Flatten the namespaces.

Remove:
* ftxui::screen
* ftxui::dom
* ftxui::component

Keep:
* ftxui

ftxui/src/ftxui/component/component.cpp

@@ -2,7 +2,7 @@
 #include "ftxui/component/delegate.hpp"
 #include <assert.h>
 
-namespace ftxui::component {
+namespace ftxui {
 
 Component::Component(Delegate* delegate) {
   delegate_ = delegate;
@@ -11,8 +11,8 @@ Component::Component(Delegate* delegate) {
 
 Component::~Component() {}
 
-dom::Element Component::Render() {
-  using namespace ftxui::dom;
+Element Component::Render() {
+  using namespace ftxui;
   return text(L"Not implemented component");
 }
 
@@ -54,4 +54,4 @@ Component* Component::Parent() {
   return parent_delegate->component();
 }
 
-}  // namespace ftxui::component
+}  // namespace ftxui

ftxui/src/ftxui/component/component_direction.cpp

@@ -1,6 +1,6 @@
 #include "ftxui/component/component_direction.hpp"
 
-namespace ftxui::component {
+namespace ftxui {
 
 ComponentDirection::ComponentDirection(Delegate* delegate)
     : Component(delegate), active_child_(nullptr) {}
@@ -16,6 +16,7 @@ bool ComponentDirection::OnEvent(Event event) {
     return true;
 
   return HandleDirection(event);
+
 }
 
 Component* ComponentDirection::GetActiveChild() {

ftxui/src/ftxui/component/component_horizontal.cpp

@@ -1,6 +1,6 @@
 #include "ftxui/component/component_horizontal.hpp"
 
-namespace ftxui::component {
+namespace ftxui {
 
 ComponentHorizontal::ComponentHorizontal(Delegate* delegate)
     : ComponentDirection(delegate) {}
@@ -27,4 +27,4 @@ bool ComponentHorizontal::HandleDirection(Event event) {
   return false;
 }
 
-}  // namespace ftxui::component
+}  // namespace ftxui

ftxui/src/ftxui/component/component_vertical.cpp

@@ -1,6 +1,6 @@
 #include "ftxui/component/component_vertical.hpp"
 
-namespace ftxui::component {
+namespace ftxui {
 
 ComponentVertical::ComponentVertical(Delegate* delegate)
     : ComponentDirection(delegate) {}
@@ -27,4 +27,4 @@ bool ComponentVertical::HandleDirection(Event event) {
   return false;
 }
 
-}  // namespace ftxui::component
+}  // namespace ftxui

ftxui/src/ftxui/component/event.cpp

@@ -1,6 +1,6 @@
 #include "ftxui/component/event.hpp"
 
-namespace ftxui::component {
+namespace ftxui {
 
 constexpr int ESC = int(27);
 
@@ -34,4 +34,4 @@ Event Event::F10{ESC, '[', '2', '1', '~'};
 Event Event::F11{ESC, '[', '2', '1', '~'};  // Same as F10 ?
 Event Event::F12{ESC, '[', '2', '4', '~'};
 
-} // namespace ftxui::component
+} // namespace ftxui

ftxui/src/ftxui/component/input.cpp

@@ -1,14 +1,13 @@
 #include "ftxui/component/input.hpp"
 #include "ftxui/util/string.hpp"
 
-namespace ftxui::component {
+namespace ftxui {
 
 Input::Input(Delegate* delegate): Component(delegate) {}
 Input::~Input() {}
 
 // Component implementation.
-dom::Element Input::Render() {
-  using namespace dom;
+Element Input::Render() {
   bool is_focused = Focused();
 
   // Placeholder.
@@ -75,4 +74,4 @@ bool Input::OnEvent(Event event) {
   return false;
 }
 
-}  // namespace ftxui::component
+}  // namespace ftxui

ftxui/src/ftxui/component/menu.cpp

@@ -2,12 +2,11 @@
 #include <algorithm>
 #include <iostream>
 
-namespace ftxui::component {
+namespace ftxui {
 
 Menu::Menu(Delegate* delegate) : Component(delegate) {}
 
-dom::Element Menu::Render() {
-  using namespace dom;
+Element Menu::Render() {
   std::vector<Element> elements;
   bool focused = Focused();
   for (size_t i = 0; i < entries.size(); ++i) {
@@ -49,4 +48,4 @@ bool Menu::OnEvent(Event event) {
   return false;
 }
 
