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-module(lc_warnings).
-compile([export_all]).
close(Fs) ->
%% There should be a warning since we ignore a potential
%% {error,Error} return from file:close/1.
[file:close(F) || F <- Fs],
%% No warning because the type of unmatched return will be ['ok']
%% (which is a list of a simple type).
[ok = file:close(F) || F <- Fs],
%% Suppressed.
_ = [file:close(F) || F <- Fs],
ok.
format(X) ->
%% No warning since the result of the list comprehension is
%% a list of simple.
[io:format("~p\n", [E]) || E <- X],
%% Warning explicitly suppressed.
_ = [io:format("~p\n", [E]) || E <- X],
ok.
opaque1() ->
List = gen_atom(),
%% This is a list of an externally defined opaque type. Since
%% we are not allowed to peek inside opaque types, there should
%% be a warning (even though the type in this case happens to be
%% an atom).
[E || E <- List],
%% Suppressed.
_ = [E || E <- List],
ok.
opaque2() ->
List = gen_array(),
%% This is an list of an externally defined opaque type. Since
%% we are not allowed to peek inside opaque types, there should
%% be a warning.
[E || E <- List],
%% Suppressed.
_ = [E || E <- List],
ok.
opaque3() ->
List = gen_int(),
%% No warning, since we are allowed to look into the type and can
%% see that it is a simple type.
[E || E <- List],
%% Suppressed.
_ = [E || E <- List],
ok.
opaque4() ->
List = gen_tuple(),
%% There should be a warning, since we are allowed to look inside
%% the opaque type and see that it is a tuple (non-simple).
[E || E <- List],
%% Suppressed.
_ = [E || E <- List],
ok.
gen_atom() ->
[opaque_atom_adt:atom(ok)].
gen_array() ->
[array:new()].
gen_int() ->
[opaque_int(42)].
gen_tuple() ->
[opaque_tuple(x, 25)].
-opaque opaque_int() :: integer().
-spec opaque_int(integer()) -> opaque_int().
opaque_int(Int) -> Int.
-opaque opaque_tuple() :: {any(),any()}.
-spec opaque_tuple(any(), any()) -> opaque_tuple().
opaque_tuple(X, Y) ->
{X,Y}.
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