README.md

@@ -1 +0,0 @@
-simple implementation of linkedlist for rust workshop, with tags on every commit

src/main.rs

@@ -1,56 +1,34 @@
-fn main() {
-    let mut list = List::new();
-    list.push(1);
-    println!("push(1) : {:?}", list);
-    list.push(2);
-    println!("push(2) : {:?}", list);
-    println!("pop() -> {} : {:?}", list.pop().unwrap(), list);
-    println!("pop() -> {} : {:?}", list.pop().unwrap(), list);
+fn main() {}
+
+#[derive(Debug)]
+pub struct List {
+    head: Link,
 }
 
 #[derive(Debug)]
-pub struct List<T> {
-    head: Link<T>,
+enum Link {
+    Empty,
+    More(Box<Node>),
 }
 
-type Link<T> = Option<Box<Node<T>>>;
-
 #[derive(Debug)]
-struct Node<T> {
-    elem: T,
-    next: Link<T>,
+struct Node {
+    elem: i32,
+    next: Link,
 }
 
-impl<T> List<T> {
+impl List {
     pub fn new() -> Self {
-        Self { head: None }
+        Self { head: Link::Empty }
     }
 
-    pub fn push(&mut self, elem: T) {
+    pub fn push(&mut self, elem: i32) {
         let new_node = Node {
             elem: elem,
-            next: self.head.take(),
+            next: std::mem::replace(&mut self.head, Link::Empty),
         };
-        self.head = Some(Box::new(new_node));
-    }
-
-    pub fn pop(&mut self) -> Option<T> {
-        self.head.take().map(|node| {
-            self.head = node.next;
-            node.elem
-        })
+        self.head = Link::More(Box::new(new_node));
     }
 }
 
-#[cfg(test)]
-mod tests {
 
-    use super::*;
-
-    #[test]
-    fn test() {
-        let mut list = List::new();
-        list.push(42);
-        assert_eq!(Some(42), list.pop());
-    }
-}