rectangles: add can_hold function

rectangles/src/main.rs

@@ -8,6 +8,10 @@ impl Rectangle {
     fn area(&self) -> u32 {
         self.width * self.height
     }
+
+    fn can_hold(&self, other: &Rectangle) -> bool {
+        self.width > other.width && self.height > other.height
+    }
 }
 
 fn main() {
@@ -40,6 +44,12 @@ fn main() {
         "The area of the rectangle is {} square pixels.",
         rect.area()
     );
+
+    println!(
+        "The rectangle {:#?} can hold itself obviously: {}.",
+        rect,
+	rect.can_hold(&rect),
+    );
 }
 
 fn area(width: u32, height: u32) -> u32 {