LibGUI+Userland: Stop returning Layout from `Widget::(try_)set_layout()`

Nobody uses this return value any more. It also lets us remove a whole
bunch of `(void)` casts. :^)

Base/res/devel/templates/serenity-application/main.cpp

@@ -23,7 +23,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     auto main_widget = TRY(window->set_main_widget<GUI::Widget>());
     main_widget->set_fill_with_background_color(true);
 
-    (void)TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>(16));
+    TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>(16));
 
     auto button = TRY(main_widget->try_add<GUI::Button>("Click me!"));
     button->on_click = [&](auto) {

Userland/Applications/CrashReporter/main.cpp

@@ -216,7 +216,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     auto& tab_widget = *widget->find_descendant_of_type_named<GUI::TabWidget>("tab_widget");
 
     auto backtrace_tab = TRY(tab_widget.try_add_tab<GUI::Widget>("Backtrace"));
-    (void)TRY(backtrace_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
+    TRY(backtrace_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
 
     auto backtrace_label = TRY(backtrace_tab->try_add<GUI::Label>("A backtrace for each thread alive during the crash is listed below:"));
     backtrace_label->set_text_alignment(Gfx::TextAlignment::CenterLeft);
@@ -236,7 +236,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     cpu_registers_tab_widget->set_tab_position(GUI::TabWidget::TabPosition::Bottom);
 
     auto environment_tab = TRY(tab_widget.try_add_tab<GUI::Widget>("Environment"));
-    (void)TRY(environment_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
+    TRY(environment_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
 
     auto environment_text_editor = TRY(environment_tab->try_add<GUI::TextEditor>());
     environment_text_editor->set_text(DeprecatedString::join('\n', environment));
@@ -245,7 +245,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     environment_text_editor->set_should_hide_unnecessary_scrollbars(true);
 
     auto memory_regions_tab = TRY(tab_widget.try_add_tab<GUI::Widget>("Memory Regions"));
-    (void)TRY(memory_regions_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
+    TRY(memory_regions_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
 
     auto memory_regions_text_editor = TRY(memory_regions_tab->try_add<GUI::TextEditor>());
     memory_regions_text_editor->set_text(DeprecatedString::join('\n', memory_regions));
@@ -303,7 +303,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
         [&](auto results) -> ErrorOr<void> {
             for (auto& backtrace : results.thread_backtraces) {
                 auto container = TRY(backtrace_tab_widget->try_add_tab<GUI::Widget>(backtrace.title));
-                (void)TRY(container->template try_set_layout<GUI::VerticalBoxLayout>(4));
+                TRY(container->template try_set_layout<GUI::VerticalBoxLayout>(4));
                 auto backtrace_text_editor = TRY(container->template try_add<GUI::TextEditor>());
                 backtrace_text_editor->set_text(backtrace.text);
                 backtrace_text_editor->set_mode(GUI::TextEditor::Mode::ReadOnly);
@@ -314,7 +314,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
 
             for (auto& cpu_registers : results.thread_cpu_registers) {
                 auto container = TRY(cpu_registers_tab_widget->try_add_tab<GUI::Widget>(cpu_registers.title));
-                (void)TRY(container->template try_set_layout<GUI::VerticalBoxLayout>(4));
+                TRY(container->template try_set_layout<GUI::VerticalBoxLayout>(4));
                 auto cpu_registers_text_editor = TRY(container->template try_add<GUI::TextEditor>());
                 cpu_registers_text_editor->set_text(cpu_registers.text);
                 cpu_registers_text_editor->set_mode(GUI::TextEditor::Mode::ReadOnly);

Userland/Applications/FileManager/PropertiesWindow.cpp

@@ -53,7 +53,7 @@ PropertiesWindow::PropertiesWindow(DeprecatedString const& path, Window* parent_
 ErrorOr<void> PropertiesWindow::create_widgets(bool disable_rename)
 {
     auto main_widget = TRY(set_main_widget<GUI::Widget>());
-    (void)TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>(4, 6));
+    TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>(4, 6));
     main_widget->set_fill_with_background_color(true);
 
     auto tab_widget = TRY(main_widget->try_add<GUI::TabWidget>());
@@ -149,7 +149,7 @@ ErrorOr<void> PropertiesWindow::create_widgets(bool disable_rename)
     TRY(setup_permission_checkboxes(*others_read, *others_write, *others_execute, { S_IROTH, S_IWOTH, S_IXOTH }, m_mode));
 
     auto button_widget = TRY(main_widget->try_add<GUI::Widget>());
-    (void)TRY(button_widget->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins {}, 5));
+    TRY(button_widget->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins {}, 5));
     button_widget->set_fixed_height(22);
 
