Activity for testcase_list

rustbyexample/hello/print_display2.rs

@@ -21,6 +21,18 @@ impl fmt::Display for Point2D {
     }
 }
 
+#[derive(Debug)]
+struct Complex {
+    real: f64,
+    imag: f64,
+}
+
+impl fmt::Display for Complex {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{} + {}i", self.real, self.imag)
+    }
+}
+
 fn main() {
     let minmax = MinMax(0, 14);
 
@@ -42,4 +54,13 @@ fn main() {
     println!("Compare points:");
     println!("Display: {}", point);
     println!("Debug: {:?}", point);
+
+    let cmplx = Complex {
+        real: 3.3,
+        imag: 7.2,
+    };
+
+    println!("Compare complexes:");
+    println!("Display: {}", cmplx);
+    println!("Debug: {:?}", cmplx);
 }

rustbyexample/hello/testcase_list.rs

@@ -0,0 +1,25 @@
+use std::fmt;
+
+struct List(Vec<i32>);
+
+impl fmt::Display for List {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let vec = &self.0;
+
+        write!(f, "[")?;
+
+        for (count, v) in vec.iter().enumerate() {
+            if count != 0 {
+                write!(f, ", ")?;
+            }
+            write!(f, "{}: {}", count, v)?;
+        }
+
+        write!(f, "]")
+    }
+}
+
+fn main() {
+    let v = List(vec![1, 2, 3]);
+    println!("{}", v);
+}