Update 2024-01-28-lesson3.md

raikrahul · Jan 25, 2025 · ace1592 · ace1592
1 parent 0224c26
commit ace1592
Showing 1 changed file with 73 additions and 0 deletions.
diff --git a/_posts/2024-01-28-lesson3.md b/_posts/2024-01-28-lesson3.md
@@ -41,4 +41,77 @@ fn main() {
     };
 
     println!("User {} has email {}", user1.username, user1.email);
+}
+impl User {
+    // Associated function (constructor)
+    fn new(email: String, username: String) -> User {
+        User {
+            email,
+            username,
+            active: true,
+            sign_in_count: 0,
+        }
+    }
+
+    // Method (takes &self)
+    fn deactivate(&mut self) {
+        self.active = false;
+    }
+}
+
+fn main() {
+    let mut user2 = User::new(
+        String::from("admin@rust.org"),
+        String::from("admin")
+    );
+
+    user2.deactivate();
+    println!("Account active: {}", user2.active);
+}
+enum WebEvent {
+    PageLoad,
+    PageUnload,
+    KeyPress(char),
+    Paste(String),
+    Click { x: i64, y: i64 },
+}
+
+fn inspect(event: WebEvent) {
+    match event {
+        WebEvent::PageLoad => println!("page loaded"),
+        WebEvent::PageUnload => println!("page unloaded"),
+        WebEvent::KeyPress(c) => println!("pressed '{}'", c),
+        WebEvent::Paste(s) => println!("pasted \"{}\"", s),
+        WebEvent::Click { x, y } => {
+            println!("clicked at x={}, y={}", x, y);
+        }
+    }
+}
+
+fn main() {
+    let click = WebEvent::Click { x: 20, y: 80 };
+    inspect(click);
+}
+enum Shape {
+    Circle(f64),
+    Rectangle(f64, f64),
+    Triangle(f64, f64, f64),
+}
+
+struct Geometry {
+    shape: Shape,
+    color: String,
+}
+
+impl Geometry {
+    fn area(&self) -> f64 {
+        match self.shape {
+            Shape::Circle(radius) => 3.14159 * radius * radius,
+            Shape::Rectangle(w, h) => w * h,
+            Shape::Triangle(a, b, c) => {
+                let s = (a + b + c) / 2.0;
+                (s * (s - a) * (s - b) * (s - c)).sqrt()
+            }
+        }
+    }
 }