     TRY(button_widget->add_spacer());

Userland/Applications/FileManager/main.cpp

@@ -358,7 +358,7 @@ ErrorOr<int> run_in_desktop_mode()
     window->set_has_alpha_channel(true);
 
     auto desktop_widget = TRY(window->set_main_widget<FileManager::DesktopWidget>());
-    (void)TRY(desktop_widget->try_set_layout<GUI::VerticalBoxLayout>());
+    TRY(desktop_widget->try_set_layout<GUI::VerticalBoxLayout>());
 
     auto directory_view = TRY(desktop_widget->try_add<DirectoryView>(DirectoryView::Mode::Desktop));
     directory_view->set_name("directory_view");

Userland/Applications/Piano/MainWidget.cpp

@@ -34,7 +34,7 @@ MainWidget::MainWidget(TrackManager& track_manager, AudioPlayerLoop& loop)
 
 ErrorOr<void> MainWidget::initialize()
 {
-    (void)TRY(try_set_layout<GUI::VerticalBoxLayout>(2, 2));
+    TRY(try_set_layout<GUI::VerticalBoxLayout>(2, 2));
     set_fill_with_background_color(true);
 
     m_wave_widget = TRY(try_add<WaveWidget>(m_track_manager));
@@ -49,7 +49,7 @@ ErrorOr<void> MainWidget::initialize()
     m_player_widget = TRY(try_add<PlayerWidget>(m_track_manager, m_audio_loop));
 
     m_keys_and_knobs_container = TRY(try_add<GUI::Widget>());
-    (void)TRY(m_keys_and_knobs_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins {}, 2));
+    TRY(m_keys_and_knobs_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins {}, 2));
     m_keys_and_knobs_container->set_fixed_height(130);
     m_keys_and_knobs_container->set_fill_with_background_color(true);
 

Userland/Applications/Piano/PlayerWidget.cpp

@@ -39,7 +39,7 @@ PlayerWidget::PlayerWidget(TrackManager& manager, AudioPlayerLoop& loop)
 
 ErrorOr<void> PlayerWidget::initialize()
 {
-    (void)TRY(try_set_layout<GUI::HorizontalBoxLayout>());
+    TRY(try_set_layout<GUI::HorizontalBoxLayout>());
     set_fill_with_background_color(true);
     TRY(m_track_number_choices.try_append("1"));
 

Userland/Applications/PixelPaint/Filters/Bloom.cpp

@@ -38,7 +38,7 @@ ErrorOr<RefPtr<GUI::Widget>> Bloom::get_settings_widget()
 {
     if (!m_settings_widget) {
         auto settings_widget = TRY(GUI::Widget::try_create());
-        (void)TRY(settings_widget->try_set_layout<GUI::VerticalBoxLayout>());
+        TRY(settings_widget->try_set_layout<GUI::VerticalBoxLayout>());
 
         auto name_label = TRY(settings_widget->try_add<GUI::Label>("Bloom Filter"));
         name_label->set_font_weight(Gfx::FontWeight::Bold);
@@ -47,7 +47,7 @@ ErrorOr<RefPtr<GUI::Widget>> Bloom::get_settings_widget()
 
         auto luma_lower_container = TRY(settings_widget->try_add<GUI::Widget>());
         luma_lower_container->set_fixed_height(50);
-        (void)TRY(luma_lower_container->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
+        TRY(luma_lower_container->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
 
         auto luma_lower_label = TRY(luma_lower_container->try_add<GUI::Label>("Luma lower bound:"));
         luma_lower_label->set_text_alignment(Gfx::TextAlignment::CenterLeft);
@@ -63,7 +63,7 @@ ErrorOr<RefPtr<GUI::Widget>> Bloom::get_settings_widget()
 
         auto radius_container = TRY(settings_widget->try_add<GUI::Widget>());
         radius_container->set_fixed_height(50);
-        (void)TRY(radius_container->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
+        TRY(radius_container->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
 
         auto radius_label = TRY(radius_container->try_add<GUI::Label>("Blur Radius:"));
         radius_label->set_text_alignment(Gfx::TextAlignment::CenterLeft);

