Give unimplemented errors for other platforms.

src/lib.rs

@@ -218,6 +218,8 @@ pub mod window {
     }
 
     /// Get the position of the window.
+    /// TODO: implement for other platforms
+    #[cfg(target_os = "windows")]
     pub fn get_window_position() -> (u32, u32) {
         let mut d = native_display().lock().unwrap();
         d.screen_position

src/native/linux_x11.rs

@@ -324,6 +324,9 @@ impl X11Display {
                     new_width,
                     new_height,
                 } => self.set_window_size(self.window, new_width as _, new_height as _),
+                SetWindowPosition { new_x, new_y } => {
+                    eprintln!("Not implemented for X11")
+                }
                 SetFullscreen(fullscreen) => self.set_fullscreen(self.window, fullscreen),
                 ShowKeyboard(show) => {
                     eprintln!("Not implemented for X11")

src/native/macos.rs

@@ -183,6 +183,9 @@ impl MacosDisplay {
                     new_height,
                 } => self.set_window_size(new_width as _, new_height as _),
                 SetFullscreen(fullscreen) => self.set_fullscreen(fullscreen),
+                SetWindowPosition{new_x, new_y} => {
+                    eprintln!("Not implemented for macos");
+                }
                 _ => {}
             }
         }