, Default) ->
case Option of
{some, X} ->
X;
none ->
Default
end.
-spec map(option(DIO), fun((DIO) -> DIQ)) -> option(DIQ).
map(Option, Fun) ->
case Option of
{some, X} ->
{some, Fun(X)};
none ->
none
end.
-spec flatten(option(option(DIS))) -> option(DIS).
flatten(Option) ->
case Option of
{some, X} ->
X;
none ->
none
end.
-spec then(option(DIW), fun((DIW) -> option(DIY))) -> option(DIY).
then(Option, Fun) ->
case Option of
{some, X} ->
Fun(X);
none ->
none
end.
-spec 'or'(option(DJB), option(DJB)) -> option(DJB).
'or'(First, Second) ->
case First of
{some, _} ->
First;
none ->
Second
end.
-spec values(list(option(DJF))) -> list(DJF).
values(Options) ->
gleam@list:filter_map(Options, fun(Op) -> to_result(Op, <<""/utf8>>) end).