-module(gleam@result).
-compile(no_auto_import).

-export([is_ok/1, is_error/1, map/2, map_error/2, flatten/1, then/2, unwrap/2, nil_error/1, 'or'/2]).

is_ok(Result) ->
    case Result of
        {error, _} ->
            false;

        {ok, _} ->
            true
    end.

is_error(Result) ->
    case Result of
        {ok, _} ->
            false;

        {error, _} ->
            true
    end.

map(Result, Fun) ->
    case Result of
        {ok, X} ->
            {ok, Fun(X)};

        {error, E} ->
            {error, E}
    end.

map_error(Result, Fun) ->
    case Result of
        {ok, X} ->
            {ok, X};

        {error, Error} ->
            {error, Fun(Error)}
    end.

flatten(Result) ->
    case Result of
        {ok, X} ->
            X;

        {error, Error} ->
            {error, Error}
    end.

then(Result, Fun) ->
    case Result of
        {ok, X} ->
            Fun(X);

        {error, E} ->
            {error, E}
    end.

unwrap(Result, Default) ->
    case Result of
        {ok, V} ->
            V;

        {error, _} ->
            Default
    end.

nil_error(Result) ->
    map_error(Result, fun(_) -> nil end).

'or'(First, Second) ->
    case First of
        {ok, _} ->
            First;

        {error, _} ->
            Second
    end.