-}  // namespace ftxui::component
+}  // namespace ftxui

ftxui/src/ftxui/component/screen_interactive.cpp

@@ -6,9 +6,9 @@
 #include <iostream>
 #include "ftxui/component/component.hpp"
 #include "ftxui/component/delegate.hpp"
-#include "ftxui/terminal.hpp"
+#include "ftxui/screen/terminal.hpp"
 
-namespace ftxui::component {
+namespace ftxui {
 
 namespace {
 constexpr int ESC = 27;
@@ -42,13 +42,14 @@ Event GetEvent() {
 
   return Event{v1};
 };
+
 };  // namespace
 
-class ScreenInteractive::Delegate : public component::Delegate {
+class ScreenInteractive::Delegate : public Component::Delegate {
  public:
   Delegate() : root_(this) {}
 
-  void Register(component::Component* c) override { component_ = c; }
+  void Register(Component* c) override { component_ = c; }
 
   std::vector<std::unique_ptr<Delegate>> child_;
   Delegate* NewChild() override {
@@ -67,24 +68,24 @@ class ScreenInteractive::Delegate : public component::Delegate {
 
   void OnEvent(Event event) { component_->OnEvent(event); }
 
-  std::vector<component::Delegate*> children() override {
-    std::vector<component::Delegate*> ret;
+  std::vector<Component::Delegate*> children() override {
+    std::vector<Component::Delegate*> ret;
     for (auto& it : child_)
       ret.push_back(it.get());
     return ret;
   }
 
-  Delegate* root_;
-  Delegate* parent_ = nullptr;
-  Delegate* previous_sibling_ = nullptr;
-  Delegate* next_sibling_ = nullptr;
-  component::Component* component_;
+  Component::Delegate* root_;
+  Component::Delegate* parent_ = nullptr;
+  Component::Delegate* previous_sibling_ = nullptr;
+  Component::Delegate* next_sibling_ = nullptr;
+  Component* component_;
 
-  Delegate* Root() override { return root_; }
-  Delegate* Parent() override { return parent_; }
-  Delegate* PreviousSibling() override { return previous_sibling_; }
-  Delegate* NextSibling() override { return next_sibling_; }
-  component::Component* component() override { return component_; }
+  Component::Delegate* Root() override { return root_; }
+  Component::Delegate* Parent() override { return parent_; }
+  Component::Delegate* PreviousSibling() override { return previous_sibling_; }
+  Component::Delegate* NextSibling() override { return next_sibling_; }
+  Component* component() override { return component_; }
 };
 
 ScreenInteractive::ScreenInteractive(size_t dimx,
@@ -162,14 +163,14 @@ void ScreenInteractive::PrepareDraw() {
   if (dimx != dimx_ || dimy != dimy_) {
     dimx_ = dimx;
     dimy_ = dimy;
-    pixels_ = std::vector<std::vector<screen::Pixel>>(
-        dimy, std::vector<screen::Pixel>(dimx));
+    pixels_ = std::vector<std::vector<Pixel>>(
+        dimy, std::vector<Pixel>(dimx));
   }
 
   Render(*this, document.get());
 }
 
-component::Delegate* ScreenInteractive::delegate() {
+Component::Delegate* ScreenInteractive::delegate() {
   return delegate_.get();
 }
 
@@ -177,4 +178,4 @@ std::function<void()> ScreenInteractive::ExitLoopClosure() {
   return [this]() { quit_ = true; };
 }
 
-}  // namespace ftxui::component.
+}  // namespace ftxui.

ftxui/src/ftxui/component/toggle.cpp

@@ -1,11 +1,10 @@
 #include "ftxui/component/toggle.hpp"
 
