Refactored event loop.

This allows large numbers of events to be handled in bulk, but without
the program eating up CPU when idle.

src/main.rs

@@ -33,6 +33,9 @@ fn main() {
     // Get command-line arguments
     let args: Args = Docopt::new(USAGE).and_then(|d| d.decode()).unwrap_or_else(|e| e.exit());
     
+    // Quitting flag
+    let mut quit = false;
+    
     let mut width = rustbox::width();
     let mut height = rustbox::height();
     
@@ -40,11 +43,47 @@ fn main() {
     
     rustbox::init();
     
-    let enough_time_has_passed: bool = true;
-    
     loop {
+        // Handle events.  We block on the first event, so that the
+        // program doesn't loop like crazy, but then continue pulling
+        // events in a non-blocking way until we run out of events
+        // to handle.
+        let mut e = rustbox::poll_event(); // Block until we get an event
+        loop {
+            match e {
+                rustbox::Event::KeyEvent(modifier, key, character) => {
+                    // Return
+                    if key == 13 {
+                        let p = tb.len();
+                        tb.insert_text("\n", p);
+                    }
+                    // Esc
+                    else if key == 27 {
+                        quit = true;
+                        break;
+                    }
+                    // Some key
+                    else if let Option::Some(c) = char::from_u32(character) {
+                        let p = tb.len();
+                        tb.insert_text(c.to_string().as_slice(), p);
+                    }
+                },
+                
+                rustbox::Event::ResizeEvent(w, h) => {
+                    width = w as uint;
+                    height = h as uint;
+                }
+                
+                _ => {
+                    break;
+                }
+            }
+
+            e = rustbox::peek_event(0); // Get next event (if any)
+        }
+        
+        
         // Draw the text buffer to screen
-        if enough_time_has_passed {
         rustbox::clear();
         {
             let mut tb_iter = tb.root_iter();
@@ -77,34 +116,12 @@ fn main() {
             }
         }
         rustbox::present();
-        }
         
-        // Handle events
+        
-        match rustbox::poll_event() {
+        // Quit if quit flag is set
-            rustbox::Event::KeyEvent(modifier, key, character) => {
+        if quit {
-                // Return
-                if key == 13 {
-                    let p = tb.len();
-                    tb.insert_text("\n", p);
-                }
-                // Esc
-                else if key == 27 {
             break;
         }
-                // Some key
-                else if let Option::Some(c) = char::from_u32(character) {
-                    let p = tb.len();
-                    tb.insert_text(c.to_string().as_slice(), p);
-                }
-            },
-            
-            rustbox::Event::ResizeEvent(w, h) => {
-                width = w as uint;
-                height = h as uint;
-            }
-            
-            _ => {break;}
-        }
     }
     
     rustbox::shutdown();