Add Smart Pointers

book/smart_pointers/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "smart_pointers"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

book/smart_pointers/src/main.rs

@@ -0,0 +1,33 @@
+use std::ops::Deref;
+
+struct MyBox<T>(T);
+
+impl<T> MyBox<T> {
+    fn new(x: T) -> MyBox<T> {
+        MyBox(x)
+    }
+}
+
+impl<T> Deref for MyBox<T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+fn hello(name: &str) {
+    println!("Hello, {}!", name);
+}
+
+fn main() {
+    let x = 5;
+    let y = MyBox::new(x);
+
+    assert_eq!(5, x);
+    assert_eq!(5, *y);
+
+    let m = MyBox::new("Rust");
+    hello(&m);
+    get_name();
+}