Associated func/constructor

rustbook/rectangles/src/main.rs

@@ -12,17 +12,22 @@ impl Rectangle {
     fn can_hold(&self, other: &Rectangle) -> bool {
         self.width > other.width && self.height > other.height
     }
+
+    fn square(size: u32) -> Rectangle {
+        Rectangle { width: size, height: size }
+    }
 }
 
 fn main() {
     let rect1 = Rectangle { width: 30, height: 50 };
     let rect2 = Rectangle { width: 10, height: 40 };
     let rect3 = Rectangle { width: 60, height: 45 };
+    let rect4 = Rectangle::square(3);
 
     println!("Can rect1 hold rect2? {}", rect1.can_hold(&rect2));
     println!("Can rect1 hold rect3? {}", rect1.can_hold(&rect3));
 
-    for (i, rect) in [rect1, rect2, rect3].iter().enumerate() {
+    for (i, rect) in [rect1, rect2, rect3, rect4].iter().enumerate() {
         println!("rect{} has area {}", i+1, rect.area());
     }
 }