-namespace ftxui::component {
+namespace ftxui {
 
 Toggle::Toggle(Delegate* delegate) : Component(delegate) {}
 
-dom::Element Toggle::Render() {
-  using namespace dom;
+Element Toggle::Render() {
   auto highlight = Focused() ? inverted : bold;
 
   Children children;
@@ -40,4 +39,4 @@ bool Toggle::OnEvent(Event event) {
   return false;
 }
 
-}  // namespace ftxui::component
+}  // namespace ftxui

ftxui/src/ftxui/dom/blink.cpp

@@ -1,14 +1,14 @@
 #include "ftxui/dom/node_decorator.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 class Blink : public NodeDecorator {
  public:
   Blink(Children children) : NodeDecorator(std::move(children)) {}
   ~Blink() override {}
 
-  void Render(screen::Screen& screen) override {
+  void Render(Screen& screen) override {
     Node::Render(screen);
     for (int y = box_.top; y <= box_.bottom; ++y) {
       for (int x = box_.left; x <= box_.right; ++x) {
@@ -22,4 +22,4 @@ std::unique_ptr<Node> blink(Child child) {
   return std::make_unique<Blink>(unpack(std::move(child)));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/bold.cpp

@@ -1,14 +1,14 @@
 #include "ftxui/dom/node_decorator.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 class Bold : public NodeDecorator {
  public:
   Bold(Children children) : NodeDecorator(std::move(children)) {}
   ~Bold() override {}
 
-  void Render(screen::Screen& screen) override {
+  void Render(Screen& screen) override {
     for (int y = box_.top; y <= box_.bottom; ++y) {
       for (int x = box_.left; x <= box_.right; ++x) {
         screen.PixelAt(x,y).bold = true; 
@@ -22,4 +22,4 @@ std::unique_ptr<Node> bold(Child child) {
   return std::make_unique<Bold>(unpack(std::move(child)));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/color.cpp

@@ -1,14 +1,14 @@
 #include "ftxui/dom/node_decorator.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 class BgColor : public NodeDecorator {
  public:
   BgColor(Children children, Color color)
       : NodeDecorator(std::move(children)), color_(color) {}
 
-  void Render(screen::Screen& screen) override {
+  void Render(Screen& screen) override {
     for (int y = box_.top; y <= box_.bottom; ++y) {
       for (int x = box_.left; x <= box_.right; ++x) {
         screen.PixelAt(x, y).background_color = color_;
@@ -26,7 +26,7 @@ class FgColor : public NodeDecorator {
       : NodeDecorator(std::move(children)), color_(color) {}
   ~FgColor() override {}
 
-  void Render(screen::Screen& screen) override {
+  void Render(Screen& screen) override {
     for (int y = box_.top; y <= box_.bottom; ++y) {
       for (int x = box_.left; x <= box_.right; ++x) {
         screen.PixelAt(x, y).foreground_color = color_;
@@ -58,4 +58,4 @@ Decorator bgcolor(Color c) {
   };
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/composite_decorator.cpp

@@ -1,7 +1,7 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 std::unique_ptr<Node> hcenter(Element child) {
   return hbox(filler(), std::move(child), filler());
@@ -19,4 +19,4 @@ std::unique_ptr<Node> align_right(Element child) {
   return hbox(filler(), std::move(child));
 }
 
-} // namespace ftxui::dom
+} // namespace ftxui

ftxui/src/ftxui/dom/dbox.cpp

@@ -1,7 +1,7 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 class DBox : public Node {
  public:
@@ -32,4 +32,4 @@ std::unique_ptr<Node> dbox(Children children) {
   return std::make_unique<DBox>(std::move(children));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/dim.cpp

@@ -1,9 +1,9 @@
 #include "ftxui/dom/node_decorator.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using ftxui::screen::Screen;
+using ftxui::Screen;
 
 class Dim : public NodeDecorator {
  public:
@@ -24,4 +24,4 @@ std::unique_ptr<Node> dim(Child child) {
   return std::make_unique<Dim>(unpack(std::move(child)));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/flex.cpp

@@ -1,7 +1,7 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 class Flex : public Node {
  public:
@@ -34,4 +34,4 @@ std::unique_ptr<Node> flex(Element child) {
   return std::make_unique<Flex>(std::move(child));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/frame.cpp

