added linked_list from https://github.com/jlkiri/rust-data-structures/blob/master/src/linked_list.rs

src/data_structures.rs

@@ -232,3 +232,42 @@ impl<T> Stack<T> {
     self.stack.last()
   }
 }
+
+use std::mem;
+
+struct Node<T> {
+  value: T,
+  next: Option<Box<Node<T>>>,
+}
+
+type Link<T> = Option<Box<Node<T>>>;
+
+pub struct List<T> {
+  head: Link<T>,
+}
+
+impl<T> List<T> {
+  pub fn new() -> Self {
+    List { head: None }
+  }
+
+  pub fn push(&mut self, item: T) {
+    let next_node = Box::new(Node {
+      value: item,
+      next: self.head.take(),
+    });
+
+    self.head = Some(next_node)
+  }
+
+  pub fn pop(&mut self) -> Option<T> {
+    self.head.take().map(|node| {
+      self.head = node.next;
+      node.value
+    })
+  }
+
+  pub fn peek(&self) -> Option<&T> {
+    self.head.as_ref().map(|node| &node.value)
+  }
+}