Userland/Applications/PixelPaint/Filters/FastBoxBlur.cpp

@@ -40,7 +40,7 @@ ErrorOr<RefPtr<GUI::Widget>> FastBoxBlur::get_settings_widget()
 {
     if (!m_settings_widget) {
         auto settings_widget = TRY(GUI::Widget::try_create());
-        (void)TRY(settings_widget->try_set_layout<GUI::VerticalBoxLayout>());
+        TRY(settings_widget->try_set_layout<GUI::VerticalBoxLayout>());
 
         auto name_label = TRY(settings_widget->try_add<GUI::Label>("Fast Box Blur Filter"));
         name_label->set_font_weight(Gfx::FontWeight::Bold);
@@ -86,7 +86,7 @@ ErrorOr<RefPtr<GUI::Widget>> FastBoxBlur::get_settings_widget()
 
         m_radius_container = TRY(settings_widget->try_add<GUI::Widget>());
         m_radius_container->set_fixed_height(20);
-        (void)TRY(m_radius_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
+        TRY(m_radius_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
 
         auto radius_label = TRY(m_radius_container->try_add<GUI::Label>("Radius:"));
         radius_label->set_text_alignment(Gfx::TextAlignment::CenterLeft);
@@ -103,7 +103,7 @@ ErrorOr<RefPtr<GUI::Widget>> FastBoxBlur::get_settings_widget()
         m_asymmetric_radius_container = TRY(settings_widget->try_add<GUI::Widget>());
         m_asymmetric_radius_container->set_visible(false);
         m_asymmetric_radius_container->set_fixed_height(50);
-        (void)TRY(m_asymmetric_radius_container->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
+        TRY(m_asymmetric_radius_container->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
 
         auto radius_x_container = TRY(m_asymmetric_radius_container->try_add<GUI::Widget>());
         radius_x_container->set_fixed_height(20);
@@ -123,7 +123,7 @@ ErrorOr<RefPtr<GUI::Widget>> FastBoxBlur::get_settings_widget()
 
         auto radius_y_container = TRY(m_asymmetric_radius_container->try_add<GUI::Widget>());
         radius_y_container->set_fixed_height(20);
-        (void)TRY(radius_y_container->try_set_layout<GUI::HorizontalBoxLayout>());
+        TRY(radius_y_container->try_set_layout<GUI::HorizontalBoxLayout>());
 
         auto radius_y_label = TRY(radius_y_container->try_add<GUI::Label>("Radius Y:"));
         radius_y_label->set_text_alignment(Gfx::TextAlignment::CenterLeft);
@@ -140,11 +140,11 @@ ErrorOr<RefPtr<GUI::Widget>> FastBoxBlur::get_settings_widget()
         m_vector_container = TRY(settings_widget->try_add<GUI::Widget>());
         m_vector_container->set_visible(false);
         m_vector_container->set_fixed_height(50);
-        (void)TRY(m_vector_container->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
+        TRY(m_vector_container->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
 
         auto angle_container = TRY(m_vector_container->try_add<GUI::Widget>());
         angle_container->set_fixed_height(20);
-        (void)TRY(angle_container->try_set_layout<GUI::HorizontalBoxLayout>());
+        TRY(angle_container->try_set_layout<GUI::HorizontalBoxLayout>());
 
         auto angle_label = TRY(angle_container->try_add<GUI::Label>("Angle:"));
         angle_label->set_text_alignment(Gfx::TextAlignment::CenterLeft);
@@ -160,7 +160,7 @@ ErrorOr<RefPtr<GUI::Widget>> FastBoxBlur::get_settings_widget()
 
         auto magnitude_container = TRY(m_vector_container->try_add<GUI::Widget>());
         magnitude_container->set_fixed_height(20);
-        (void)TRY(magnitude_container->try_set_layout<GUI::HorizontalBoxLayout>());
+        TRY(magnitude_container->try_set_layout<GUI::HorizontalBoxLayout>());
 