@@ -1,9 +1,9 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using namespace ftxui::screen;
+using namespace ftxui;
 
 static wchar_t charset[] = L"┌┐└┘─│┬┴┤├";
 
@@ -95,4 +95,4 @@ Decorator boxed() {
   };
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/gauge.cpp

@@ -1,9 +1,9 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using namespace ftxui::screen;
+using namespace ftxui;
 
 static wchar_t charset[] = L"  ▏▎▍▌▋▊▉█";
 
@@ -36,4 +36,4 @@ std::unique_ptr<Node> gauge(float progress) {
   return std::make_unique<Gauge>(progress);
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/gauge_test.cpp

@@ -2,8 +2,8 @@
 #include "ftxui/screen/screen.hpp"
 #include "gtest/gtest.h"
 
-using namespace ftxui::screen;
-using namespace ftxui::dom;
+using namespace ftxui;
+using namespace ftxui;
 
 TEST(GaugeTest, zero) {
   auto root = gauge(0);

ftxui/src/ftxui/dom/hbox.cpp

@@ -1,7 +1,7 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 class HBox : public Node {
  public:
@@ -63,4 +63,4 @@ std::unique_ptr<Node> hbox(Children children) {
   return std::make_unique<HBox>(std::move(children));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/hbox_test.cpp

@@ -2,8 +2,8 @@
 #include "ftxui/screen/screen.hpp"
 #include "gtest/gtest.h"
 
-using namespace ftxui::screen;
-using namespace ftxui::dom;
+using namespace ftxui;
+using namespace ftxui;
 
 TEST(HBoxTest, ScreenSmaller1) {
   auto root = hbox(

ftxui/src/ftxui/dom/inverted.cpp

@@ -1,9 +1,9 @@
 #include "ftxui/dom/node_decorator.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using ftxui::screen::Screen;
+using ftxui::Screen;
 
 class Inverted : public NodeDecorator {
  public:
@@ -24,4 +24,4 @@ std::unique_ptr<Node> inverted(Child child) {
   return std::make_unique<Inverted>(unpack(std::move(child)));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/node.cpp

@@ -1,8 +1,8 @@
 #include "ftxui/dom/node.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using ftxui::screen::Screen;
+using ftxui::Screen;
 
 Node::Node() {}
 Node::Node(std::vector<std::unique_ptr<Node>> children)
@@ -40,4 +40,4 @@ void Render(Screen& screen, Node* node) {
   node->Render(screen);
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/node_decorator.cpp

@@ -1,6 +1,6 @@
 #include "ftxui/dom/node_decorator.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 void NodeDecorator::ComputeRequirement() {
   Node::ComputeRequirement();
@@ -12,4 +12,4 @@ void NodeDecorator::SetBox(Box box) {
   children[0]->SetBox(box);
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/node_decorator.hpp

@@ -4,7 +4,7 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 // Helper class.
 class NodeDecorator : public Node {
@@ -15,6 +15,6 @@ class NodeDecorator : public Node {
   void SetBox(Box box) override;
 };
 
-};  // namespace ftxui::dom
+};  // namespace ftxui
 
 #endif /* end of include guard: FTXUI_DOM_NODE_DECORATOR_H_ */

ftxui/src/ftxui/dom/separator.cpp

@@ -1,8 +1,8 @@
 #include "ftxui/dom/node.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using ftxui::screen::Screen;
+using ftxui::Screen;
 
 class Separator : public Node {
  public:
@@ -35,4 +35,4 @@ std::unique_ptr<Node> separator() {
   return std::make_unique<Separator>();
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/size.cpp

@@ -1,7 +1,7 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 class Size : public Node {
  public:
@@ -32,4 +32,4 @@ Decorator size(size_t width, size_t height) {
   };
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/spinner.cpp

@@ -1,9 +1,9 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using namespace ftxui::screen;
+using namespace ftxui;
 
 static const std::vector<std::vector<std::vector<std::wstring>>> elements = {
   {
@@ -276,4 +276,4 @@ std::unique_ptr<Node> spinner(int c, size_t index) {
   return vbox(std::move(lines));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/text.cpp

