added more examples from lectures

Author: BartMassey

README.md

@@ -51,3 +51,8 @@ in a controlled repository now.
 * `nullptr.rs`: null pointer example
 * `c++-ffi/`: example of FFI between C, C++ and Rust
 * `ownership-demo/`: example of ownership and borrowing stuff in C and Rust
+* `rust-winter2022/`: examples from Rust class Winter 2022
+* `struct-example.rs`: example of Rust struct
+* `enum-example.rs`: example of Rust enum
+* `closure-example.rs`: example of Rust closure
+* `iterator-example.rs`: example of Rust iterator

closure-example.rs

@@ -0,0 +1,7 @@
+fn sum_off(c: u32) -> u32 {
+    (1u32..=3).map(|n| { n * n + c }).sum::<u32>()
+}
+
+fn main() {
+    println!("{}", sum_off(7));
+}

enum-example.rs

@@ -0,0 +1,19 @@
+#[derive(Debug, Clone, Copy)]
+enum Color {
+    Red,
+    Green,
+    Blue,
+    Custom(u8, u8, u8),
+}
+use Color::*;
+
+fn main() {
+    let color = Custom(127,127,0);
+    let color_name = match color {
+        Red => "#ff0000".to_string(),
+        Green => "#00ff00".to_string(),
+        Blue => "#0000ff".to_string(),
+        Custom(r, g, b) => format!("#{:02x}{:02x}{:02x}", r, g, b),
+    };
+    println!("{}", color_name);
+}

generics-example.rs

@@ -0,0 +1,34 @@
+#[derive(Debug, Clone)]
+struct P<T>(T, T);
+
+impl<T> P<T> {
+    fn first(&self) -> T
+        where T: Clone
+    {
+        self.0.clone()
+    }
+
+    fn sum(&self) -> T
+        where T: std::ops::Add<Output = T>, T: Clone
+    {
+        self.0.clone() + self.1.clone()
+    }
+
+    fn pair(&self) -> (Self, Self)
+        where Self: Clone
+    {
+        (self.clone(), self.clone())
+    }
+}
+
+#[derive(Debug, Clone)]
+struct Eg;
+
+fn main() {
+    let p = P(1u32, 2);
+    println!("{}", p.sum());
+    let p = P("hello", "world");
+    println!("{}", p.first());
+    let p = P(Eg, Eg);
+    println!("{:?}", p.pair());
+}

rust-winter2022/class-2022-01-05.rs

@@ -0,0 +1,7 @@
+fn main() {
+    let v: Vec<u8> = vec![1, 2];
+    let mut it = v.into_iter().rev();
+    while let Some(val) = it.next() {
+        println!("{}", val);
+    }
+}

struct-example.rs

@@ -0,0 +1,16 @@
+#[derive(Debug, Clone)]
+struct Point2D(i64, i64);
+
+impl Point2D {
+    fn offset_point2d(&mut self, (x_off, y_off): (i64, i64)) {
+        self.0 += x_off;
+        self.1 += y_off;
+    }
+}
+
+fn main() {
+    let origin = Point2D(0, 0);
+    let mut my_point = origin.clone();
+    my_point.offset_point2d((1, 1));
+    println!("origin = {:?}; mypoint = {:?}", origin, my_point);
+}