         auto magnitude_label = TRY(magnitude_container->try_add<GUI::Label>("Magnitude:"));
         magnitude_label->set_text_alignment(Gfx::TextAlignment::CenterLeft);
@@ -176,7 +176,7 @@ ErrorOr<RefPtr<GUI::Widget>> FastBoxBlur::get_settings_widget()
 
         auto gaussian_container = TRY(settings_widget->try_add<GUI::Widget>());
         gaussian_container->set_fixed_height(20);
-        (void)TRY(gaussian_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
+        TRY(gaussian_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
 
         m_gaussian_checkbox = TRY(gaussian_container->try_add<GUI::CheckBox>(TRY(String::from_utf8("Approximate Gaussian Blur"sv))));
         m_gaussian_checkbox->set_checked(m_approximate_gauss);

Userland/Applications/PixelPaint/Filters/Sepia.cpp

@@ -21,7 +21,7 @@ ErrorOr<RefPtr<GUI::Widget>> Sepia::get_settings_widget()
 {
     if (!m_settings_widget) {
         auto settings_widget = TRY(GUI::Widget::try_create());
-        (void)TRY(settings_widget->try_set_layout<GUI::VerticalBoxLayout>());
+        TRY(settings_widget->try_set_layout<GUI::VerticalBoxLayout>());
 
         auto name_label = TRY(settings_widget->try_add<GUI::Label>("Sepia Filter"));
         name_label->set_font_weight(Gfx::FontWeight::Bold);
@@ -30,7 +30,7 @@ ErrorOr<RefPtr<GUI::Widget>> Sepia::get_settings_widget()
 
         auto amount_container = TRY(settings_widget->try_add<GUI::Widget>());
         amount_container->set_fixed_height(20);
-        (void)TRY(amount_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
+        TRY(amount_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins { 4, 0, 4, 0 }));
 
         auto amount_label = TRY(amount_container->try_add<GUI::Label>("Amount:"));
         amount_label->set_text_alignment(Gfx::TextAlignment::CenterLeft);

Userland/Applications/PixelPaint/Tools/GradientTool.cpp

@@ -214,7 +214,7 @@ ErrorOr<GUI::Widget*> GradientTool::get_properties_widget()
 
         auto button_container = TRY(properties_widget->try_add<GUI::Widget>());
         button_container->set_fixed_height(22);
-        (void)TRY(button_container->try_set_layout<GUI::HorizontalBoxLayout>());
+        TRY(button_container->try_set_layout<GUI::HorizontalBoxLayout>());
         button_container->add_spacer().release_value_but_fixme_should_propagate_errors();
 
         auto apply_button = TRY(button_container->try_add<GUI::DialogButton>(String::from_utf8_short_string("Apply"sv)));

Userland/Applications/SpaceAnalyzer/ProgressWindow.cpp

@@ -16,7 +16,7 @@ ErrorOr<NonnullRefPtr<ProgressWindow>> ProgressWindow::try_create(StringView tit
 
     auto main_widget = TRY(window->set_main_widget<GUI::Widget>());
     main_widget->set_fill_with_background_color(true);
-    (void)TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>());
+    TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>());
 
     auto label = TRY(main_widget->try_add<GUI::Label>("Analyzing storage space..."));
     label->set_fixed_height(22);

Userland/Applications/Terminal/main.cpp

@@ -175,10 +175,10 @@ static ErrorOr<NonnullRefPtr<GUI::Window>> create_find_window(VT::TerminalWidget
     auto main_widget = TRY(window->set_main_widget<GUI::Widget>());
     main_widget->set_fill_with_background_color(true);
     main_widget->set_background_role(ColorRole::Button);
-    (void)TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>(4));
+    TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>(4));
 
     auto find = TRY(main_widget->try_add<GUI::Widget>());
-    (void)TRY(find->try_set_layout<GUI::HorizontalBoxLayout>(4));
+    TRY(find->try_set_layout<GUI::HorizontalBoxLayout>(4));
     find->set_fixed_height(30);
 
     auto find_textbox = TRY(find->try_add<GUI::TextBox>());

