Add exit code example

examples/exit_code.rs

@@ -0,0 +1,57 @@
+use {
+    simple_logger::SimpleLogger,
+    winit::{
+        event::{Event, KeyboardInput, VirtualKeyCode, WindowEvent},
+        event_loop::{ControlFlow, EventLoop},
+        window::WindowBuilder,
+    },
+};
+
+fn main() {
+    SimpleLogger::new().init().unwrap();
+    let event_loop = EventLoop::new();
+
+    let _window = WindowBuilder::new()
+        .with_title("Highly unstable window")
+        .build(&event_loop)
+        .unwrap();
+
+    println!("Use your number keys (0-9) to enter an exit code!");
+
+    event_loop.run(move |event, _, flow| {
+        *flow = ControlFlow::Wait;
+
+        match event {
+            Event::WindowEvent {
+                event:
+                    WindowEvent::KeyboardInput {
+                        input:
+                            KeyboardInput {
+                                virtual_keycode: Some(keycode),
+                                ..
+                            },
+                        ..
+                    },
+                ..
+            } => match keycode {
+                // actually perfect for a macro, but for simplicity I'll just refrain from that
+                VirtualKeyCode::Key1 => *flow = ControlFlow::Exit(1),
+                VirtualKeyCode::Key2 => *flow = ControlFlow::Exit(2),
+                VirtualKeyCode::Key3 => *flow = ControlFlow::Exit(3),
+                VirtualKeyCode::Key4 => *flow = ControlFlow::Exit(4),
+                VirtualKeyCode::Key5 => *flow = ControlFlow::Exit(5),
+                VirtualKeyCode::Key6 => *flow = ControlFlow::Exit(6),
+                VirtualKeyCode::Key7 => *flow = ControlFlow::Exit(7),
+                VirtualKeyCode::Key8 => *flow = ControlFlow::Exit(8),
+                VirtualKeyCode::Key9 => *flow = ControlFlow::Exit(9),
+                VirtualKeyCode::Key0 => *flow = ControlFlow::Exit(0),
+                _ => (),
+            },
+            Event::WindowEvent {
+                event: WindowEvent::CloseRequested,
+                ..
+            } => *flow = ControlFlow::Exit(47),
+            _ => (),
+        }
+    });
+}