From f40981544c161b750e9890a1471e87b0582241a8 Mon Sep 17 00:00:00 2001
From: Dan Buch <dan@meatballhat.com>
Date: Sat, 11 Sep 2021 21:03:58 -0400
Subject: [PATCH] RBE custom types enum testcase linked list

---
 .../custom_types_enum_testcase_linked_list.rs | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)
 create mode 100644 rustbyexample/custom_types/custom_types_enum_testcase_linked_list.rs

diff --git a/rustbyexample/custom_types/custom_types_enum_testcase_linked_list.rs b/rustbyexample/custom_types/custom_types_enum_testcase_linked_list.rs
new file mode 100644
index 0000000..a6c8fcf
--- /dev/null
+++ b/rustbyexample/custom_types/custom_types_enum_testcase_linked_list.rs
@@ -0,0 +1,45 @@
+use crate::List::*;
+
+enum List {
+    Cons(u32, Box<List>),
+    Nil,
+}
+
+impl List {
+    fn new() -> List {
+        Nil
+    }
+
+    fn prepend(self, elem: u32) -> List {
+        Cons(elem, Box::new(self))
+    }
+
+    fn len(&self) -> u32 {
+        match *self {
+            Cons(_, ref tail) => 1 + tail.len(),
+            Nil => 0,
+        }
+    }
+
+    fn stringify(&self) -> String {
+        match *self {
+            Cons(head, ref tail) => {
+                format!("{}, {}", head, tail.stringify())
+            }
+            Nil => {
+                format!("Nil")
+            }
+        }
+    }
+}
+
+fn main() {
+    let mut list = List::new();
+
+    list = list.prepend(1);
+    list = list.prepend(2);
+    list = list.prepend(3);
+
+    println!("linked list has length: {}", list.len());
+    println!("{}", list.stringify());
+}