Userland/Applications/ThemeEditor/MainWidget.cpp

@@ -435,12 +435,12 @@ ErrorOr<void> MainWidget::add_property_tab(PropertyTab const& property_tab)
 
     auto properties_list = TRY(GUI::Widget::try_create());
     scrollable_container->set_widget(properties_list);
-    (void)TRY(properties_list->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 8 }, 12));
+    TRY(properties_list->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 8 }, 12));
 
     for (auto const& group : property_tab.property_groups) {
         NonnullRefPtr<GUI::GroupBox> group_box = TRY(properties_list->try_add<GUI::GroupBox>(group.title));
         // 1px less on the left makes the text line up with the group title.
-        (void)TRY(group_box->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 8, 8, 8, 7 }, 12));
+        TRY(group_box->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 8, 8, 8, 7 }, 12));
         group_box->set_preferred_height(GUI::SpecialDimension::Fit);
 
         for (auto const& property : group.properties) {

Userland/Demos/CatDog/main.cpp

@@ -42,7 +42,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
 
     auto catdog_widget = TRY(CatDog::create());
     window->set_main_widget(catdog_widget);
-    (void)TRY(catdog_widget->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins {}, 0));
+    TRY(catdog_widget->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins {}, 0));
 
     auto context_menu = TRY(GUI::Menu::try_create());
     TRY(context_menu->try_add_action(GUI::CommonActions::make_about_action("CatDog Demo", app_icon, window)));
@@ -62,7 +62,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     advice_window->set_alpha_hit_threshold(1.0f);
 
     auto advice_widget = TRY(advice_window->set_main_widget<SpeechBubble>(catdog_widget));
-    (void)TRY(advice_widget->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins {}, 0));
+    TRY(advice_widget->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins {}, 0));
 
     auto advice_timer = TRY(Core::Timer::create_single_shot(15'000, [&] {
         window->move_to_front();

Userland/Demos/ModelGallery/GalleryWidget.cpp

@@ -13,7 +13,7 @@ GalleryWidget::GalleryWidget()
     set_layout<GUI::VerticalBoxLayout>();
 
     auto& inner_widget = add<GUI::Widget>();
-    (void)inner_widget.try_set_layout<GUI::VerticalBoxLayout>(4).release_value_but_fixme_should_propagate_errors();
+    inner_widget.try_set_layout<GUI::VerticalBoxLayout>(4).release_value_but_fixme_should_propagate_errors();
 
     m_tab_widget = inner_widget.try_add<GUI::TabWidget>().release_value_but_fixme_should_propagate_errors();
     m_statusbar = add<GUI::Statusbar>();

Userland/DevTools/Profiler/main.cpp

@@ -132,7 +132,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     auto tab_widget = TRY(main_splitter->try_add<GUI::TabWidget>());
 
     auto tree_tab = TRY(tab_widget->try_add_tab<GUI::Widget>("Call Tree"));
-    (void)TRY(tree_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
+    TRY(tree_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
     auto bottom_splitter = TRY(tree_tab->try_add<GUI::VerticalSplitter>());
 
     auto tree_view = TRY(bottom_splitter->try_add<GUI::TreeView>());
@@ -181,7 +181,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     });
 
     auto samples_tab = TRY(tab_widget->try_add_tab<GUI::Widget>("Samples"));
-    (void)TRY(samples_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
+    TRY(samples_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
 
     auto samples_splitter = TRY(samples_tab->try_add<GUI::HorizontalSplitter>());
     auto samples_table_view = TRY(samples_splitter->try_add<GUI::TableView>());
@@ -195,7 +195,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     };
 
     auto signposts_tab = TRY(tab_widget->try_add_tab<GUI::Widget>("Signposts"));
-    (void)TRY(signposts_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
+    TRY(signposts_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
 
     auto signposts_splitter = TRY(signposts_tab->try_add<GUI::HorizontalSplitter>());
     auto signposts_table_view = TRY(signposts_splitter->try_add<GUI::TableView>());
@@ -209,7 +209,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     };
 
     auto flamegraph_tab = TRY(tab_widget->try_add_tab<GUI::Widget>("Flame Graph"));
-    (void)TRY(flamegraph_tab->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 4, 4, 4 }));
+    TRY(flamegraph_tab->try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins { 4, 4, 4, 4 }));
 
     auto flamegraph_view = TRY(flamegraph_tab->try_add<FlameGraphView>(profile->model(), ProfileModel::Column::StackFrame, ProfileModel::Column::SampleCount));
 