@@ -1,8 +1,8 @@
 #include "ftxui/dom/node.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using ftxui::screen::Screen;
+using ftxui::Screen;
 
 class Text : public Node {
  public:
@@ -34,4 +34,4 @@ std::unique_ptr<Node> text(std::wstring text) {
   return std::make_unique<Text>(text);
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/text_test.cpp

@@ -2,8 +2,8 @@
 #include "ftxui/screen/screen.hpp"
 #include "gtest/gtest.h"
 
-using namespace ftxui::screen;
-using namespace ftxui::dom;
+using namespace ftxui;
+using namespace ftxui;
 
 TEST(TextTest, ScreenHeightSmaller) {
   auto element = text(L"test");

ftxui/src/ftxui/dom/underlined.cpp

@@ -1,9 +1,9 @@
 #include "ftxui/dom/node_decorator.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
-using ftxui::screen::Screen;
+using ftxui::Screen;
 
 class Underlined : public NodeDecorator {
  public:
@@ -24,4 +24,4 @@ std::unique_ptr<Node> underlined(Child child) {
   return std::make_unique<Underlined>(unpack(std::move(child)));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/util.cpp

@@ -1,6 +1,6 @@
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 Element nothing(Element element) {
   return std::move(element);
@@ -23,4 +23,4 @@ Element operator|(Element e, Decorator d) {
   return d(std::move(e));
 }
 
-}  // namespace ftxui::dom
+}  // namespace ftxui

ftxui/src/ftxui/dom/vbox.cpp

@@ -1,7 +1,7 @@
 #include "ftxui/dom/node.hpp"
 #include "ftxui/dom/elements.hpp"
 
-namespace ftxui::dom {
+namespace ftxui {
 
 class VBox : public Node {
  public:
@@ -63,4 +63,4 @@ std::unique_ptr<Node> vbox(Children children) {
   return std::make_unique<VBox>(std::move(children));
 }
 
-};  // namespace ftxui::dom
+};  // namespace ftxui

ftxui/src/ftxui/dom/vbox_test.cpp

@@ -2,8 +2,8 @@
 #include "ftxui/screen/screen.hpp"
 #include "gtest/gtest.h"
 
-using namespace ftxui::screen;
-using namespace ftxui::dom;
+using namespace ftxui;
+using namespace ftxui;
 
 TEST(VBoxTest, ScreenSmaller1) {
   auto root = vbox(text(L"text_1"), text(L"text_2"));

ftxui/src/ftxui/screen/screen.cpp

@@ -1,11 +1,11 @@
-#include "ftxui/screen/screen.hpp"
 #include "ftxui/dom/node.hpp"
-#include "ftxui/terminal.hpp"
-#include "ftxui/util/string.hpp"
+#include "ftxui/screen/screen.hpp"
+#include "ftxui/screen/string.hpp"
+#include "ftxui/screen/terminal.hpp"
 
 #include <sstream>
 
-namespace ftxui::screen {
+namespace ftxui {
 
 static const wchar_t* BOLD_SET = L"\e[1m";
 static const wchar_t* BOLD_RESET = L"\e[22m"; // Can't use 21 here.
@@ -86,7 +86,7 @@ Screen Screen::TerminalFullscreen() {
 }
 
 // static
-Screen Screen::TerminalOutput(std::unique_ptr<dom::Node>& element) {
+Screen Screen::TerminalOutput(std::unique_ptr<Node>& element) {
   element->ComputeRequirement();
   Terminal::Dimensions size = Terminal::Size();
   return Screen(size.dimx, element->requirement().min.y);
@@ -106,4 +106,4 @@ void Screen::Clear() {
                                             std::vector<Pixel>(dimx_, Pixel()));
 }
 
-};  // namespace ftxui::screen
+};  // namespace ftxui

ftxui/src/ftxui/screen/terminal.cpp

@@ -2,7 +2,7 @@
 #include <stdio.h>
 #include <unistd.h>
 
-#include "ftxui/terminal.hpp"
+#include "ftxui/screen/terminal.hpp"
 
 namespace ftxui {