@@ -257,7 +257,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     flamegraph_view->on_hover_change = [&] { statusbar_update(); };
 
     auto filesystem_events_tab = TRY(tab_widget->try_add_tab<GUI::Widget>("Filesystem events"));
-    (void)TRY(filesystem_events_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
+    TRY(filesystem_events_tab->try_set_layout<GUI::VerticalBoxLayout>(4));
 
     auto filesystem_events_tree_view = TRY(filesystem_events_tab->try_add<GUI::TreeView>());
     filesystem_events_tree_view->set_should_fill_selected_rows(true);

Userland/Games/GameOfLife/main.cpp

@@ -60,7 +60,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     main_toolbar.layout()->set_margins({ 0, 6 });
 
     auto& board_widget_container = *main_widget->find_descendant_of_type_named<GUI::Widget>("board_widget_container");
-    (void)TRY(board_widget_container.try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins {}, 0));
+    TRY(board_widget_container.try_set_layout<GUI::VerticalBoxLayout>(GUI::Margins {}, 0));
     auto board_widget = TRY(board_widget_container.try_add<BoardWidget>(board_rows, board_columns));
     board_widget->randomize_cells();
 

Userland/Libraries/LibGUI/SettingsWindow.cpp

@@ -34,13 +34,13 @@ ErrorOr<NonnullRefPtr<SettingsWindow>> SettingsWindow::create(DeprecatedString t
 
     auto main_widget = TRY(window->set_main_widget<GUI::Widget>());
     main_widget->set_fill_with_background_color(true);
-    (void)TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>(4, 6));
+    TRY(main_widget->try_set_layout<GUI::VerticalBoxLayout>(4, 6));
 
     window->m_tab_widget = TRY(main_widget->try_add<GUI::TabWidget>());
 
     auto button_container = TRY(main_widget->try_add<GUI::Widget>());
     button_container->set_preferred_size({ SpecialDimension::Grow, SpecialDimension::Fit });
-    (void)TRY(button_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins {}, 6));
+    TRY(button_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins {}, 6));
 
     if (show_defaults_button == ShowDefaultsButton::Yes) {
         window->m_reset_button = TRY(button_container->try_add<GUI::DialogButton>(TRY(String::from_utf8("Defaults"sv))));

Userland/Libraries/LibGUI/Widget.h

@@ -83,19 +83,18 @@ public:
     void set_layout(NonnullRefPtr<Layout>);
 
     template<class T, class... Args>
-    ErrorOr<NonnullRefPtr<T>> try_set_layout(Args&&... args)
+    ErrorOr<void> try_set_layout(Args&&... args)
     {
         auto layout = TRY(T::try_create(forward<Args>(args)...));
         set_layout(*layout);
-        return layout;
+        return {};
     }
 
     template<class T, class... Args>
-    inline T& set_layout(Args&&... args)
+    inline void set_layout(Args&&... args)
     {
         auto layout = T::construct(forward<Args>(args)...);
         set_layout(*layout);
-        return layout;
     }
 
     UISize min_size() const { return m_min_size; }

Userland/Services/Taskbar/TaskbarWindow.cpp

@@ -73,13 +73,13 @@ TaskbarWindow::TaskbarWindow()
 ErrorOr<void> TaskbarWindow::populate_taskbar()
 {
     auto main_widget = TRY(set_main_widget<TaskbarWidget>());
-    (void)TRY(main_widget->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins { 2, 3, 0, 3 }));
+    TRY(main_widget->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins { 2, 3, 0, 3 }));
 
     m_quick_launch = TRY(Taskbar::QuickLaunchWidget::create());
     TRY(main_widget->try_add_child(*m_quick_launch));
 
     m_task_button_container = TRY(main_widget->try_add<GUI::Widget>());
-    (void)TRY(m_task_button_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins {}, 3));
+    TRY(m_task_button_container->try_set_layout<GUI::HorizontalBoxLayout>(GUI::Margins {}, 3));
 
     m_default_icon = TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/window.png"sv));